BAA Handbook

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THE HANDBOOK

OF THE BRITISH ASTRONOMICAL ASSOCIATION 2020

2019 October ISSN 0068–130–X CONTENTS PREFACE ...... 2 HIGHLIGHTS FOR 2020 ...... 3 SKY DIARY ...... 4–5 CALENDAR 2020 ...... 6 SUN ...... 7–9 ECLIPSES ...... 10–17 APPEARANCE OF PLANETS ...... 18 VISIBILITY OF PLANETS ...... 19 RISING AND SETTING OF THE PLANETS IN LATITUDES 52°N AND 35°S ...... 20–21 PLANETS – Explanation of Tables ...... 22 ELEMENTS OF PLANETARY ORBITS ...... 23 MERCURY ...... 24–25 VENUS ...... 26 EARTH ...... 27 MOON ...... 27 LUNAR LIBRATION ...... 28 MOONRISE AND MOONSET ...... 30–33 SUN’S SELENOGRAPHIC COLONGITUDE ...... 34 LUNAR OCCULTATIONS ...... 35–41 GRAZING LUNAR OCCULTATIONS ...... 42–43 MARS ...... 44–45 ASTEROIDS ...... 46 ASTEROID EPHEMERIDES ...... 47–51 ASTEROID OCCULTATIONS ...... 52–55 ASTEROIDS: FAVOURABLE OBSERVING OPPORTUNITIES ...... 56–58 NEO CLOSE APPROACHES TO EARTH ...... 59 JUPITER ...... 60–64 SATELLITES OF JUPITER ...... 64–68 JUPITER ECLIPSES, OCCULTATIONS AND TRANSITS ...... 69–78 SATURN ...... 79–82 SATELLITES OF SATURN ...... 83–86 URANUS ...... 87 NEPTUNE ...... 88 TRANS–NEPTUNIAN & SCATTERED–DISK OBJECTS ...... 89 DWARF PLANETS ...... 90–93 COMETS ...... 94–98 METEOR DIARY ...... 99–101 VARIABLE STARS (RZ Cassiopeiae; Algol; RS Canum Venaticorum) ...... 102–103 MIRA STARS ...... 104 VARIABLE STAR OF THE YEAR (SV Sagittae) ...... 105–107 EPHEMERIDES OF VISUAL BINARY STARS ...... 108–109 BRIGHT STARS ...... 110 ACTIVE GALAXIES ...... 111 TIME ...... 112–113 ASTRONOMICAL AND PHYSICAL CONSTANTS ...... 114–115 GREEK ALPHABET ...... 115 ACKNOWLEDGMENTS / ERRATA ...... 116

Front Cover: Comet 46P/Wirtanen, taken 2018 December 8 by Martin Mobberley. Equipment – Televue NP127, FLI ProLine 16803 CCD British Astronomical Association

HANDBOOK FOR 2020

NINETY–NINTH YEAR OF PUBLICATION

Welcome to the 99th Handbook of the British Astronomical Association.

The Handbook highlights forthcoming astronomical events for the year, but there are always events that can be missed, or are entirely unpredictable, like comets, asteroid close approaches, aurorae, etc. Make sure you watch the BAA’s website for the latest news. Also, make sure you are receiving the new email newsletters by keeping your email up to date with the BAA office.

Once again we would also encourage everyone to join their local astronomical society to try equipment, talk to like–minded people, and to give and receive help. It can take a long time to choose the right equipment and learn how to use it, so make the most of your local society. The BAA’s Sections can help too. Contact the Section Directors, who will be pleased to help.

You may also like to consider getting involved with the annual events organised as part of World Space Week (Oct. 4–10). This is an international celebration of all things SPACE and focuses on science and technology and its role in the past, present and future of mankind. World Space Week currently consists of space education and outreach events held by space agencies, aerospace companies, schools, planetaria, museums, and astronomy clubs around the world. (http://www.worldspaceweek.org/).

Unfortunately we are restricted by the number of pages that we can include in the Handbook. This does mean that some things will have to be left out. This edition we have had to remove the Internet Resources pages to make room for more eclipse/transit pages. However, the Computing Section does publish all additional data on the section website (http://britastro.org/computing). This includes both Comet charts and Asteroid Oppositions and Appulses.

Members may also like to know that the Computing Section provides the data for the Royal Astronomical Society’s Diary.

Finally, we must thank all the contributors to the Handbook. You will find them acknowledged on page 116. Contact details for many of these can be found at the back of every Journal. Alternatively, email the Director, Steve Harvey (address below) and messages can be forwarded to those concerned.

Clear skies for 2020 ! Steve Harvey FRAS Director, Computing Section Email: [email protected]

2019 August 2 Preface BAA Handbook 2020 HIGHLIGHTS FOR 2020 The following events during 2020 are worthy of note: Sun and Moon: There will be six eclipses (two of the Sun and four of the Moon). All four lunar eclipses are quite observationally challenging penumbral eclipses. An annular solar eclipse occurs June 21 and a total solar eclipse shall be visble in South America, December 14.

Planets, Dwarf Planets and Asteroids: Mercury is best seen around the time of greatest elongation. For the mornings, this will be March 24, July 22 and November 10. Whilst for evening apparitions it will be February 10, June 04 and October 01. Venus is an evening object for the first half of the year and a morning object for the second half of the year. It is at Greatest Western Elongation of 46 degrees from the Sun on March 24 and again August 12. Mars is visible as an all–night object until October, after which it becomes a morning object again. Meteors: Among the meteor showers, the most favourable are: the Lyrids (April), Leonids (November) and the Geminids (December). Also favourable are: Quadrantids, Perseids, Kappa Cygnids, Orionids and the Ursids. Comets: Comet C/2017 T2 (PANSTARRS) is expected to reach peak brightness in May at +7, whilst 88P/ Howell is predicted to reach +8 in September. It is also worth paying attention to Comet 29P/Sch- wassmann–Wachmann, given that it outbursts several times each year. Refer to the BAA Comet Section for latest info : http://britastro.org/comet Space Probes and Artificial Satellites: NASA plans to launch the Mars 2020 rover, whilst ESA and Roscosmos intend to launch the ExoMars lander and rover. China is to begin construction of a large modular space station with the launch of the Tianhe Core Cabin Module. NASA will carry out the maiden launch of the Space Launch System and SpaceX will begin orbital testing of its fully reusable two–stage–to–orbit vehi- cle BFR. In early 2020 following the launch of the first 300+ satellites, the OneWeb constellation is expected to become operational, whilst SpaceX expects to begin operation of its Starlink system, with about 720 satellites launched by the end of the year. Positional predictions for the ISS and other bright satellites can be found for any geographic location at: http://www.heavens–above.com Highlights by date: Jan. 10 Penumbral lunar eclipse visible from Europe, Africa, Asia and Australia. Mar. 18 Jupiter, Mars and Moon conjunction 05:00UT 20 The vernal equinox occurs in the northern hemisphere at 03:50 UT Apr. 22 Lyrid meteor shower Jun. 5 Penumbral lunar eclipse visible from Europe, Africa, Asia and Australia 20 The summer solstice occurs in the northern hemisphere at 21:44 UT 21 An annular solar eclipse visible from central East Africa and southern Asia. Jul. 5 Penumbral lunar eclipse visible from the Americas and W. Europe and Africa. 14 Jupiter at opposition 15 Pluto at opposition 20 Saturn at opposition Aug. 12 Perseid meteor shower Sep. 11 Neptune at opposition 22 The autumnal equinox occurs in the northern hemisphere at 13:31 UT Oct. 13 Mars at opposition 31 Uranus at opposition Nov. 18 Leonids meteor shower 30 Penumbral lunar eclipse visible from the Americas, E. Asia, Australia and UK. Dec. 13 Geminids meteor shower 14 Total solar eclipse visible in Chile and Argentina. 21 The winter solstice occurs in the northern hemisphere at 10:02 UT 21 Jupiter and Saturn conjunction (0.1°) 20:11 UT BAA Handbook 2020 Highlights 3 SKY DIARY m d h Phenomenon m d h Lunation 1 03 05 First Quarter Moon 1 04 09 Quadrantids Meteor Shower 1 10 15 Mercury at Superior Conjunction 1 10 19 Penumbral Lunar Eclipse 1 10 19 Full Moon 1 13 15 Saturn in Conjunction with Sun 1 13 13 Pluto in Conjunction with Sun 1 15 07 Davida at Opposition 1 17 13 Last Quarter Moon 1 23 03 Jupiter 0.4° N of Moon 1 24 02 Saturn 1.4° N of Moon 1 24 22 New Moon 1 27 19 Neptune 0.08°N of Venus

2 02 02 First Quarter Moon 2 09 08 Full Moon 2 10 14 Mercury at Greatest Elong: 18.2°E 2 15 22 Last Quarter Moon 2 18 13 Mars 0.7° S of Moon 2 19 20 Jupiter 0.9° N of Moon 2 20 14 Saturn 1.8° N of Moon 2 23 15 New Moon 2 26 02 Mercury at Inferior Conjunction

3 02 20 First Quarter Moon 3 08 12 Neptune in Conjunction with Sun 3 09 18 Full Moon 3 16 10 Last Quarter Moon 3 18 08 Mars 0.7° N of Moon 3 18 10 Jupiter 1.5° N of Moon 3 20 04 Vernal Equinox 3 20 06 Jupiter 0.7° N of Mars 3 21 09 Interamnia at Opposition 3 24 02 Mercury at Greatest Elong: 27.8°W 3 24 09 New Moon 3 24 22 Venus at Greatest Elong: 46.1°E

4 01 10 First Quarter Moon 4 02 20 Juno at Opposition 4 04 07 Hebe at Opposition 4 04 21 Mercury at Superior Conjunction 4 08 02 Full Moon 4 13 23 Cybele at Opposition 4 14 23 Last Quarter Moon

4 22 00 Lyrid Meteor Shower 4 23 02 New Moon 4 26 09 Uranus in Conjunction with Sun 4 30 21 First Quarter Moon

5 04 22 Mercury at Superior Conjunction 5 06 Eta Aquarid Meteor Shower 5 07 11 Full Moon 5 14 14 Last Quarter Moon 5 22 08 Venus 0.9°N of Mercury 5 22 18 New Moon 5 30 03 First Quarter Moon

6 03 18 Venus at Inferior Conjunction 6 04 13 Mercury at Greatest Elong: 23.6°E 6 05 19 Penumbral Lunar Eclipse 6 05 19 Full Moon 6 13 06 Last Quarter Moon 6 19 09 Venus 0.7° S of Moon 6 20 22 Summer Solstice 6 21 07 New Moon 6 21 07 Annular Solar Eclipse (not UK) 6 28 02 Iris at Opposition

4 Sky Diary BAA Handbook 2020 SKY DIARY cont'd m d h Phenomenon m d h Lunation 7 01 03 Mercury at Inferior Conjuction 7 05 05 Penumbral Lunar Eclipse 7 05 05 Full Moon 7 12 23 Last Quarter Moon 7 14 08 Jupiter at Opposition 7 15 19 Pluto at Opposition 7 20 17 New Moon 7 20 22 Saturn at Opposition 7 22 15 Mercury at Greatest Elong: 20.1°W 7 27 12 First Quarter Moon 7 31 South Delta Aquarid Meteor Shower

8 01 23 Jupiter 1.5° N of Moon 8 03 16 Full Moon 8 09 08 Mars 0.7° N of Moon 8 11 17 Last Quarter Moon 8 12 13 Perseid Meteor Shower 8 13 00 Venus at Greatest Elong: 45.8°W 8 17 15 Mercury at Superior Conjunction 8 19 03 New Moon 8 25 18 First Quarter Moon 8 28 12 Ceres at Opposition 8 29 02 Jupiter 1.4° N of Moon

9 02 05 Full Moon 9 06 05 Mars 0.03° S of Moon 9 10 09 Last Quarter Moon 9 11 20 Neptune at Opposition 9 17 11 New Moon 9 22 13 Autumnal Equinox 9 24 02 First Quarter Moon

10 01 16 Mercury at Greatest Elong: 25.8°E 10 01 21 Full Moon 10 03 03 Mars 0.7° N of Moon 10 10 01 Last Quarter Moon 10 13 23 Mars at Opposition 10 16 19 New Moon 10 22 Orionid Meteor Shower 10 23 13 First Quarter Moon 10 25 18 Mercury at Inferior Conjunction 10 31 15 Full Moon 10 31 16 Uranus at Opposition

11 05 Taurid Meteor Shower 11 08 14 Last Quarter Moon 11 10 17 Mercury at Greatest Elong: 19.1°W 11 15 05 New Moon 11 22 05 First Quarter Moon 11 30 09 Penumbral Lunar Eclipse 11 30 09 Full Moon

12 07 20 Psyche at Opposition 12 08 01 Last Quarter Moon 12 12 21 Venus 0.8° S of Moon 12 13 20 Geminid Meteor Shower 12 14 16 New Moon 12 14 16 Total Solar Eclipse (not UK) 12 20 03 Mercury at Superior Conjunction 12 21 00 First Quarter Moon 12 21 10 Winter Solstice 12 21 17 Saturn 0.1° N of Jupiter 12 22 Ursid Meteor Shower 12 30 03 Full Moon

BAA Handbook 2020 Sky Diary 5 of day 336 337 338 350 349 365 339 351 366 340 352 353 341 354 342 355 343 356 344 347 357 345 346 358 348 359 360 361 362 363 364 year 1 2 3 December 4 5 6 7 8 9 of 11 15 14 30 16 31 17 18 19 20 21 12 22 10 23 13 24 25 26 27 28 29 day month of day 311 308 306 307 309 310 322 321 323 312 324 325 313 326 314 327 315 328 316 319 329 317 330 318 320 331 332 333 334 335 year 3 1 2 4 5 6 7 8 9 November of 11 17 16 18 19 20 21 22 10 23 14 24 12 25 13 15 26 27 28 29 30 day month of day 302 275 287 286 276 288 303 277 289 304 305 290 278 291 279 292 280 281 293 284 294 282 295 283 285 296 297 298 299 300 301 year October 1 2 3 4 5 6 7 8 9 of 11 28 13 12 14 29 15 30 31 16 17 18 19 10 20 21 22 23 24 25 26 27 day month of day 245 246 274 247 259 258 248 260 249 261 262 250 263 251 264 252 253 265 256 266 254 267 255 268 257 269 270 271 272 273 year 1 2 3 4 5 6 7 8 9 September of 11 30 15 14 16 17 18 19 20 21 12 22 10 23 24 13 25 26 27 28 29 day month of day 224 223 225 240 214 226 241 242 227 244 243 215 228 216 229 217 218 230 221 231 219 232 233 220 222 234 235 236 237 238 239 year Aug 1 2 3 4 5 8 6 7 9 of 11 10 12 27 13 28 29 14 31 30 15 16 17 18 19 20 21 22 23 24 25 26 day month of day 183 184 195 196 185 197 212 186 198 213 211 199 187 200 188 201 189 190 202 193 203 191 204 205 192 194 206 207 208 209 210 year July 1 2 3 4 5 6 7 8 9 of 11 13 14 15 30 16 31 17 18 19 20 21 22 23 10 12 24 25 26 27 28 29 day month of day 154 155 153 156 167 168 157 169 158 170 171 159 172 160 173 161 162 174 175 163 165 176 177 164 166 178 179 180 181 182 year June 2 3 1 4 5 6 7 8 9 of 11 15 16 17 18 19 20 21 10 22 23 13 24 25 12 14 26 27 28 29 30 day month of day 133 122 134 149 123 135 150 136 151 124 152 137 125 138 126 127 139 140 130 141 128 142 129 131 143 132 144 145 146 147 148 year CALENDAR 2020 CALENDAR May 1 2 3 4 5 6 9 7 8 of 11 12 13 28 14 29 15 30 31 16 17 18 19 20 21 10 22 23 24 25 26 27 day month of 92 93 94 95 96 97 98 99 day 111 110 112 113 114 115 116 117 105 118 106 121 119 107 108 109 102 100 101 103 104 120 year April 1 2 3 4 5 6 7 8 9 of 11 14 15 30 16 17 18 19 20 21 22 10 12 23 13 24 25 26 27 28 29 day month of 64 63 62 61 65 77 66 78 67 79 80 68 81 69 70 82 71 83 84 72 74 85 73 75 86 76 87 88 89 90 91 day year March 4 3 2 1 5 6 7 8 9 of 11 17 18 19 20 21 10 22 23 24 12 14 25 13 15 26 16 27 28 29 30 31 day month of 42 43 58 32 44 59 45 33 60 46 34 35 47 48 36 49 37 39 50 38 40 51 41 52 53 54 55 56 57 day year February 1 2 3 4 5 6 8 9 7 of 11 12 27 13 28 14 29 15 16 17 18 19 20 10 21 22 23 24 25 26 day month 1 2 3 4 5 6 7 8 9 of 11 15 14 30 16 31 17 18 19 20 21 22 12 10 23 13 24 25 26 27 28 29 day year January 1 2 3 4 5 6 7 8 9 of 11 15 14 30 16 31 17 18 19 20 21 22 12 10 23 13 24 25 26 27 28 29 day month Fri Fri Fri Fri Fri Sat Sat Sat Sat Sat Tue Tue Tue Tue Sun Tue Sun Sun Sun Sun Sun Thu Thu Thu Thu Thu Wed Wed Wed Wed Wed Mon Mon Mon Mon Mon Mon 1 January 2020 is Julian day number 2458849.5 See also p.113 6 BAA Handbook 2020 SUN The tables on p.8–9 give the apparent RA, Dec. and diameter of the Sun, the UT of transit across the

Greenwich meridian, and P, B0, L0 where

P is the position angle of the N end of the axis of rotation. It is positive when east of the north point of the disk, negative if west;

B0 is the heliographic latitude of the centre of the disk;

L0 is the heliographic longitude of the centre of the disk.

Decrease of L0 with Time h m º h m º h m º h m º h º 0 00 0.0 1 43 1.0 3 32 2.0 5 21 3.0 6 3.3 05 0.1 54 1.1 43 2.1 32 3.1 8 4.4 16 0.2 2 05 1.2 54 2.2 43 3.2 10 5.5 27 0.3 16 1.3 4 05 2.3 54 3.3 12 6.6 38 0.4 27 1.4 16 2.4 6 05 3.4 14 7.7 49 0.5 38 1.5 27 2.5 16 3.5 16 8.8 1 00 0.6 49 1.6 38 2.6 27 3.6 18 9.9 10 0.7 3 00 1.7 49 2.7 38 3.7 20 11.0 21 0.8 10 l.8 5 00 2.8 49 3.8 22 12.1 32 0.9 21 1.9 10 2.9 7 00 3.9 24 13.2 43 1.0 32 2.0 21 3.0 10 4.0

The heliographic longitude and latitude of a spot may be conveniently estimated by the method described in J. Br. Astron. Assoc., 53, 63 (1943).

Carrington Rotation Number The dates of commencement of the synodic rotations, in continuation of Carrington’s (Greenwich Photo–Heliographic) series, are as follows: Rotation Begins Rotation Begins Rotation Begins d d d 2226 Jan. 6.37 2227 Feb. 2.71 2228 Mar. 1.05 2229 Mar. 28.36 2230 Apr. 24.64 2231 May 21.87 2232 Jun. 18.08 2233 Jul. 15.27 2234 Aug. 11.47 2235 Sep. 7.74 2236 Oct. 5.01 2237 Nov. 1.30 2238 Nov. 28.61 2239 Dec 25.93

At the date of commencement of each synodic rotation period the value of L0 is zero; that is, the prime meridian passes through the central point of the disk. The sidereal period of rotation of the Sun used in physical ephemerides is 25.38 mean solar days, after Carrington; the mean synodic rotation period is 27.2753d

BAA Handbook 2020 Sun 7 SUN

2019/20 RA Dec. Diam. Transit P B0 L0 h m ° ' ' " h m ° ° ° Dec. 29 18 30.3 –23 15 32 32 12 02 +3.78 –2.58 110.35

Jan. 3 18 52.4 –22 53 32 32 12 04 +1.35 –3.17 44.50 8 19 14.3 –22 20 32 32 12 06 –1.06 –3.74 338.65 13 19 36.1 –21 36 32 32 12 08 –3.45 –4.28 272.81 18 19 57.6 –20 42 32 31 12 10 –5.80 –4.78 206.97 23 20 18.8 –19 37 32 30 12 12 –8.07 –5.24 141.14 28 20 39.7 –18 24 32 29 12 13 –10.25 –5.67 75.31

Feb. 2 21 00.2 –17 02 32 28 12 14 –12.34 –6.05 9.48 7 21 20.4 –15 32 32 26 12 14 –14.31 –6.38 303.64 12 21 40.3 –13 56 32 25 12 14 –16.15 –6.66 237.81 17 21 59.8 –12 15 32 23 12 14 –17.86 –6.88 171.97 22 22 19.1 –10 28 32 21 12 14 –19.42 –7.06 106.13 27 22 38.1 –8 38 32 18 12 13 –20.84 –7.18 40.28

Mar. 3 22 56.8 –6 44 32 16 12 12 –22.10 –7.24 334.41 8 23 15.4 –4 48 32 14 12 11 –23.20 –7.25 268.54 13 23 33.8 –2 50 32 11 12 09 –24.14 –7.20 202.65 18 23 52.1 –0 51 32 08 12 08 –24.92 –7.10 136.75 23 0 10.4 +1 07 32 06 12 06 –25.52 –6.94 70.83 28 0 28.6 +3 05 32 03 12 05 –25.94 –6.73 4.89

Apr. 2 0 46.8 +5 01 32 00 12 03 –26.19 –6.47 298.93 7 1 05.1 +6 55 31 57 12 02 –26.26 –6.17 232.96 12 1 23.4 +8 46 31 55 12 01 –26.15 –5.82 166.96 17 1 41.9 +10 34 31 52 11 59 –25.85 –5.43 100.94 22 2 00.6 +12 17 31 49 11 58 –25.38 –5.00 34.90 27 2 19.4 +13 55 31 47 11 58 –24.71 –4.54 328.85

May 2 2 38.5 +15 27 31 44 11 57 –23.87 –4.04 262.77 7 2 57.7 +16 53 31 42 11 57 –22.84 –3.52 196.68 12 3 17.3 +18 12 31 40 11 56 –21.64 –2.98 130.56 17 3 37.0 +19 23 31 38 11 56 –20.28 –2.41 64.44 22 3 57.0 +20 26 31 36 11 57 –18.75 –1.83 358.30 27 4 17.2 +21 20 31 34 11 57 –17.08 –1.24 292.15

Jun. 1 4 37.6 +22 05 31 33 11 58 –15.27 –0.64 225.98 6 4 58.1 +22 40 31 31 11 59 –13.34 –0.03 159.81 11 5 18.8 +23 06 31 30 12 00 –11.31 +0.57 93.63 16 5 39.6 +23 21 31 29 12 01 –9.19 +1.17 27.45 21 6 00.4 +23 26 31 29 12 02 –7.00 +1.76 321.26 26 6 21.2 +23 21 31 28 12 03 –4.76 +2.34 255.08

8 Sun BAA Handbook 2020 SUN

2020/21 RA Dec. Diam. Transit P B0 L0 h m ° ' ' " h m ° ° ° Jul. 1 6 41.9 +23 05 31 28 12 04 –2.50 +2.90 188.90 6 7 02.5 +22 39 31 28 12 05 –0.24 +3.44 122.72 11 7 23.0 +22 04 31 28 12 06 +2.02 +3.96 56.54 16 7 43.2 +21 19 31 28 12 06 +4.24 +4.45 350.38 21 8 03.3 +20 25 31 29 12 06 +6.42 +4.91 284.22 26 8 23.1 +19 22 31 30 12 07 +8.53 +5.34 218.08 31 8 42.7 +18 12 31 31 12 06 +10.57 +5.73 151.94

Aug. 5 9 02.0 +16 54 31 32 12 06 +12.52 +6.08 85.81 10 9 21.1 +15 29 31 33 12 05 +14.37 +6.39 19.70 15 9 39.9 +13 58 31 35 12 04 +16.12 +6.65 313.60 20 9 58.5 +12 21 31 37 12 03 +17.75 +6.87 247.52 25 10 17.0 +10 40 31 39 12 02 +19.26 +7.04 181.45 30 10 35.2 +8 54 31 41 12 00 +20.63 +7.16 115.39

Sep. 4 10 53.3 +7 05 31 43 11 59 +21.88 +7.23 49.34 9 11 11.3 +5 13 31 46 11 57 +22.98 +7.25 343.31 14 11 29.3 +3 19 31 48 11 55 +23.93 +7.22 277.29 19 11 47.2 +1 23 31 51 11 54 +24.73 +7.13 211.28 24 12 05.2 –0 34 31 53 11 52 +25.36 +6.99 145.29 29 12 23.2 –2 30 31 56 11 50 +25.84 +6.80 79.30

Oct. 4 12 41.3 –4 27 31 59 11 49 +26.14 +6.56 13.32 9 12 59.5 –6 21 32 01 11 47 +26.26 +6.27 307.35 14 13 18.0 –8 14 32 04 11 46 +26.20 +5.93 241.39 19 13 36.7 –10 04 32 07 11 45 +25.96 +5.55 175.44 24 13 55.6 –11 50 32 10 11 44 +25.52 +5.12 109.50 29 14 14.8 –13 32 32 12 11 44 +24.89 +4.66 43.56

Nov. 3 14 34.4 –15 08 32 15 11 44 +24.06 +4.15 337.62 8 14 54.3 –16 38 32 17 11 44 +23.04 +3.62 271.70 13 15 14.5 –18 01 32 19 11 44 +21.82 +3.06 205.78 18 15 35.1 –19 17 32 22 11 45 +20.41 +2.47 139.87 23 15 56.1 –20 23 32 24 11 47 +18.83 +1.86 73.96 28 16 17.3 –21 21 32 25 11 48 +17.07 +1.24 8.06

Dec. 3 16 38.9 –22 08 32 27 11 50 +15.15 +0.60 302.16 8 17 00.7 –22 44 32 28 11 52 +13.09 –0.04 236.27 13 17 22.7 –23 10 32 30 11 54 +10.92 –0.68 170.39 18 17 44.8 –23 24 32 31 11 57 +8.64 –1.32 104.52 23 18 07.0 –23 26 32 31 11 59 +6.29 –1.94 38.65 28 18 29.2 –23 16 32 32 12 02 +3.89 –2.55 332.79

Jan. 2 18 51.3 –22 55 32 32 12 04 +1.47 –3.14 266.93

BAA Handbook 2020 Sun 9 ECLIPSES

During 2020 there will be two eclipses of the Sun and four of the Moon.

1. A penumbral lunar eclipse on January 10 will be visible from Europe, Africa, Asia and Australia. This will be the deepest penumbral eclipse of the year. Whole eclipse visible from the UK.

2. A penumbral lunar eclipse on June 5 will be visible from Europe, Africa, Asia and Australia. Eclipse at moonrise from the UK.

3. An annular solar eclipse on June 21 is visible from central East Africa and southern parts of Asia. Not visible from the UK.

4. A penumbral lunar eclipse on July 5 will be visible from the Americas and Western Europe and Africa. Eclipse at moonset from the UK.

5. A penumbral lunar eclipse on November 30 will be visible from the Americas, East Asia and Australia. Eclipse at moonset from the UK.

6. A total solar eclipse on December 14 is visible in South America (Chile and Argentina). Not visible from the UK.

Solar Eclipse Mailing List The solar eclipse community is very active and there is a plethora of websites devoted entirely to the subject. To keep up to date join the Solar Eclipse mailing list: http://groups.yahoo.com/group/SEML/ Useful eclipse websites include: For weather predictions : Jay Anderson's site: http://eclipsophile.com/ For general information : Xavier Jubier's site: http://xjubier.free.fr/en/index_en.html or Fred Espenak's: http://www.mreclipse.com/

& http://astropixels.com/

10 Eclipses BAA Handbook 2020 ECLIPSES

BAA Handbook 2020 Eclipses 11 ECLIPSES

12 Eclipses BAA Handbook 2020 ECLIPSES

BAA Handbook 2020 Eclipses 13 ECLIPSES

14 Eclipses BAA Handbook 2020 ECLIPSES

BAA Handbook 2020 Eclipses 15 ECLIPSES

16 Eclipses BAA Handbook 2020 ECLIPSES

Average Cloud Cover analysis for total solar eclipse 2020 Dec 14 Jay Anderson's site: http://eclipsophile.com/

BAA Handbook 2020 Eclipses 17 APPEARANCE OF PLANETS OF APPEARANCE

18 Appearance of Planets BAA Handbook 2020 VISIBILITY OF PLANETS The diagrams on pp 20–21, drawn for latitudes N 52° and S 35° respectively, show the times for the risings and settings of the Sun and the planets. The beginning and end of astronomical twilight (Sun 18° below horizon) is also shown. The times are in Local Mean Time and are thus in GMT (which is equal to UT) for Greenwich.

Since dates change at midnight, the dates at the top differ by one day from those at the foot. Each vertical line, followed upwards, indicates the succession of phenomena in the course of one night. Thus, at latitude N 52° on the night of June 19/20, Venus rises at 2h 40m and Mercury sets at 21h 10m, Mars rises at 00h 15m and Saturn rises at the 22h 05m. Jupiter rises at 21h 50m. Uranus rises about 1h 20m. all events occurring during twilight. Sunrise is at 03h 40m and sunset at 20h 20m, (Timings in UT derived from the diagram to nearest 5 minutes).

The UT of any phenomenon seen from elsewhere than Greenwich may be obtained as follows:

1. For longitudes east of Greenwich, subtract the longitude, expressed as time. For longitudes west of Greenwich, add the longitude expressed as time. (One degree of longitude represents 4 minutes.) This applies both to rising and to setting times.

2. Correct for latitude using a value for Δh from the table below. Add Δh, for setting times and subtract Δh for rising times. The correction should be obtained by interpolating in both latitude and declination.

Δh TABLE Latitude Dec. Latitude N 58° N 55° N 50° N 40° N 30° N 20° 0° S 20° S 25° S 30° S 40° S 45° m m m m m m ° m m m m m m +69 +29 –15 –70 –106 –134 29 +91 +45 +31 +17 –20 –43 +62 +26 –14 –66 –100 –127 28 +87 +43 +30 +16 –19 –41 +56 +24 –13 –62 –94 –120 27 +84 +41 +29 +15 –18 –39 +51 +22 –12 –58 –89 –114 26 +80 +39 +27 +14 –17 –37 +46 +20 –12 –54 –84 –107 25 +76 +37 +26 +14 –16 –35 +31 +14 –8 –40 –63 –81 20 +59 +29 +20 +11 –12 –26 +21 +10 –6 –28 –45 –58 15 +43 +21 +15 +8 –9 –19 +13 +6 –4 –18 –29 –37 10 +28 +14 +10 +5 –6 –12 +6 +3 –2 –9 –14 –18 5 +14 +7 +5 +2 –3 –6 0 0 0 0 0 0 0 0 0 0 0 0 0

If Dec. is negative, reverse the sign of Δh.

BAA Handbook 2020 Visibility of Planets 19 RISING AND SETTING OF PLANETS OF SETTING AND RISING

20 Visibility of Planets BAA Handbook 2020 RISING AND SETTING OF PLANETS OF SETTING AND RISING

BAA Handbook 2020 Visibility of Planets 21 PLANETS The ephemerides of all the planets (except the dwarf planets and the minor planets), and also the diagrams for Uranus and Neptune, are referred to the apparent equinox, so that the RA and Dec. required for setting on the telescope are obtained directly from the ephemeris. For the minor planets and comets, astrometric ephemerides referred to the equinox of 2000.0 are given. Thus they are directly comparable with star catalogues and atlases referred to this epoch; however, precession should be applied to their positions before setting on a telescope. The magnitudes given are visual. For the minor planets, it should be noted that photographic magnitudes are fainter by about 0.7. The Sky Diary lists other phenomena in chronological order. Relative positions in the Diary are geocentric. Some headings in the tables are abbreviated, as follows: a = Length of semi–major axis of orbit au CM = The longitude of central meridian °

DE = Planetocentric declination of the Earth (called ‘Tilt’ in previous Handbooks) °

DS = Planetocentric declination of the Sun ° e = Eccentricity of orbit Elong. = Elongation of the planet from the Sun (where + is east and – is west) ° H = Mean absolute asteroid magnitude i = Inclination °

LS = The planetocentric longitude of the Sun, measured in the plane of the orbit from its ascending node on the Martian equator and given as a direct and exact indicator of the Martian season. The Martian Vernal

Equinox (N. Hemisphere) occurs when LS = 0°. ° M = Mean anomaly at the epoch ° V = Visual magnitude Node = Longitude of the ascending node ° P = Position angle of the axis of rotation, or of an occultation, measured eastwards from the north point of the disk ° Peri. = Argument of perihelion ° Ph. = Phase, the fraction of the disk area that is illuminated Q = Position angle of the point of greatest defect of illumination. The position angle of the line of cusps is Q±90°. ° r = Heliocentric distance au U = Uncertainty code Δ = Distance from Earth au

λ☉ = Solar longitude ° Longitudes of central meridians refer to the geometric disks.

22 Planets BAA Handbook 2020 ELEMENTS OF PLANETARY ORBITS

KEPLERIAN ELEMENTS FOR THE EPOCH 2020 JAN. 0.5 TT

Mean Longitude Mean Longitude Mean Longitude Inclination at the of the of the to the Mean Planet Epoch Perihelion Ascending Node Ecliptic Eccentricity Distance L ϖ Ω i e a º º º º au Mercury 264.782 77.490 48.306 7.004 0.20564 0.387 Venus 44.758 131.603 76.624 3.394 0.00677 0.723 Earth 99.857 103.002 .. .. 0.01670 1.000 Mars 223.251 336.145 49.501 1.848 0.09341 1.524 Jupiter 281.305 14.771 100.515 1.304 0.04836 5.203 Saturn 294.437 92.515 113.605 2.486 0.05376 9.536 Uranus 38.929 171.036 74.025 0.772 0.04725 19.189 Neptune 348.569 44.900 131.783 1.770 0.00860 30.070

Keplerian elements are referred to the mean ecliptic and adjusted for best fit. The elements can be used for the determination of approximate positions of the planets according to Standish, E.M. and Williams, J.G.: http://ssd.jpl.nasa.gov/txt/aprx_pos_planets.pdf

Sidereal Mean Mean Perihelion Aphelion Mean Daily Sidereal Synodic Orbital Distance Distance Motion Period Period Velocity q Q n P au au ° d d km/s Mercury 0.30750 0.46670 4.09234 87.9681 115.88 47.87 Venus 0.71844 0.72822 1.60214 224.697 583.91 35.02 Earth 0.9833 1.0167 0.98561 365.253 n/a 29.78 Mars 1.3813 1.6660 0.52404 686.963 779.94 24.13 Jupiter 4.9501 5.4551 0.08306 4334.35 398.87 13.06 Saturn 9.0248 10.085 0.03337 10787.8 378.05 9.64 Uranus 18.327 20.110 0.01170 30773.0 369.64 6.79 Neptune 29.826 30.395 0.00597 60348.7 367.48 5.43

BAA Handbook 2020 Elements of Planetary Orbits 23 MERCURY Morning Apparition Greatest Elongation W Superior Conjunction Mar. 24 (28°) Jan. 10 Jul. 22 (20°) May 4 Nov. 10 (19°) Aug. 17 Dec. 20 When best seen: Northern Hemisphere: mid Jul.–early Aug., November Southern Hemisphere: early Mar.–late Apr., mid–late July 2020 RA Dec V Diam Ph. Elong. CM Δ h m ° ' " ° ° au Jan. –3 17 51.8 –24 19 –0.7 4.7 0.979 –8 66 1.420 2 18 26.3 –24 39 –0.9 4.7 0.991 –5 89 1.436 7 19 01.3 –24 25 –1.1 4.6 0.997 –2 111 1.438 Mar. 2 22 10.8 –07 45 3.0 10.5 0.059 –10 41 0.634 7 22 00.4 –09 48 1.6 9.9 0.172 –18 75 0.672 12 22 00.7 –11 02 0.9 9.1 0.294 –23 106 0.732 17 22 09.9 –11 22 0.5 8.3 0.402 –26 134 0.802 22 22 25.6 –10 51 0.3 7.6 0.492 –28 161 0.875 27 22 45.8 –9 38 0.2 7.0 0.569 –28 187 0.948 Apr. 1 23 09.2 –7 47 0.1 6.6 0.635 –26 212 1.019 6 23 35.0 –5 21 0.0 6.1 0.696 –25 235 1.087 11 0 02.9 –2 26 –0.2 5.8 0.755 –22 259 1.152 16 0 32.8 +0 56 –0.4 5.5 0.815 –19 281 1.211 21 1 05.0 +4 42 –0.7 5.3 0.876 –15 303 1.264 26 1 39.9 +8 46 –1.1 5.1 0.937 –10 324 1.304 May 1 2 17.9 +12 58 –1.7 5.0 0.985 –5 344 1.326 Jul. 5 6 31.7 +18 26 4.2 11.5 0.023 –6 323 0.581 10 6 24.1 +18 40 2.8 10.6 0.081 –12 356 0.631 15 6 24.5 +19 20 1.6 9.4 0.176 –17 26 0.707 20 6 34.6 +20 15 0.7 8.3 0.301 –20 54 0.807 25 6 54.5 +21 06 0.0 7.2 0.454 –20 80 0.923 30 7 23.6 +21 30 –0.6 6.4 0.626 –18 104 1.047 Aug. 4 8 00.2 +21 04 –1.1 5.7 0.795 –14 126 1.166 9 8 41.3 +19 36 –1.4 5.3 0.923 –9 147 1.263 14 9 23.0 +17 06 –1.8 5.0 0.987 –4 168 1.327 Oct. 28 13 51.7 –11 39 4.0 9.7 0.019 –5 196 0.686 Nov. 2 13 39.1 –8 52 1.1 8.7 0.184 –14 230 0.769 7 13 42.7 –8 22 –0.2 7.5 0.426 –18 261 0.894 12 13 59.3 –9 44 –0.6 6.5 0.636 –19 287 1.027 17 14 23.4 –12 06 –0.7 5.8 0.781 –18 311 1.146 22 14 51.4 –14 47 –0.7 5.4 0.872 –15 335 1.243 27 15 21.4 –17 24 –0.7 5.1 0.927 –13 358 1.319 Dec. 2 15 52.8 –19 47 –0.8 4.9 0.961 –10 21 1.376 7 16 25.2 –21 48 –0.8 4.7 0.981 –7 44 1.415 12 16 58.4 –23 23 –1.0 4.6 0.993 –5 66 1.439 17 17 32.5 –24 28 –1.1 4.6 0.998 –2 89 1.449

24 Mercury BAA Handbook 2020 MERCURY Evening Apparition Greatest Elongation E Inferior Conjunction Feb. 10 (18°) Feb. 26 Jun. 4 (24°) Jul. 1 Oct. 1 (26°) Oct. 25

When best seen: Northern Hemisphere: early to late Feb., mid May–mid Jun. Southern Hemisphere: late May–late Jun., early Sep.–mid Oct. 2020 RA Dec V Diam. Ph. Elong. CM Δ h m ° ' " ° ° au Jan. 12 19 36.8 –23 35 –1.2 4.7 0.998 1 134 1.425 17 20 12.3 –22 07 –1.2 4.8 0.991 4 156 1.397 22 20 47.6 –20 00 –1.1 4.9 0.971 7 178 1.351 27 21 22.0 –17 15 –1.1 5.2 0.929 11 200 1.284 Feb. 1 21 54.6 –13 59 –1.0 5.6 0.847 14 223 1.192 6 22 23.3 –10 26 –0.9 6.2 0.707 17 245 1.074 11 22 44.4 –07 05 –0.5 7.1 0.500 18 270 0.937 16 22 53.2 –04 45 0.5 8.3 0.264 16 298 0.801 21 22 47.0 –04 11 2.5 9.6 0.078 10 329 0.694 26 22 29.4 –05 29 4.7 10.5 0.008 0 5 0.637 May 6 2 59.0 +17 04 –2.2 5.1 0.999 1 4 1.321 11 3 42.3 +20 39 –1.6 5.2 0.954 7 24 1.281 16 4 25.6 +23 21 –1.1 5.5 0.851 13 45 1.209 21 5 06.3 +25 00 –0.7 6.0 0.720 17 66 1.115 26 5 42.5 +25 38 –0.3 6.6 0.589 21 88 1.012 31 6 12.9 +25 27 0.2 7.3 0.470 23 112 0.910 Jun. 5 6 36.8 +24 40 0.6 8.2 0.363 24 138 0.814 10 6 53.4 +23 29 1.1 9.2 0.265 23 165 0.729 15 7 02.2 +22 07 1.7 10.2 0.175 20 193 0.657 20 7 02.7 +20 45 2.6 11.1 0.096 16 224 0.602 25 6 55.8 +19 35 3.8 11.7 0.035 9 256 0.569 30 6 43.9 +18 45 5.0 11.9 0.008 2 289 0.560 Aug. 19 10 02.8 +13 51 –1.8 4.9 0.997 1 188 1.360 24 10 39.5 +10 11 –1.3 4.9 0.977 6 209 1.367 29 11 13.1 +6 20 –0.8 4.9 0.944 11 231 1.354 Sep. 3 11 44.1 +2 29 –0.5 5.0 0.906 14 253 1.327 8 12 12.9 –1 17 –0.3 5.2 0.867 18 275 1.290 13 12 39.9 –4 53 –0.2 5.4 0.824 20 298 1.242 18 13 05.3 –8 15 –0.1 5.6 0.778 23 322 1.186 23 13 29.2 –11 20 0.0 6.0 0.724 24 346 1.122 28 13 51.0 –14 02 0.0 6.4 0.659 25 11 1.049 Oct. 3 14 10.1 –16 16 0.1 6.9 0.576 26 36 0.968 8 14 24.8 –17 51 0.2 7.6 0.469 25 63 0.882 13 14 32.3 –18 31 0.6 8.4 0.330 21 92 0.794 18 14 29.0 –17 48 1.5 9.3 0.167 16 124 0.716 23 14 13.1 –15 18 3.7 10.0 0.028 6 159 0.671 Dec. 22 18 07.3 –25 01 –1.1 4.6 0.999 1 112 1.444 27 18 42.5 –25 00 –1.0 4.7 0.993 4 135 1.424 32 19 18.0 –24 21 –1.0 4.8 0.979 7 157 1.390 BAA Handbook 2020 Mercury 25 VENUS Superior Conjunction : – Greatest elongation E : Mar. 24 (46°) Greatest elongation W : Aug. 13 (46°) Inferior Conjunction : Jun. 3 2020 RA Dec. V Diam. Ph. Elong. Δ h m ° ' " ° au Jan. –8 20 24.5 –21 13 –4.0 12.6 0.843 33 1.327 2 21 14.7 –17 54 –4.0 13.1 0.819 35 1.272 12 22 02.4 –13 47 –4.0 13.7 0.793 37 1.214 22 22 48.0 –9 05 –4.1 14.5 0.765 39 1.153 Feb. 1 23 31.7 –4 01 –4.1 15.3 0.734 40 1.089 11 0 14.1 +1 13 –4.1 16.3 0.701 42 1.023 21 0 55.6 +6 24 –4.2 17.5 0.664 43 0.953 Mar. 2 1 36.7 +11 21 –4.2 18.9 0.623 45 0.881 12 2 17.6 +15 53 –4.3 20.7 0.578 46 0.807 22 2 58.0 +19 51 –4.3 22.8 0.528 46 0.731 Apr. 1 3 37.4 +23 06 –4.4 25.5 0.471 46 0.654 11 4 14.4 +25 31 –4.5 28.9 0.407 45 0.577 21 4 46.6 +27 05 –4.5 33.3 0.334 43 0.501 May 1 5 10.9 +27 47 –4.5 38.9 0.249 38 0.429 11 5 22.8 +27 36 –4.5 45.6 0.156 31 0.366 21 5 18.3 +26 24 –4.3 52.7 0.064 20 0.317 31 4 58.2 +24 02 –3.9 57.4 0.005 6 0.291 Jun. 10 4 33.3 +20 57 –4.0 56.6 0.014 –10 0.295 20 4 18.1 +18 26 –4.3 50.9 0.084 –23 0.328 30 4 18.4 +17 18 –4.4 43.8 0.177 –33 0.381 Jul. 10 4 32.3 +17 23 –4.5 37.3 0.268 –39 0.448 20 4 56.6 +18 09 –4.4 32.0 0.348 –43 0.521 30 5 28.2 +19 06 –4.4 27.9 0.417 –45 0.598 Aug. 9 6 05.3 +19 51 –4.3 24.7 0.478 –46 0.676 19 6 46.3 +20 06 –4.3 22.1 0.533 –46 0.754 29 7 29.9 +19 40 –4.2 20.1 0.581 –45 0.832 Sep. 8 8 15.1 +18 25 –4.2 18.4 0.626 –44 0.907 18 9 00.9 +16 20 –4.1 17.0 0.667 –43 0.981 28 9 46.7 +13 28 –4.1 15.9 0.705 –41 1.052 Oct. 8 10 32.2 +9 56 –4.1 14.9 0.740 –39 1.120 18 11 17.2 +5 51 –4.0 14.1 0.773 –37 1.186 28 12 02.1 +1 25 –4.0 13.4 0.803 –35 1.247 Nov. 7 12 47.1 –3 12 –4.0 12.8 0.830 –33 1.306 17 13 32.9 –7 48 –4.0 12.3 0.855 –31 1.361 27 14 19.9 –12 09 –4.0 11.8 0.878 –29 1.412 Dec. 7 15 08.6 –16 03 –4.0 11.4 0.899 –26 1.459 17 15 59.2 –19 17 –4.0 11.1 0.917 –24 1.502 27 16 51.7 –21 39 –3.9 10.8 0.933 –22 1.542

26 Venus BAA Handbook 2020 EARTH

Perihelion Jan. 05d 07h 49m (147,091,144 km, 0.983243564 au) Aphelion Jul. 04d 11h 56m (152,095,296 km, 1.016694252 au)

Equinoxes Mar. 20d 03h 50m Sep. 22d 13h 31m Solstices Jun. 20d 21h 44m Dec. 21d 10h 02m

Obliquity 2000 23.43929° 2020 23.43669°

MOON

PHASES OF THE MOON 2020 New Moon First Quarter Full Moon Last Quarter d h m d h m d h m d h m Jan. 03 04 45 Jan. 10 19 21 Jan. 17 12 58 Jan. 24 21 42 Feb. 02 01 42 Feb. 09 07 33 Feb. 15 22 17 Feb. 23 15 32 Mar. 02 19 57 Mar. 09 17 48 Mar. 16 09 34 Mar. 24 09 28 Apr. 01 10 21 Apr. 08 02 35 Apr. 14 22 56 Apr. 23 02 26 Apr. 30 20 38 May 07 10 45 May 14 14 03 May 22 17 39 May 30 03 30 Jun. 05 19 12 Jun. 13 06 24 Jun. 21 06 41 Jun. 28 08 16 Jul. 05 04 44 Jul. 12 23 29 Jul. 20 17 33 Jul. 27 12 33 Aug. 03 15 59 Aug. 11 16 45 Aug. 19 02 42 Aug. 25 17 58 Sep. 02 05 22 Sep. 10 09 26 Sep. 17 11 00 Sep. 24 01 55 Oct. 01 21 05 Oct. 10 00 40 Oct. 16 19 31 Oct. 23 13 23 Oct. 31 14 49 Nov. 08 13 46 Nov. 15 05 07 Nov. 22 04 45 Nov. 30 09 30 Dec. 08 00 37 Dec. 14 16 17 Dec. 21 23 41 Dec. 30 03 28

APSIDES 2020 PERIGEE APOGEE Date Diam. Date Diam. Date Diam. Date Diam. d h ' " d h ' " d h ' " d h ' " Jan. 13 20 32 39 Jul. 25 05 32 26 Jan. 2 01 29 32 Jul. 12 19 29 34 Feb. 10 20 33 09 Aug. 21 11 32 52 Jan. 29 21 29 29 Aug. 9 14 29 32 Mar. 10 06 33 28 Sep. 18 14 33 17 Feb. 26 11 29 25 Sep. 6 06 29 28 Apr. 7 18 33 29 Oct. 17 00 33 29 Mar. 24 15 29 23 Oct. 3 17 29 24 May 6 03 33 13 Nov. 14 12 33 24 Apr. 20 19 29 24 Oct. 30 19 29 24 Jun. 3 04 32 48 Dec. 12 21 33 02 May 18 08 29 28 Nov. 27 00 29 26 Jun. 30 02 32 23 Jun. 15 01 29 32 Dec. 24 17 29 30

BAA Handbook 2020 Earth / Moon 27 LUNAR LIBRATION The libration data are given in two forms: as a size and position angle (P); and as the selenographic longitude and latitude of the centre of the disk. The position angle identifies the point on the edge of the disk most displaced towards the centre of the disk from its mean position and is measured from the North point of the disk (NOT the North Pole of the Moon, which usually does not coincide with the North point of the disk) anticlockwise through celestial East, as shown in Fig. 1. In Fig. 1 N, E, S and W are directions in the sky. Selenographic longitude and latitude are analogous to geographic longitude and latitude, with latitudes of +90º and –90º identifying the Moon's North and South Poles, around which the Moon rotates. Positive longitudes are in the Moon's Eastern hemisphere and negative longitudes in the Moon's Western hemisphere, as shown in Fig. 2 for the case of zero libration. For zero libration the selenographic longitude and latitude of the centre of the disk are both 0º. Note that the Eastern hemisphere (positive selenographic longitude) of the Moon in Fig. 2 roughly corresponds to the Western side (in terms of sky direction) of the disk in Fig. 1.

Fig. 1 Fig. 2

Maximum Minimum Date Size P Sel Lon Sel Lat Date Size P Sel Lon Sel Lat d º º º º d º º º º Jan. 4.99 7.4 14 –4.0 6.2 Jan. 11.61 4.6 139 –3.8 –2.6 17.49 7.4 230 3.6 –6.4 23.94 4.9 280 4.6 1.7 Feb. 2.89 7.6 38 –5.9 4.8 Feb. 9.30 5.6 162 –3.4 –4.5 14.83 7.7 242 5.5 –5.5 21.24 5.6 289 4.6 3.2 Mar. 4.34 7.9 89 –7.9 0.5 Mar. 9.92 6.4 194 –1.1 –6.3 14.94 7.7 255 7.1 –3.0 21.49 6.5 305 3.6 5.4 23.96 6.6 331 0.6 6.6 26.94 6.5 11 –3.2 5.7 Apr. 3.07 8.3 129 –7.6 –3.4 Apr. 8.81 6.2 221 2.2 –5.8 14.61 7.6 277 7.3 2.2 24.99 5.7 36 –4.3 3.8 May 1.79 8.3 150 –6.4 –5.3 May 7.77 5.3 233 3.3 –4.1 14.28 7.8 293 5.7 5.3 23.23 5.0 52 –4.3 2.5 29.99 7.8 166 –4.7 –6.2 Jun. 5.10 4.3 240 3.4 –2.7 Jun. 11.65 7.7 301 4.6 6.2 20.00 4.8 62 –4.4 1.8 26.76 7.2 179 –2.9 –6.6 Jul. 2.98 4.0 249 3.6 –1.8 Jul. 9.54 7.5 307 3.7 6.5 16.87 5.1 54 –4.5 2.4 24.17 6.8 188 –1.8 –6.5 30.52 4.5 258 4.4 –1.3 Aug. 5.97 7.3 309 3.4 6.4 Aug. 12.07 5.3 32 –3.7 3.7 18.46 6.9 155 –4.8 –5.0 26.17 5.7 257 5.3 –2.0 Sep. 1.80 7.4 304 4.1 6.2 Sep. 8.07 5.0 26 –3.2 3.8 14.42 8.1 142 –6.6 –4.6 20.25 5.7 232 3.2 –4.7 27.96 8.1 294 5.8 5.6 Oct. 5.59 4.4 28 –2.9 3.3 Oct. 12.37 9.1 146 –7.3 –5.4 18.18 4.9 231 2.8 –4.0 24.99 9.0 289 7.0 5.7 Nov. 2.31 3.6 34 –2.6 2.6 Nov. 9.42 9.4 152 –7.1 –6.2 15.41 3.6 233 2.3 –2.7 21.86 9.4 291 7.1 6.3 29.98 3.0 40 –2.3 2.0 Dec. 7.26 8.9 160 –6.0 –6.6 Dec. 13.51 2.4 235 1.7 –1.6 19.85 9.1 294 6.3 6.6 27.39 2.8 42 –2.2 1.8

28 Lunar BAA Handbook 2020 MOONRISE AND MOONSET

On the four following pages are given the times (UT) of moonrise and moonset for longitude 0°, in the standard latitudes of N 52° and S 35°. Observers in most other latitudes can determine approximate times using the following method, where the times of moonrise and moonset are for the standard latitude in the same hemisphere as the observer.

The basis of the method is given in J. Br. Astron. Assoc., 86, 416 (1976).

N 52° S 35° 1. For a moonrise, R1, use the previous moonset, S0, and the following moonset, a Dec. a S2. Form m h m ° h m a = –2R1+S0+S2+8 0 00 0 0 00 2. For a moonset, S , use the previous moonrise, R , and the following moonrise, 1 0 0 21 1 0 12 R . Form 2 0 42 2 0 23 a = 2S –R –R +8m 1 0 2 1 03 3 0 35 3. Enter the table on the right with argument a and obtain the Moon’s Dec., by 1 25 4 0 46 mental interpolation, to 0.1º. 1 46 5 0 58 4. Enter the table on p.19 with this Dec. and the required latitude to obtain Δh. 2 07 6 1 10 2 29 7 1 21 5. Moonrise for required latitude = R1 – 1.04 Δh. 2 51 8 1 33 Moonset for required latitude = S1 + 1.04 Δh. The accuracy of the times so derived is ±3m. 3 13 9 1 45 3 35 10 1 57 3 58 11 2 09 The times thus found are for longitude 0º. 4 20 12 2 21 For other longitudes it is necessary to calculate the times of the previous (fol- 4 44 13 2 33 lowing) similar phenomenon at the standard latitude if the observer is east (west) 5 07 14 2 46 of Greenwich and then interpolate them to the observer’s longitude. 5 31 15 2 58 5 56 16 3 11 6 21 17 3 24 These calculations are most conveniently carried out using a spreadsheet or suit- 6 46 18 3 37 able applet. 7 12 19 3 51 Observers are referred to the BAA's Computing Section webpage for support in 7 39 20 4 04 doing these calculations: 8 07 21 4 18 8 35 22 4 32 9 05 23 4 46 http://britastro.org/computing/applets_moonrts.html 9 36 24 5 01 10 08 25 5 16 10 41 26 5 31 11 16 27 5 47 11 53 28 6 03 12 31 29 6 20 same opp sign }Dec{sign as a to a BAA Handbook 2020 Lunar 29 MOONRISE AND MOONSET MOONRISE AND MOONSET

LATITUDE N 52º LATITUDE N 52º

January February March April May June July August September October November December Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Day h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m 1 11:37 22:44 10:48 ––:–– 09:32 ––:–– 09:57 02:08 11:12 02:22 14:25 02:03 16:18 01:09 18:51 01:34 19:03 03:50 18:00 05:09 17:10 07:31 16:37 08:46 2 11:54 23:51 11:07 00:57 09:58 01:02 10:59 03:02 12:33 02:52 15:49 02:22 17:40 01:35 19:36 02:33 19:22 05:02 18:14 06:17 17:32 08:40 17:20 09:49 3 12:10 ––:–– 11:31 02:06 10:31 02:10 12:12 03:45 13:57 03:16 17:15 02:43 18:57 02:08 20:11 03:40 19:38 06:12 18:29 07:24 18:01 09:49 18:16 10:43 4 12:26 00:57 12:00 03:17 11:15 03:17 13:33 04:21 15:22 03:38 18:40 03:07 20:04 02:50 20:38 04:52 19:53 07:20 18:46 08:32 18:37 10:54 19:21 11:28 5 12:45 02:05 12:39 04:27 12:11 04:17 14:59 04:49 16:49 03:58 20:03 03:36 20:58 03:44 20:59 06:04 20:07 08:27 19:05 09:40 19:24 11:54 20:35 12:02

6 13:06 03:15 13:30 05:33 13:20 05:08 16:26 05:13 18:17 04:18 21:17 04:13 21:40 04:47 21:16 07:16 20:23 09:35 19:29 10:49 20:23 12:45 21:53 12:30 7 13:33 04:26 14:34 06:31 14:40 05:50 17:55 05:35 19:45 04:41 22:19 05:01 22:11 05:57 21:32 08:25 20:41 10:42 20:00 11:56 21:32 13:26 23:13 12:52 8 14:07 05:39 15:50 07:18 16:06 06:23 19:23 05:56 21:10 05:08 23:07 06:00 22:35 07:10 21:47 09:33 21:02 11:51 20:40 13:00 22:48 13:58 ––:–– 13:11 9 14:52 06:49 17:14 07:56 17:34 06:50 20:51 06:18 22:29 05:42 23:43 07:07 22:55 08:22 22:02 10:40 21:29 12:59 21:32 13:58 ––:–– 14:24 00:34 13:29 10 15:50 07:52 18:41 08:26 19:03 07:13 22:17 06:43 23:37 06:24 ––:–– 08:18 23:11 09:32 22:19 11:47 22:03 14:06 22:35 14:46 00:08 14:46 01:57 13:46

11 17:00 08:45 20:08 08:51 20:30 07:35 23:38 07:13 ––:–– 07:17 00:10 09:29 23:27 10:40 22:38 12:55 22:49 15:09 23:49 15:25 01:31 15:05 03:22 14:06 12 18:19 09:27 21:33 09:13 21:56 07:57 ––:–– 07:50 00:31 08:19 00:32 10:39 23:42 11:47 23:01 14:04 23:47 16:04 ––:–– 15:56 02:56 15:24 04:49 14:29 13 19:42 10:00 22:56 09:34 23:20 08:20 00:49 08:37 01:12 09:27 00:50 11:48 23:57 12:54 23:32 15:13 ––:–– 16:50 01:10 16:21 04:24 15:43 06:18 14:59 14 21:06 10:27 ––:–– 09:56 ––:–– 08:46 01:49 09:32 01:43 10:37 01:06 12:55 ––:–– 14:02 ––:–– 16:20 00:57 17:27 02:35 16:43 05:53 16:05 07:44 15:38 15 22:29 10:49 00:18 10:19 00:41 09:18 02:35 10:35 02:07 11:46 01:21 14:02 00:15 15:11 00:12 17:22 02:17 17:56 04:02 17:02 07:24 16:32 09:00 16:30

16 23:50 11:10 01:37 10:46 01:54 09:58 03:11 11:42 02:27 12:55 01:36 15:09 00:36 16:21 01:04 18:14 03:42 18:20 05:31 17:22 08:53 17:06 10:02 17:34 17 ––:–– 11:30 02:53 11:20 02:59 10:46 03:39 12:51 02:43 14:02 01:52 16:18 01:03 17:31 02:09 18:57 05:10 18:41 07:00 17:43 10:14 17:52 10:49 18:48 18 01:10 11:51 04:02 12:01 03:52 11:43 04:01 13:59 02:59 15:08 02:11 17:28 01:37 18:37 03:25 19:30 06:37 19:01 08:31 18:07 11:23 18:50 11:23 20:05 19 02:29 12:15 05:02 12:51 04:34 12:46 04:19 15:06 03:14 16:15 02:35 18:39 02:23 19:35 04:48 19:57 08:05 19:21 09:59 18:38 12:15 19:58 11:48 21:20 20 03:47 12:44 05:52 13:50 05:06 13:53 04:35 16:13 03:29 17:23 03:04 19:47 03:21 20:23 06:14 20:19 09:33 19:43 11:23 19:17 12:54 21:12 12:07 22:33

21 05:01 13:20 06:31 14:55 05:32 15:01 04:51 17:20 03:47 18:33 03:43 20:50 04:31 21:01 07:39 20:39 11:00 20:10 12:36 20:07 13:22 22:26 12:23 23:43 22 06:08 14:04 07:02 16:02 05:53 16:09 05:06 18:27 04:07 19:43 04:33 21:44 05:50 21:31 09:05 20:59 12:23 20:43 13:35 21:08 13:44 23:38 12:38 ––:–– 23 07:06 14:58 07:26 17:11 06:11 17:16 05:22 19:35 04:32 20:52 05:35 22:27 07:12 21:55 10:29 21:19 13:39 21:25 14:19 22:16 14:01 ––:–– 12:52 00:51 24 07:53 15:59 07:47 18:18 06:27 18:22 05:41 20:44 05:05 21:58 06:48 23:01 08:35 22:16 11:53 21:42 14:45 22:17 14:52 23:28 14:17 00:48 13:06 01:58 25 08:30 17:06 08:04 19:25 06:43 19:29 06:03 21:53 05:47 22:57 08:06 23:28 09:58 22:35 13:16 22:10 15:37 23:19 15:17 ––:–– 14:31 01:57 13:22 03:06

26 08:59 18:14 08:21 20:31 06:59 20:36 06:30 23:01 06:41 23:46 09:27 23:50 11:21 22:54 14:35 22:45 16:16 ––:–– 15:37 00:40 14:45 03:04 13:41 04:15 27 09:22 19:23 08:36 21:38 07:16 21:44 07:05 ––:–– 07:46 ––:–– 10:49 ––:–– 12:43 23:14 15:46 23:29 16:46 00:28 15:53 01:51 14:59 04:11 14:05 05:25 28 09:42 20:30 08:53 22:45 07:35 22:52 07:50 00:04 08:59 00:26 12:10 00:10 14:05 23:38 16:47 ––:–– 17:10 01:39 16:08 03:00 15:16 05:20 14:35 06:34 29 09:59 21:36 09:11 23:53 07:59 ––:–– 08:47 00:59 10:18 00:57 13:32 00:28 15:26 ––:–– 17:36 00:24 17:29 02:51 16:22 04:07 15:37 06:29 15:16 07:39 30 10:15 22:43 08:29 00:01 09:55 01:45 11:39 01:22 14:55 00:48 16:43 00:08 18:13 01:28 17:45 04:01 16:37 05:15 16:03 07:39 16:08 08:38

31 10:31 23:49 09:07 01:07 13:01 01:43 17:53 00:46 18:41 02:38 16:52 06:22 17:11 09:26

30 Lunar BAA Handbook 2020 MOONRISE AND MOONSET MOONRISE AND MOONSET

LATITUDE N 52º LATITUDE N 52º

31 10:31 23:49 09:07 01:07 13:01 01:43 17:53 00:46 18:41 02:38 16:52 06:22 17:11 09:26

BAA Handbook 2020 Lunar 31 MOONRISE AND MOONSET MOONRISE AND MOONSET

LATITUDE S 35º LATITUDE S 35º

January February March April May June July August September October November December Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Day h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m 1 10:32 23:31 12:02 23:23 11:47 22:27 13:32 23:30 13:53 ––:–– 14:16 01:46 14:02 03:01 15:12 05:13 17:04 06:11 17:48 05:42 19:25 05:33 20:12 05:19 2 11:27 23:58 12:59 23:55 12:46 23:06 14:24 ––:–– 14:32 00:33 14:50 02:55 14:44 04:10 16:11 06:08 18:02 06:43 18:43 06:08 20:23 06:05 21:08 06:05 3 12:21 ––:–– 13:58 ––:–– 13:45 23:52 15:13 00:32 15:09 01:42 15:26 04:05 15:31 05:18 17:13 06:55 18:59 07:12 19:38 06:35 21:20 06:40 21:59 06:56 4 13:17 00:26 14:58 00:32 14:44 ––:–– 15:56 01:40 15:44 02:52 16:06 05:16 16:25 06:24 18:14 07:36 19:54 07:39 20:34 07:02 22:17 07:21 22:46 07:53 5 14:14 00:54 16:00 01:14 15:41 00:45 16:36 02:50 16:18 04:02 16:52 06:27 17:23 07:23 19:13 08:11 20:49 08:05 21:31 07:31 23:11 08:08 23:28 08:55

6 15:13 01:25 17:00 02:04 16:34 01:45 17:13 04:02 16:54 05:14 17:43 07:36 18:24 08:16 20:11 08:42 21:45 08:32 22:28 08:04 ––:–– 09:01 ––:–– 09:59 7 16:14 02:00 17:57 03:03 17:22 02:52 17:49 05:15 17:33 06:26 18:39 08:40 19:26 09:01 21:07 09:11 22:41 09:00 23:26 08:41 00:01 09:59 00:05 11:04 8 17:17 02:40 18:48 04:08 18:05 04:03 18:25 06:28 18:16 07:39 19:39 09:37 20:27 09:39 22:03 09:37 23:38 09:30 ––:–– 09:23 00:47 11:02 00:39 12:10 9 18:19 03:27 19:34 05:19 18:45 05:17 19:03 07:40 19:05 08:50 20:40 10:25 21:25 10:13 22:58 10:04 ––:–– 10:05 00:22 10:13 01:28 12:08 01:11 13:17 10 19:18 04:22 20:15 06:31 19:21 06:30 19:44 08:53 19:58 09:56 21:41 11:07 22:22 10:42 23:53 10:31 00:36 10:44 01:16 11:09 02:04 13:15 01:43 14:25

11 20:12 05:24 20:52 07:43 19:57 07:42 20:29 10:03 20:56 10:56 22:40 11:42 23:17 11:10 ––:–– 11:00 01:34 11:30 02:05 12:11 02:39 14:24 02:16 15:36 12 21:00 06:31 21:27 08:54 20:33 08:54 21:18 11:10 21:55 11:48 23:37 12:14 ––:–– 11:36 00:50 11:32 02:31 12:23 02:50 13:17 03:12 15:35 02:52 16:48 13 21:42 07:41 22:02 10:04 21:11 10:05 22:12 12:12 22:55 12:32 ––:–– 12:42 00:12 12:03 01:48 12:09 03:24 13:24 03:31 14:26 03:46 16:47 03:33 18:02 14 22:19 08:51 22:37 11:12 21:52 11:14 23:09 13:06 23:54 13:10 00:32 13:08 01:08 12:31 02:48 12:52 04:13 14:30 04:08 15:37 04:21 18:01 04:20 19:13 15 22:54 10:00 23:15 12:19 22:37 12:20 ––:–– 13:53 ––:–– 13:43 01:27 13:35 02:04 13:01 03:46 13:42 04:58 15:40 04:43 16:49 05:01 19:15 05:14 20:19

16 23:28 11:08 23:56 13:25 23:27 13:22 00:07 14:34 00:51 14:12 02:22 14:02 03:02 13:36 04:43 14:40 05:38 16:51 05:18 18:01 05:45 20:29 06:14 21:17 17 ––:–– 12:15 ––:–– 14:28 ––:–– 14:19 01:05 15:09 01:46 14:40 03:18 14:31 04:02 14:15 05:36 15:44 06:15 18:03 05:53 19:15 06:36 21:38 07:19 22:06 18 00:01 13:21 00:41 15:28 00:20 15:10 02:02 15:40 02:41 15:06 04:16 15:03 05:02 15:02 06:24 16:53 06:50 19:15 06:30 20:29 07:33 22:39 08:24 22:47 19 00:36 14:26 01:31 16:22 01:16 15:54 02:58 16:09 03:36 15:32 05:15 15:40 06:01 15:56 07:07 18:04 07:24 20:27 07:12 21:42 08:35 23:31 09:27 23:22 20 01:15 15:31 02:25 17:11 02:14 16:32 03:53 16:36 04:31 16:00 06:15 16:22 06:56 16:57 07:45 19:14 08:00 21:39 07:59 22:51 09:38 ––:–– 10:28 23:52

21 01:57 16:33 03:22 17:53 03:11 17:06 04:48 17:02 05:28 16:30 07:15 17:12 07:47 18:03 08:20 20:25 08:38 22:50 08:51 23:54 10:41 00:14 11:26 ––:–– 22 02:44 17:32 04:20 18:31 04:08 17:37 05:43 17:29 06:26 17:04 08:12 18:08 08:32 19:12 08:54 21:34 09:21 23:59 09:49 ––:–– 11:41 00:51 12:23 00:19 23 03:36 18:26 05:17 19:04 05:04 18:05 06:39 17:58 07:25 17:43 09:05 19:10 09:11 20:21 09:28 22:44 10:08 ––:–– 10:49 00:49 12:40 01:22 13:18 00:45 24 04:32 19:13 06:14 19:34 05:59 18:32 07:35 18:29 08:25 18:27 09:52 20:16 09:47 21:29 10:03 23:53 11:01 01:03 11:50 01:36 13:36 01:51 14:13 01:11 25 05:29 19:55 07:09 20:01 06:53 18:58 08:33 19:04 09:23 19:18 10:34 21:23 10:21 22:37 10:41 ––:–– 11:58 02:01 12:51 02:15 14:31 02:17 15:09 01:38

26 06:28 20:31 08:04 20:28 07:48 19:26 09:32 19:44 10:18 20:16 11:11 22:30 10:53 23:45 11:24 01:01 12:57 02:52 13:50 02:49 15:26 02:43 16:06 02:07 27 07:25 21:03 08:59 20:55 08:44 19:55 10:31 20:30 11:08 21:18 11:46 23:37 11:27 ––:–– 12:12 02:07 13:57 03:36 14:47 03:19 16:22 03:09 17:05 02:39 28 08:22 21:32 09:54 21:23 09:41 20:27 11:27 21:23 11:53 22:24 12:18 ––:–– 12:02 00:52 13:06 03:08 14:57 04:13 15:42 03:47 17:18 03:36 18:03 03:16 29 09:17 22:00 10:50 21:54 10:38 21:04 12:20 22:22 12:33 23:31 12:51 00:45 12:42 02:00 14:03 04:04 15:55 04:46 16:37 04:13 18:16 04:06 19:01 04:00 30 10:12 22:26 11:37 21:46 13:09 23:26 13:09 ––:–– 13:25 01:52 13:26 03:08 15:03 04:53 16:52 05:15 17:33 04:38 19:14 04:40 19:55 04:50

31 11:06 22:54 12:35 22:34 13:43 00:38 14:16 04:13 16:04 05:35 18:28 05:05 20:44 05:46

32 Lunar BAA Handbook 2020 MOONRISE AND MOONSET MOONRISE AND MOONSET

LATITUDE S 35º LATITUDE S 35º

January February March April May June July August September October November December Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Day h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m 1 10:32 23:31 12:02 23:23 11:47 22:27 13:32 23:30 13:53 ––:–– 14:16 01:46 14:02 03:01 15:12 05:13 17:04 06:11 17:48 05:42 19:25 05:33 20:12 05:19 2 11:27 23:58 12:59 23:55 12:46 23:06 14:24 ––:–– 14:32 00:33 14:50 02:55 14:44 04:10 16:11 06:08 18:02 06:43 18:43 06:08 20:23 06:05 21:08 06:05 3 12:21 ––:–– 13:58 ––:–– 13:45 23:52 15:13 00:32 15:09 01:42 15:26 04:05 15:31 05:18 17:13 06:55 18:59 07:12 19:38 06:35 21:20 06:40 21:59 06:56 4 13:17 00:26 14:58 00:32 14:44 ––:–– 15:56 01:40 15:44 02:52 16:06 05:16 16:25 06:24 18:14 07:36 19:54 07:39 20:34 07:02 22:17 07:21 22:46 07:53 5 14:14 00:54 16:00 01:14 15:41 00:45 16:36 02:50 16:18 04:02 16:52 06:27 17:23 07:23 19:13 08:11 20:49 08:05 21:31 07:31 23:11 08:08 23:28 08:55

31 11:06 22:54 12:35 22:34 13:43 00:38 14:16 04:13 16:04 05:35 18:28 05:05 20:44 05:46

BAA Handbook 2020 Lunar 33 SUN’S SELENOGRAPHIC COLONGITUDE Day Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. º º º º º º º º º º º º 1 335.4 352.4 345.2 2.8 8.7 27.3 33.9 52.8 71.4 77.4 95.1 100.1 2 347.6 4.6 357.4 15.0 20.9 39.5 46.1 64.9 83.5 89.5 107.2 112.3 3 359.8 16.7 9.6 27.2 33.1 51.7 58.3 77.1 95.7 101.7 119.4 124.4 4 11.9 28.9 21.7 39.4 45.3 63.9 70.5 89.3 107.9 113.9 131.5 136.6 5 24.1 41.0 33.9 51.5 57.5 76.1 82.7 101.5 120.1 126.0 143.7 148.7 6 36.2 53.2 46.1 63.7 69.7 88.3 94.9 113.7 132.3 138.2 155.8 160.8 7 48.4 65.3 58.2 75.9 81.8 100.4 107.1 125.9 144.5 150.4 168.0 173.0 8 60.5 77.4 70.3 88.0 94.0 112.6 119.3 138.1 156.6 162.6 180.2 185.2 9 72.6 89.5 82.5 100.2 106.2 124.8 131.5 150.3 168.8 174.7 192.3 197.3 10 84.8 101.7 94.6 112.3 118.4 137.0 143.7 162.5 181.0 186.9 204.5 209.5 11 96.9 113.8 106.8 124.5 130.6 149.2 155.9 174.7 193.2 199.1 216.7 221.7 12 109.0 125.9 118.9 136.7 142.8 161.4 168.1 186.9 205.5 211.3 228.9 233.9 13 121.1 138.1 131.1 148.8 155.0 173.7 180.3 199.2 217.7 223.5 241.1 246.0 14 133.3 150.2 143.2 161.0 167.2 185.9 192.6 211.4 229.9 235.7 253.3 258.2 15 145.4 162.4 155.4 173.2 179.4 198.1 204.8 223.6 242.1 247.9 265.5 270.4 16 157.5 174.5 167.6 185.4 191.6 210.3 217.0 235.9 254.4 260.2 277.7 282.6 17 169.7 186.7 179.7 197.6 203.8 222.6 229.3 248.1 266.6 272.4 289.9 294.8 18 181.8 198.9 191.9 209.8 216.0 234.8 241.5 260.3 278.8 284.6 302.1 307.0 19 194.0 211.1 204.1 222.1 228.3 247.1 253.8 272.6 291.0 296.8 314.3 319.2 20 206.2 223.3 216.3 234.3 240.5 259.3 266.0 284.8 303.3 309.0 326.5 331.4 21 218.4 235.5 228.5 246.5 252.7 271.6 278.3 297.1 315.5 321.2 338.6 343.5 22 230.5 247.6 240.7 258.7 265.0 283.8 290.5 309.3 327.7 333.4 350.8 355.7 23 242.7 259.8 252.9 271.0 277.2 296.1 302.8 321.5 339.9 345.6 3.0 7.8 24 254.9 272.0 265.2 283.2 289.5 308.3 315.0 333.8 352.1 357.8 15.1 20.0 25 267.1 284.2 277.4 295.4 301.7 320.6 327.3 346.0 4.3 10.0 27.3 32.1 26 279.3 296.4 289.6 307.7 314.0 332.8 339.5 358.2 16.5 22.1 39.4 44.3 27 291.5 308.6 301.8 319.9 326.2 345.0 351.7 10.4 28.7 34.3 51.6 56.4 28 303.7 320.8 314.0 332.1 338.4 357.3 3.9 22.6 40.9 46.5 63.7 68.5 29 315.9 333.0 326.2 344.3 350.7 9.5 16.2 34.8 53.0 58.6 75.9 80.7 30 328.0 338.4 356.5 2.9 21.7 28.4 47.0 65.2 70.8 88.0 92.8 31 340.2 350.6 15.1 40.6 59.2 82.9 104.9

The Sun’s selenographic colongitude is numerically equal to the selenographic longitude of the morning terminator, measured towards celestial East from the mean centre of the disk. Its value is approximately 270° at New Moon, 0° at First Quarter, 90° at Full Moon, and 180° at Last Quarter, and should be quoted on observations. The IAU longitude of the visible morning or evening terminator, as appropriate, can be obtained from the Sun’s selenographic colongitude S as follows:

Terminator S Longitude (IAU) New Moon to First Quarter Morning 270° to 360° 360°–S East First Quarter to Full Moon Morning 0° to 90° S West Full Moon to Last Quarter Evening 90° to 180° 180°–S East Last Quarter to New Moon Evening 180° to 270° S–180° West The hourly increase in S may be taken as 0.5°

34 Lunar BAA Handbook 2020 LUNAR OCCULTATIONS Except near new and full Moon, occultations of all stars down to magnitude 6.0, visible from the three pairs of stations whose co–ordinates are tabulated below, are given in the following lists. ZC numbers refer to the Zodiacal Catalog (Astron. Papers of the American Ephemeris, X, part II, 1940). Long. (λ) Lat. (φ) Long. (λ) Lat. (φ) ° ° ° ° Greenwich 0.0 +51.5 Edinburgh –3.2 +56.0 Sydney +151.2 –33.9 Melbourne +145.1 –37.9 Dunedin +170.5 –45.9 Wellington +174.8 –41.3

Phase (Ph.). The first letter indicates whether disappearance (D) or reappearance (R). The second letter indicates whether the limb is dark (D) or bright (B). Column 7 gives the percentage Illumination of the Moon. CA is the cusp angle of the star, measured to the celestial east (anticlockwise) from the northernmost point of the Moon’s limb. The time (T) of occultation at a place Δλ degrees east and Δφ degrees north of one of the stations for which a prediction is given may be found from: T = predicted time + a Δλ + b Δφ for which the coefficients a and b are given in the table in minutes. If the observer is west of the station, Δλ is taken as negative: similarly Δφ is negative if the observer is south of the station. For distances up to 500 km the error will not usually exceed 2 minutes. If the observer is at a place between two standard stations, for both of which the coefficients a and b are given, a better result can be obtained by using the values of a and b for a latitude midway between that of the observer and the nearer station. If φ1, a1, b1 apply to this station, and (φ2, a2,b2 to the more distant, and φ is the latitude of the observer, then

Observers should note that these calculations are prone to error propagation and are best done using a spreadsheet or appropriate app. Suitable support is available on the BAA website.

Notes: Predictions have been prepared using Occult 4 software.

For stars not identified by a Greek letter, Flamsteed number or variable star designation, the HIP catalogue number is provided.

When an occultation is given for one station of a pair, but not the other, the exclusion indicates the event is probably not observable at that station due to a miss, Moon elevation too low, sky too bright, or the event occurs on the bright limb. Observability is determined by a sophisticated algorithm in ‘Occult 4’.

A more detailed list of occultations is printed monthly in the Lunar Section Circulars, available on the BAA web site. Alternatively, keen observers may like to download Occult to generate predictions for their site, from:

http://www.lunar–occultations.com/iota/occult4.htm (free for non–commercial use).

BAA Handbook 2020 Lunar 35 LUNARLunar OCCULTATIONS Occultations GREENWICH EDINBURGH E 0.0º N 51.5º W 3.2º N 56.0º Date Star V Ph. Ill. of 2020 ZC Name Moon UT a b CA UT a b CA % h m m/º m/º º h m m/º m/º º

Jan. 7 658 68 Tau 4.3 RB 89+ 16 18.3 –0.2 2.2 –47S 9 976 μ Gem 2.9 DD 99+ 17 5.6 –0.4 2.1 46N 17 17.0 –0.5 2.4 33N 9 976 μ Gem 2.9 RB 99+ 17 50.2 0.5 0.9 –61N 17 52.1 0.6 0.7 –46N 11 1277 η Cnc 5.3 RD –98 20 50.5 –0.1 3.7 28S Feb. 4 765 106 Tau 5.3 DD 77+ 21 42.6 1.6 –7.0 22S 21 21.4 1.5 –2.1 50S 5 928 TV Gem 5.9 DD 86+ 23 56.6 0.4 –4.4 29S 23 39.1 0.8 –2.7 48S 6 946 η Gem 3.5 DD 86+ 2 14.0 0.5 –0.9 65N 2 8.5 0.6 –0.7 57N 6 946 η Gem 3.5 RB 87+ 3 5.8 –0.2 –2.0 –61N 2 57.0 –0.2 –2.2 –54N 6 976 μ Gem 2.9 DD 87+ 5 28.4 0.0 –0.3 34N 6 1078 44 Gem 6.0 DD 92+ 21 9.9 1.6 –1.1 62S 21 3.0 1.3 –0.1 78S 7 1224 μ Cnc 5.3 DD 97+ 21 17.9 1.3 –0.3 77S 21 14.4 1.1 0.5 88N 8 1250 HIP 40866 5.8 DD 98+ 3 56.2 –0.8 –3.5 28S 3 43.7 –0.3 –2.9 37S 25 5 33 Psc 4.6 DD 4+ 18 35.3 9.9 9.9 25S 25 5 33 Psc 4.6 RD 4+ 18 45.9 9.9 9.9 7S 25 3536 30 Psc 4.4 DD 4+ 16 16.2 1.7 –2.3 62S 16 4.2 1.3 –1.2 81S 29 454 HIP 14439 5.6 DD 31+ 20 46.8 0.7 –0.6 73N 20 42.9 0.7 –0.1 59N Mar. 4 976 μ Gem 2.9 DD 68+ 13 0.5 –0.1 1.2 84S 13 7.0 –0.2 1.4 87N 4 976 μ Gem 2.9 RB 68+ 13 53.8 –0.1 1.8 –62S 14 2.0 0.0 1.7 –73S 11 1950 80 Vir 5.7 RD –92 23 48.0 0.6 –0.3 54N 23 44.7 0.4 –0.4 44N 14 2213 34 Lib 5.8 RD –74 1 33.5 1.6 1.9 55S 1 37.0 1.2 1.6 63S 14 2218 ζ Lib 5.5 RD –74 2 50.5 1.8 1.2 58S 2 50.3 1.5 1.1 63S 18 2836 49 Sgr 5.5 RD –31 5 13.0 0.5 –0.3 18N 5 10.7 0.1 –0.3 11N 29 668 ε Tau 3.5 DD 24+ 19 22.6 0.9 –1.6 79S 19 13.6 1.0 –1.1 87N 29 668 ε Tau 3.5 RB 25+ 20 30.9 0.6 –0.9 –74S 20 24.0 0.6 –1.3 –85S 30 817 114 Tau 4.9 DD 34+ 22 50.0 0.5 –0.2 43N 22 48.1 0.8 0.3 31N Apr. 9 2022 95 Vir 5.5 RD –99 0 53.7 2.0 0.6 65S 0 50.4 1.6 0.5 70S 13 2602 7 Sgr 5.4 RD –69 1 24.7 1.1 1.6 74S 27 929 3 Gem 5.8 DD 21+ 22 58.7 0.2 –0.2 35N 22 57.3 0.5 0.1 26N May 3 1702 ν Vir 4.0 DD 82+ 21 26.5 1.9 0.2 50N 21 22.5 1.8 0.7 42N 3 1702 ν Vir 4.0 RB 83+ 22 16.8 0.4 –2.3 –42N 22 5.4 0.2 –2.3 –36N 5 1950 80 Vir 5.7 DD 96+ 21 1.1 2.5 3.0 24N 7 2218 ζ Lib 5.5 RD –100 23 19.6 0.9 –0.3 41N 23 16.2 0.7 –0.1 37N Jun. 10 3089 χ Cap 5.3 RD –79 2 42.7 1.6 0.7 80N 2 41.3 1.3 0.8 75N 12 3343 69 Aqr 5.7 RD –61 1 56.1 0.9 2.0 67S 2 2.1 0.8 1.9 71S 12 3349 τ Aqr 4.1 DB –61 2 22.1 0.9 2.2 –48N 12 3349 τ Aqr 4.1 RD –61 3 21.2 1.6 0.9 53N 3 20.7 1.4 1.0 46N 19 668 ε Tau 3.5 RD –3 15 15.1 0.9 0.9 40S Jul. 8 3164 ε Cap 4.5 RD –91 0 35.5 1.4 1.1 87N 0 36.4 1.2 1.1 83N 11 5 33 Psc 4.6 DB –67 3 44.3 –0.3 3.2 –14N 11 5 33 Psc 4.6 RD –67 4 18.6 3.2 –1.3 36N 24 1702 ν Vir 4.0 DD 19+ 15 44.4 1.5 –0.4 80N 15 38.9 1.4 0.0 73N 28 2209 32 Lib 5.6 DD 65+ 21 6.7 1.3 –1.0 72N 20 58.5 1.2 –0.8 70N

36 Lunar Occultations BAA Handbook 2020 LUNARLunar OCCULTATIONS Occultations GREENWICH EDINBURGH E 0.0º N 51.5º W 3.2º N 56.0º Date Star V Ph. Ill. of 2020 ZC Name Moon UT a b CA UT a b CA % h m m/° m/° ° h m m/° m/° ° Aug. 3 3106 φ Cap 5.2 RD –100 23 12.4 1.6 0.5 69S 23 9.9 1.4 0.6 74S 13 654 HIP 20614 6.0 RD –35 4 55.5 –0.7 5.4 9S 14 792 109 Tau 5.0 RD –26 6 28.7 1.7 0.1 71N 6 22.5 1.7 –0.6 52N 15 929 3 Gem 5.8 RD –18 3 38.8 0.1 1.9 68S 3 46.3 0.2 1.7 79S 22 1921 65 Vir 5.9 DD 19+ 20 3.7 0.4 –1.9 67S 23 2033 κ Vir 4.2 DD 28+ 17 49.1 0.8 –1.7 43S 17 39.8 0.7 –1.4 44S 25 2302 β Sco 2.6 DD 50+ 18 11.9 1.3 –0.6 64S 18 5.8 1.1 –0.4 66S 25 2302 β Sco 2.6 RB 51+ 19 23.2 1.4 –0.8 –81S 19 15.6 1.3 –0.7 –83S Sep. 3 18 HIP 840 5.8 RD –97 21 43.7 0.8 1.8 75S 21 49.5 0.7 1.8 79S 10 752 ι Tau 4.6 RD –51 8 43.2 1.2 –0.5 74S 8 36.0 1.1 –1.0 87S 11 916 1 Gem 4.3 RD –39 12 13.9 0.4 –0.8 60S 12 8.0 0.4 –1.1 68S 13 1161 HIP 37428 5.9 RD –23 2 46.7 –0.3 2.7 32S 2 58.2 –0.1 2.2 47S 27 3164 ε Cap 4.5 DD 85+ 21 12.5 1.4 0.4 84N 21 10.3 1.2 0.5 77N 28 3175 κ Cap 4.7 DD 86+ 0 47.3 0.5 –0.7 85N 0 43.0 0.4 –0.5 71N 30 3536 30 Psc 4.4 DD 99+ 23 40.6 1.7 0.2 50S 23 37.4 1.3 0.5 62S Oct. 3 322 64 Cet 5.6 RD –96 23 24.4 1.5 1.2 88N 23 25.2 1.4 1.1 76N 3 327 65 Cet 4.4 DB –96 23 33.0 0.6 2.3 –37N 23 42.3 0.3 2.5 –24N 4 327 65 Cet 4.4 RD –96 0 41.4 1.8 0.5 83N 0 37.0 1.8 0.2 68N 7 700 HU Tau 5.9 RD –77 3 5.4 1.7 0.5 89N 3 1.5 1.6 0.0 73N 7 792 109 Tau 5.0 RD –70 21 15.0 –0.4 1.6 63S 21 23.6 –0.4 1.6 70S 20 2513 44 Oph 4.2 DD 21+ 18 17.4 1.0 –1.0 73N 18 10.0 0.9 –0.9 67N 21 2672 λ Sgr 2.8 DD 31+ 18 22.2 1.1 –0.5 61N 18 16.6 1.0 –0.5 55N Nov. 3 752 ι Tau 4.6 RD –91 19 38.1 –0.4 1.8 55S 19 47.4 –0.3 1.7 62S 6 1070 ω Gem 5.2 RD –75 1 33.5 1.0 2.2 56S 1 38.8 0.9 1.6 72S 6 1092 48 Gem 5.9 RD –73 7 20.0 1.0 –1.2 79S 11 1702 ν Vir 4.0 DB –21 5 28.6 0.7 –0.5 –64S 5 25.7 0.7 0.2 –77S 11 1702 ν Vir 4.0 RD –21 6 31.2 1.3 0.7 69S 6 30.1 1.0 0.5 80S 22 3343 69 Aqr 5.7 DD 56+ 20 51.7 1.6 –1.5 57S 20 41.8 1.3 –0.9 73S 22 3349 τ Aqr 4.1 DD 57+ 22 12.3 0.6 –0.5 80N 22 9.0 0.4 –0.2 65N 29 593 HIP 18735 5.9 DD 100+ 19 12.7 0.6 1.7 64S 19 19.2 0.4 1.8 72S Dec. 5 1308 γ Cnc 4.7 DB –79 2 40.7 1.0 –5.0 –21S 5 1308 γ Cnc 4.7 RD –79 3 8.9 1.9 5.2 23S 7 1544 46 Leo 5.4 RD –59 3 53.1 1.4 0.5 78S 3 50.5 1.1 0.2 90N 11 2022 95 Vir 5.5 RD –16 6 16.5 0.8 0.1 76N 6 15.1 0.5 0.1 68N 11 2033 κ Vir 4.2 RD –15 10 1.8 1.2 –1.0 81N 9 54.2 1.0 –0.8 80N 13 2302 β Sco 2.6 RD –2 7 29.0 0.0 –0.6 31N 7 26.2 –0.4 –1.0 21N 18 3158 37 Cap 5.7 DD 20+ 18 32.3 1.3 –1.6 65S 18 22.7 1.0 –1.1 79S 21 5 33 Psc 4.6 DD 49+ 22 2.1 0.7 –1.5 71S 21 54.4 0.6 –1.0 88S 21 3536 30 Psc 4.4 DD 48+ 19 53.5 0.9 0.4 66N 19 53.6 0.6 0.7 51N 21 3536 30 Psc 4.4 RB 48+ 21 5.1 0.9 –0.9 –84N 20 56.7 1.1 –1.4 –68N 24 322 64 Cet 5.6 DD 75+ 18 14.5 1.0 1.9 69N 18 20.6 0.7 2.0 58N 24 327 65 Cet 4.4 DD 75+ 19 34.1 1.1 1.6 66N 19 38.8 0.8 1.9 52N 24 327 65 Cet 4.4 RB 76+ 20 53.1 1.6 0.1 –86N 20 47.7 1.6 –0.3 –70N 27 593 HIP 18735 5.9 DD 91+ 4 37.2 –0.4 –2.2 47S 27 700 HU Tau 5.9 DD 95+ 21 15 1.9 –0.1 65S 21 11.6 1.4 0.7 81S

BAA Handbook 2020 Lunar Occultations 37 LUNARLunar OCCULTATIONS Occultations SYDNEY MELBOURNE E 151.2º S 33.9º E 145.1º S 37.9º Date Star V Ph. Ill. of 2020 ZC Name Moon UT a b CA UT a b CA % h m m/° m/° ° h m m/° m/° °

Jan. 4 249 ν Psc 4.5 DD 61+ 6 4.7 1.4 0.1 84N 5 57.3 1.1 –0.3 89N 8 766 105 Tau 5.8 DD 93+ 10 36.3 2.3 –0.7 77S 10 26.5 2.0 –1.0 76S 9 916 1 Gem 4.3 DD 98+ 9 23.1 1.8 –2.1 61S 19 2247 η Lib 5.4 RD –26 17 55.1 0.8 –1.4 88S 17 55.1 0.8 –1.1 71S 19 2271 θ Lib 4.1 DB –25 22 57.4 2.2 –0.4 –87S 22 48.7 1.8 –1.4 –68S 20 2271 θ Lib 4.1 RD –24 0 21.0 1.7 –0.2 81N 0 9.4 1.9 0.5 83S 28 3419 91 Aqr 4.2 DD 11+ 9 21.1 0.1 2.6 46N 9 9.8 0.3 2.6 47N 28 3419 91 Aqr 4.2 RB 11+ 10 13.2 0.3 1.0 –64N 10 6.1 0.5 1.2 –67N 28 3425 93 Aqr 4.4 DD 11+ 10 14.7 0.4 0.8 57S 10 8.1 0.7 0.9 53S

Feb. 8 1308 γ Cnc 4.7 DD 99+ 10 56.9 2.0 –3.4 53S 11 0.9 2.5 –5.9 38S 11 1701 ξ Vir 4.8 RD –92 13 2.8 0.5 –3.6 15N 16 2361 χ Oph 4.2 DB –41 17 28.7 1.8 0.0 –50N 16 2361 χ Oph 4.2 RD –41 18 10.6 –0.1 –3.7 23N 17 2498 ξ Oph 4.4 DB –31 16 28.3 0.5 –1.0 –81N 16 31.3 0.1 –1.4 –83S 17 2498 ξ Oph 4.4 RD –31 17 27.2 0.3 –2.2 53N 17 32.6 0.4 –1.7 72N 17 2509 HIP 85207 5.8 RD –30 19 39.9 1.5 –2.0 61N 19 37.5 1.5 –1.4 81N 29 404 38 Ari 5.2 DD 27+ 9 51.5 1.2 1.4 80S 9 38.0 1.5 1.2 74S

Mar. 5 1092 48 Gem 5.9 DD 76+ 10 20.3 2.3 –0.4 81S 10 9.2 2.2 –0.8 73S 16 2595 HIP 88298 5.7 RD –46 17 8.2 1.4 –1.0 89N 17 2.9 1.4 –0.5 70S 17 2747 32 Sgr 4.9 RD –37 14 50.0 –1.3 –3.2 14N 17 2754 HIP 92931 5.9 RD –36 15 52.4 0.4 –0.9 89S 15 52.7 0.4 –0.5 70S

Apr. 11 2401 HIP 81754 5.6 RD –82 16 34.2 0.8 –3.4 30N 13 2706 HIP 91405 5.8 RD –63 15 52.2 1.3 –1.1 83N 15 47.9 1.3 –0.6 77S

May 26 1099 52 Gem 5.8 DD 13+ 7 48.9 2.2 2.1 51N 29 1484 η Leo 3.5 DD 41+ 9 15.4 0.4 –2.0 35S 29 1484 η Leo 3.5 RB 41+ 10 9.1 2.2 1.7 –55S

Jun. 7 2706 HIP 91405 5.8 RD –96 10 30.8 0.1 –1.8 57N 10 36.4 0.1 –1.4 75N 8 2875 HIP 96760 6.0 RD –91 11 21.6 1.0 0.3 58S 9 3031 17 Cap 5.9 RD –83 16 12.9 1.8 4.7 31S 12 3428 95 Aqr 5.0 DB –55 17 46.2 1.3 2.3 –49N 17 31.1 1.2 1.4 –58N 12 3428 95 Aqr 5.0 RD –54 19 3.0 2.9 –0.4 68N 18 48.8 2.3 –0.5 72N 23 1170 κ Gem 3.6 DD 4+ 0 31.4 1.2 –0.6 72N 28 1813 FW Vir 5.7 DD 51+ 11 15.4 1.2 0.3 85N 11 8.7 1.1 –0.4 75S

38 Lunar Occultations BAA Handbook 2020 LUNARLunar OCCULTATIONS Occultations SYDNEY MELBOURNE E 151.2º S 33.9º E 145.1º S 37.9º Date Star V Ph. Ill. of 2020 ZC Name Moon UT a b CA UT a b CA % h m m/º m/º º h m m/º m/º º

Jul. 12 170 33 Ceti 6.0 RD –53 14 59.0 0.7 –1.8 59N 15 1.4 0.4 –1.2 72N 12 192 89 Psc 5.1 DB –51 19 43.9 1.3 2.2 –50N 19 28.6 1.1 2.0 –48N 12 192 89 Psc 5.1 RD –51 21 7.0 2.4 1.1 81N 20 48.3 2.4 0.7 79N 14 404 38 Ari 5.2 RD –33 18 50.5 1.6 –0.1 88S 18 42.7 1.2 –0.3 86S

Aug. 6 3428 94 Aqr 5.0 RD –92 10 16.7 0.0 –1.0 79N 10 354 ξ Ari 5.5 RD –59 16 4.4 1.4 –0.5 87N 15 59.1 1.0 –0.6 89S 29 2875 HIP 96760 6.0 DD 86+ 11 33.2 2.1 1.8 71N 11 14.6 2.2 0.8 82N

Sep. 2 3425 93 Aqr 4.4 RD –100 20 2.1 0.1 2.0 36S 12 1117 57 Gem 5.0 RD –26 20 3.5 2.3 –1.5 71N 19 56.7 1.9 –1.5 74N 22 2353 ψ Oph 4.5 DD 31+ 9 23.0 1.4 0.3 81S 9 13.9 1.6 –0.4 67S 22 2353 ψ Oph 4.5 RB 31+ 10 32.7 0.8 1.0 –84S 10 22.6 0.9 1.4 –74S 24 2630 1 Sgr 5.0 DD 51+ 2 40.3 0.3 –1.0 90N 24 2692 24 Sgr 5.5 DD 55+ 14 35.3 0.1 0.5 65S 14 31.8 0.3 0.6 62S 25 2836 49 Sgr 5.5 DD 64+ 11 20.4 1.8 0.9 84S 11 5.7 2.0 0.5 78S

Oct. 6 628 ω Tau 4.9 RD –80 16 58.6 2.2 0.8 70S 16 43.9 1.9 0.4 70S 9 1055 37 Gem 5.7 RD –53 15 39.2 1.4 –1.9 72N 14 1701 ξ Vir 4.8 RD –6 19 13.3 0.5 –2.4 60N 21 2589 4 Sgr 4.7 DD 26+ 7 29.2 1.4 6.4 26N 7 0.9 2.1 2.7 50N 21 2589 4 Sgr 4.7 RB 26+ 8 3.4 2.8 –4.8 –23N 21 2602 7 Sgr 5.4 DD 27+ 9 5.8 2.3 –2.3 35S 9 4.6 3.5 –7.3 16S 21 2602 7 Sgr 5.4 RB 27+ 9 44.0 –0.1 4.1 –29S 9 23.3 –0.9 9.0 –13S 21 2630 1 Sgr 5.0 DD 28+ 12 56.4 –1.0 2.4 35N 12 52.3 –0.7 2.3 39N

Nov. 10 1651 ι Leo 3.9 DB –26 19 10.2 1.6 –1.1 –69N 19 7.0 1.2 –1.5 –80N 10 1651 ι Leo 3.9 RD –26 20 20.0 1.3 –2.0 62N 20 18.8 1.4 –1.7 77N 20 3031 17 Cap 5.9 DD 33+ 12 27.7 0.2 0.8 64S 12 22.0 0.5 0.9 63S 23 3425 93 Aqr 4.4 DD 63+ 14 8.7 –1.4 5.6 10N 13 56.5 –1.0 4.3 15N 23 3425 93 Aqr 4.4 RB 63+ 14 18.8 1.5 –0.5 –25N

Dec. 4 1251 λ Cnc 5.9 RD –82 17 48.0 2.2 –0.4 78N 17 35.6 2.2 –0.3 90S 8 1734 π Vir 4.7 RD –41 20 50.1 –0.7 –3.9 16N 27 628 ω Tau 4.9 DD 93+ 11 33.2 4.8 –3.2 37S 11 17.7 4.3 –3.1 39S 27 633 53 Tau 5.5 DD 94+ 13 19.4 2.1 1.9 53N 13 0.6 1.9 1.4 56N

BAA Handbook 2020 Lunar Occultations 39 LUNARLunar OCCULTATIONS Occultations DUNEDIN WELLINGTON E 170.5º S 45.9º E 174.8º S 41.3º Date Star V Ph. Ill. of 2020 ZC Name Moon UT a b CA UT a b CA % h m m/º m/º º h m m/º m/º º

Jan. 8 752 ι Tau 4.6 DD 93+ 8 21.8 1.4 –0.9 86S 8 24.9 1.6 –0.6 90S 8 766 105 Tau 5.8 DD 93+ 11 41.0 2.4 –2.6 20S 11 43.1 2.0 –1.1 34S 13 1484 η Leo 3.5 RD –90 11 0.8 0.6 –1.3 76S 10 57.8 0.8 –1.3 82S 15 1734 pi Vir 4.7 RD –72 12 1.7 0.4 –1.8 77N 11 54.8 0.5 –1.9 70N 19 2223 γ Lib 3.9 RD –28 14 8.1 –0.1 –1.4 81S 14 1.1 –0.1 –1.4 90S 19 2271 θ Lib 4.1 DB –25 23 35.9 1.2 –1.0 –52S 23 38.6 1.2 –0.2 –69S 20 2271 θ Lib 4.1 RD –24 0 31.9 0.7 2.3 54S 0 43.7 0.6 1.6 69S 21 2547 58 Oph 4.9 RD –9 22 44.1 1.5 –4.5 24N 28 3419 91 Aqu 4.2 DD 11+ 8 57.8 0.1 1.9 80N 9 6.2 –0.1 1.8 76N

Feb. 4 700 HU Tau 5.9 DD 72+ 8 5.1 1.7 0.9 60N 8 1308 γ Cnc 4.7 DD 99+ 11 56.4 0.4 –3.3 37S 17 2498 ξ Oph 4.4 DB –31 16 58.0 1.1 –1.2 –84N 17 0.0 1.7 –0.4 –65N 17 2498 ξ Oph 4.4 RD –31 18 7.5 1.1 –2.1 60N 18 0.4 0.9 –3.0 40N

Mar. 5 1092 48 Gem 5.9 DD 76+ 10 54.9 1.2 0.4 72S 11 2.6 1.3 0.6 84S 8 1484 η Leo 3.5 RB 97+ 7 50.1 1.0 –1.3 –63S 14 2271 θ Lib 4.1 RD –70 10 44.4 0.5 0.1 32S 10 44.3 0.3 –0.6 51S 16 2595 HIP 88298 5.7 RD –46 17 48.9 1.9 0.1 75S 17 56.1 2.0 –0.5 87N 17 2754 HIP 92931 5.9 RD –36 16 18.5 1.1 –0.8 79S 16 18.9 1.2 –1.2 83N

Apr. 7 1813 FW Vir 5.7 DD 99+ 10 8.8 0.0 –3.2 52S 11 2401 HIP 81754 5.6 RD –82 17 28.7 1.4 –2.0 38N 17 15.8 9.9 9.9 3N 13 2706 HIP 91405 5.8 RD –63 16 31.9 1.8 0.1 77S 16 39.3 2.0 –0.4 85N

May 8 2271 θ Lib 4.1 RD –99 7 4.1 –0.2 –1.5 61N 6 56.0 –0.3 –1.6 52N 10 2595 HIP 88298 5.7 RD –88 10 8.4 0.0 –1.8 62N 9 59.2 –0.2 –2.1 47N 13 3078 η Cap 4.9 DB –59 14 46.5 1.5 2.4 –38N 13 3078 η Cap 4.9 RD –59 15 27.1 1.1 –4.5 27N 25 936 5 Gem 5.8 DD 6+ 5 5.4 1.1 0.4 58S 29 1484 η Leo 3.5 DD 41+ 9 36.2 –0.2 –1.4 32S 9 32.8 0.3 –0.4 55S 29 1484 η Leo 3.5 RB 41+ 10 16.1 1.3 2.6 –45S

Jun. 7 2706 HIP 91405 5.8 RD –96 11 1.8 0.8 –1.8 66N 10 55.6 0.7 –2.5 48N 8 2875 HIP 96760 6.0 RD –91 11 38.2 2.0 2.5 33S 11 50.8 1.6 0.4 61S 12 3428 95 Aqr 5.0 DB –55 18 10.6 2.2 –0.2 –67S 18 20.9 2.3 0.4 –74S 12 3428 95 Aqr 5.0 RD –54 19 21.7 0.8 2.5 48S 19 37.1 0.9 2.6 52S 23 1170 κ Gem 3.6 DD 4+ 1 12.9 1.7 –0.7 77S 1 18.1 2.0 –0.5 83S 28 1813 FW Vir 5.7 DD 51+ 11 27.0 0.3 0.0 70S 11 29.5 0.3 0.5 88S

40 Lunar Occultations BAA Handbook 2020 LUNAR OCCULTATIONS DUNEDIN WELLINGTON E 170.5º S 45.9º E 174.8º S 41.3º Date Star V Ph. Ill. of 2020 ZC Name Moon UT a b CA UT a b CA % h m m/º m/º º h m m/º m/º º

Jul. 7 3078 η Cap 4.9 RD –94 8 53.5 –0.3 –2.6 42N 12 170 33 Cet 6.0 RD –53 15 21.6 0.7 0.5 61S 15 27.4 1.1 0.4 71S 12 192 90 Psc 5.1 DB –51 20 0.9 1.9 1.0 –74S 12 192 90 Psc 5.1 RD –51 21 13.7 0.9 2.3 54S 14 404 38 Ari 5.2 DB –33 18 13.1 2.8 –2.4 –46S 18 16.1 3.0 –1.7 –53S 14 404 38 Ari 5.2 RD –33 18 57.3 –0.1 2.6 20S 19 9.5 0.3 2.6 24S 18 936 5 Gem 5.8 RD –4 19 11.1 0.8 –0.8 71S

Aug. 6 3428 95 Aqr 5.0 RD –92 10 30.7 0.6 0.1 63S 10 33.1 0.8 –0.3 79S 10 354 ξ Ari 5.5 RD –59 16 14.6 0.1 2.1 25S 16 25.5 0.5 2.1 31S 15 1030 ε Gem 3.1 RD –13 17 50.2 1.8 –3.2 45N 17 41.5 3.2 –5.4 33N 16 1170 κ Gem 3.6 RD –7 18 41.4 1.0 –1.4 84S 28 2692 24 Sgr 5.5 DD 77+ 7 24.7 1.2 –3.5 31S 7 18.7 1.7 –2.0 54S 29 2875 HIP 96760 6.0 DD 86+ 12 2.1 1.9 –0.2 50S 12 10.4 1.7 0.4 60S

Sep. 5 192 89 Psc 5.1 RD –90 10 36.2 0.5 –0.3 70S 10 36.8 0.7 –0.5 82S 12 1099 52 Gem 5.8 RD –27 15 56.2 0.5 –0.8 63S 22 2353 ψ Oph 4.5 DD 31+ 9 51.6 1.1 –1.6 32S 22 2353 ψ Oph 4.5 RB 31+ 10 22.2 –0.6 3.4 –31S 24 2630 1 Sgr 5.0 DD 51+ 3 7.3 0.9 –1.4 85S 3 7.4 1.4 –0.7 77N 29 3356 74 Aqr 5.8 DD 95+ 11 35.8 0.9 2.5 58N 11 51.6 0.7 2.9 53N

Oct. 4 384 31 Ari 5.6 RD –93 13 11.0 1.5 0.1 77S 13 19.1 1.9 0.3 80S 6 628 ω Tau 4.9 RD –80 17 14.0 1.4 2.2 29S 17 31.1 1.7 2.4 36S 9 1055 37 Gem 5.7 RD –53 16 17.7 1.3 –0.5 61S 16 22.1 1.7 –0.3 65S 14 1701 ξ Vir 4.8 RD –6 19 52.3 0.9 –1.8 74N 19 47.1 0.9 –2.1 64N 21 2589 4 Sgr 4.7 DD 26+ 7 27.9 1.2 1.1 90S 7 38.6 1.0 1.5 79N 21 2589 4 Sgr 4.7 RB 27+ 8 36.5 0.7 1.4 –88S 8 45.1 0.7 1.0 –83N 21 2630 1 Sgr 5.0 DD 28+ 12 26.5 –0.5 1.1 88N

Nov. 10 1651 ι Leo 3.9 DB –26 20 4.5 2.6 0.3 –51N 10 1651 ι Leo 3.9 RD –26 21 1.6 0.9 –1.2 56N 20 57.2 0.4 –2.1 36N 19 2834 χ Sgr 5.0 DD 19+ 0 51.3 0.4 –3.8 28S 23 3425 93 Aqr 4.4 DD 63+ 13 29.1 –0.1 2.1 59N 13 38.1 –0.3 2.2 54N

Dec. 8 1707 4 Vir 5.3 RD –44 13 48.3 0.4 –2.5 45N 25 384 31 Ari 5.6 DD 80+ 8 5.8 2.1 0.1 84S 27 633 53 Tau 5.5 DD 93+ 13 32.4 1.3 1.7 74N 13 46.7 1.3 2.0 66N

BAA Handbook 2020 Lunar Occultations 41 GRAZING LUNARLunar Occultations OCCULTATIONS The map shows the tracks of stars to magnitude 8.0 which will graze the Moon’s limb and where the Moon is less than 90 percent sunlit, has an altitude of more than 5°. The track commences in the West, and the Time (UT) is near the centre of the region. Tracks marked on the map as `A´ indicate the star is at a low altitude. Tracks marked with a `B´ indicate the bright limb is close. Small or negative cusp angles indicate the graze occurs at the terminator. The track is terminated if the altitude (A) is low or when the sky (S) is bright. The Altitude (Alt) column is the approximate elevation of the Moon, as a guide to observability.

Accuracy: Recording events to a UT accuracy of 0.2s or better are desirable. Observers using video or planetary webcams, with UT time stamps, are invited to contact the Lunar Section for assistance with light curve analysis and reporting of times. Visual Observers: Individuals and teams should continue to send timings to the Lunar Section.

General circumstances for the events can be judged from personal planetarium software. More details of grazes may be computed using software for non–commercial use from:

http://www.lunar–occultations.com/iota/occult4.htm http://www.doa–site.nl/

Observers positioned on or very near the tracks may see the star disappear and reappear several times at the edge of features on the Moon’s limb. Observations continue to be valuable in the study and refinement of the shape and motion of the Moon, and in the detection of double or multiple stars, particularly during grazes. Potential observers are encouraged to contact Tim Haymes at [email protected] for additional information. A brief notification of success or failure of the observing attempt would be appreciated. Key to the Map 2020 Star N or S Cusp name ZC* Time† V Sunlit‡ limit angle† sp alt. MM DD h m % ° 1 S139322 1923 Jan. 17 02 31 7.0 –54 S 6.2 K0 15 2 106 Tau 765 Feb. 04 21 47 5.3 +77 S 4.3 A5 56 3 S139669 2008 Feb. 14 01 15 6.5 –70 S 9.5 K0 12 4 33 Psc 5 Feb. 25 18 39 4.6 +4 S 16.5 K1 8 5 S109952 XZ2150 Feb. 27 18 33 7.4 +14 S 11.5 K0 28 6 S78561 XZ9444 Mar. 04 20 49 7.4 +70 S 3.5 K2 60 7 S159358 (d) XZ21455 Mar. 14 03 34 7.2 –74 S 12.7 K1 21 8 12 Gem 964 Mar. 31 21 23 6.9 +44 N 0.5 A0 40 9 S98862 1462 May 01 23 18 7.3 +62 N 3.4 K0 34 10 33 Psc 5 Jul. 11 03 55 4.6 –67 N 10.3 K1 30 11 26 Ceti 150 Sep. 05 04 34 6.1 –92 N 17.8 F1 34 12 25 Ari 362 Sep. 07 00 59 6.4 –80 N 15.3 F5 38 13 S79805 1195 Nov. 06 23 55 6.8 –65 N 9.9 B8 26 14 S79864 (d) 1208 Nov. 07 02 24 6.4 –65 N 6.8 K1 48 15 S80552 1342 Nov. 08 03 27 7.6 –54 N 4.0 G5 47 16 S165259 3336 Nov. 22 18 43 7.1 +56 S 5.7 K4 20 17 S99144 1532 Dec. 07 01 02 7.5 –60 N 2.1 K0 24 18 38 Cap 3160 Dec. 18 18 47 6.7 +19 S 9.6 F7 7 19 S165586 3414 Dec. 20 18 59 7.5 +38 S 9.5 A8 21

* Numbers taken from the Robertson Zodiacal Catalog or the Extended Zodiacal Catalog d = double, m = multiple, u = unconfirmed. † Precise times and cusp angles are dependent on location ‡ a negative number indicates a waning Moon sp star spectrum classification alt. is dependent on location and is provided as a guide

42 Grazing Lunar Occultations BAA Handbook 2020 GRAZING LUNARLunar Occultations OCCULTATIONS

BAA Handbook 2020 Grazing Lunar Occultations 43 MARS

Opposition: Oct. 13

2020 RA Dec. V Diam P Q Ph. DE DS LS h m ° ' " ° ° ° ° ° Jan. –8 15 20.2 –17 55 1.6 4.2 38 285 1.0 12.8 20.4 124.80 2 15 47.7 –19 36 1.6 4.3 37 283 1.0 10.1 19.1 129.60 12 16 15.8 –21 02 1.5 4.4 36 280 0.9 7.4 17.7 134.40 22 16 44.6 –22 10 1.4 4.6 34 278 0.9 4.5 16.1 139.40 Feb. 1 17 13.9 –23 00 1.4 4.8 31 275 0.9 1.5 14.4 144.30 11 17 43.6 –23 30 1.3 5.0 28 272 0.9 –1.4 12.5 149.40 21 18 13.6 –23 40 1.2 5.2 25 268 0.9 –4.3 10.5 154.50 Mar. 2 18 43.7 –23 29 1.1 5.5 21 265 0.9 –7.2 8.5 159.80 12 19 13.7 –22 57 1.0 5.8 17 262 0.9 –10.0 6.3 165.10 22 19 43.6 –22 06 0.9 6.1 13 260 0.9 –12.7 4.0 170.50 Apr. 1 20 13.0 –20 55 0.8 6.4 9 257 0.9 –15.2 1.7 176.00 11 20 42.0 –19 28 0.7 6.8 5 255 0.9 –17.4 –0.7 181.70 21 21 10.4 –17 45 0.5 7.2 0 253 0.9 –19.4 –3.1 187.40 May 1 21 38.2 –15 50 0.4 7.6 356 251 0.9 –21.0 –5.6 193.20 11 22 05.3 –13 44 0.3 8.1 351 249 0.9 –22.4 –8.0 199.10 21 22 31.7 –11 31 0.1 8.6 347 248 0.9 –23.3 –10.4 205.00 31 22 57.4 –9 13 0.0 9.2 343 247 0.8 –23.9 –12.7 211.10 Jun. 10 23 22.2 –6 54 –0.2 9.9 339 247 0.8 –24.0 –14.9 217.20 20 23 46.2 –4 36 –0.3 10.6 336 247 0.8 –23.8 –17.0 223.40 30 0 09.2 –2 23 –0.5 11.4 332 247 0.8 –23.3 –18.9 229.70 Jul. 10 0 31.0 +0 18 –0.7 12.2 330 247 0.8 –22.5 –20.6 235.90 20 0 51.3 +1 36 –0.8 13.2 328 248 0.9 –21.5 –22.1 242.30 30 1 09.7 +3 17 –1.0 14.3 326 249 0.9 –20.4 –23.3 248.60 Aug. 9 1 25.6 +4 41 –1.3 15.6 325 250 0.9 –19.3 –24.3 255.00 19 1 38.3 +5 46 –1.5 17.0 324 251 0.9 –18.4 –24.9 261.30 29 1 46.9 +6 29 –1.7 18.4 324 253 0.9 –17.7 –25.2 267.60 Sep. 8 1 50.6 +6 50 –2.0 19.9 324 254 0.9 –17.5 –25.1 273.90 18 1 48.7 +6 47 –2.2 21.3 324 256 1.0 –17.7 –24.8 280.10 28 1 41.4 +6 24 –2.4 22.3 324 259 1.0 –18.5 –24.1 286.30 Oct. 8 1 30.0 +5 49 –2.6 22.6 325 272 1.0 –19.6 –23.2 292.50 18 1 17.3 +5 13 –2.5 22.0 325 41 1.0 –21.0 –22.0 298.50 28 1 06.3 +4 52 –2.3 20.7 326 61 1.0 –22.2 –20.5 304.50 Nov. 7 0 59.4 +4 53 –1.9 19.0 326 65 1.0 –23.2 –18.9 310.30 17 0 57.5 +5 21 –1.6 17.1 327 66 1.0 –23.8 –17.2 316.10 27 1 00.5 +6 13 –1.3 15.3 326 67 0.9 –24.1 –15.3 321.80 Dec. 7 1 07.8 +7 24 –0.9 13.6 325 68 0.9 –24.1 –13.2 327.40 17 1 18.7 +8 51 –0.6 12.2 324 68 0.9 –23.7 –11.2 332.90 27 1 32.5 +10 29 –0.4 11.0 323 69 0.9 –23.0 –9.0 338.30

44 Mars BAA Handbook 2020 LONGITUDE OF THE CENTRAL MERIDIAN OF MARS

Day Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. ° ° ° ° ° ° ° ° ° ° ° ° 1 44.5 103.5 181.8 239.7 305.8 1.3 67.7 128.3 196.8 286.1 12.2 97.5 2 34.8 93.8 172.0 229.9 296.0 351.5 57.9 118.7 187.5 277.2 3.2 88.1 3 25.1 84.1 162.3 220.1 286.2 341.7 48.2 109.2 178.3 268.4 354.3 78.8 4 15.4 74.4 152.6 210.3 276.4 331.9 38.5 99.7 169.1 259.6 345.3 69.4 5 5.7 64.7 142.9 200.6 266.6 322.1 28.8 90.1 160.0 250.8 336.3 60.0 6 355.9 54.9 133.1 190.8 256.8 312.3 19.0 80.6 150.8 242.0 327.3 50.6 7 346.2 45.2 123.4 181.0 246.9 302.4 9.3 71.1 141.6 233.2 318.3 41.2 8 336.5 35.5 113.7 171.2 237.1 292.6 359.6 61.6 132.5 224.4 309.2 31.8 9 326.8 25.8 103.9 161.4 227.3 282.8 349.9 52.1 123.4 215.6 300.2 22.4 10 317.1 16.1 94.2 151.7 217.5 273.0 340.2 42.6 114.3 206.8 291.1 12.9 11 307.4 6.4 84.5 141.9 207.7 263.2 330.5 33.2 105.2 198.0 282.0 3.5 12 297.7 356.7 74.7 132.1 197.8 253.4 320.8 23.7 96.1 189.2 272.9 354.0 13 288.0 347.0 65.0 122.3 188.0 243.6 311.1 14.3 87.0 180.4 263.8 344.6 14 278.2 337.3 55.2 112.5 178.2 233.8 301.4 4.8 78.0 171.6 254.7 335.1 15 268.5 327.5 45.5 102.7 168.4 224.0 291.8 355.4 68.9 162.8 245.6 325.6 16 258.8 317.8 35.8 92.9 158.5 214.2 282.1 346.0 59.9 154.0 236.4 316.1 17 249.1 308.1 26.0 83.1 148.7 204.4 272.4 336.5 50.9 145.2 227.2 306.6 18 239.4 298.4 16.3 73.3 138.9 194.6 262.8 327.1 41.9 136.4 218.1 297.1 19 229.7 288.7 6.5 63.5 129.0 184.8 253.1 317.8 32.9 127.6 208.9 287.6 20 220.0 279.0 356.8 53.7 119.2 175.1 243.5 308.4 24.0 118.7 199.7 278.1 21 210.3 269.3 347.0 43.9 109.4 165.3 233.8 299.0 15.0 109.9 190.4 268.6 22 200.6 259.5 337.3 34.1 99.6 155.5 224.2 289.7 6.1 101.1 181.2 259.1 23 190.9 249.8 327.5 24.3 89.7 145.7 214.6 280.3 357.1 92.2 172.0 249.5 24 181.1 240.1 317.8 14.5 79.9 136.0 205.0 271.0 348.2 83.4 162.7 240.0 25 171.4 230.4 308.0 4.7 70.1 126.2 195.4 261.7 339.3 74.5 153.4 230.5 26 161.7 220.7 298.2 354.9 60.3 116.4 185.8 252.3 330.4 65.7 144.1 220.9 27 152.0 210.9 288.5 345.1 50.4 106.7 176.2 243.1 321.5 56.8 134.8 211.3 28 142.3 201.2 278.7 335.3 40.6 96.9 166.6 233.8 312.6 47.9 125.5 201.8 29 132.6 191.5 269.0 325.5 30.8 87.2 157.0 224.5 303.8 39.0 116.2 192.2 30 122.9 259.2 315.7 21.0 77.4 147.4 215.2 294.9 30.1 106.9 182.7 31 113.2 249.4 11.2 137.8 206.0 21.1 173.1

CHANGE OF LONGITUDE IN INTERVALS OF MEAN TIME

h ° h ° m ° m ° m ° 1 14.62 7 102.34 10 2.44 1 0.24 6 1.46 2 29.24 8 116.96 20 4.87 2 0.49 7 1.71 3 43.86 9 131.58 30 7.31 3 0.73 8 1.95 4 58.48 10 146.21 40 9.75 4 0.97 9 2.19 5 73.10 11 160.83 50 12.18 5 1.22 10 2.44 6 87.72 12 175.45 60 14.62

BAA Handbook 2020 Mars 45 ASTEROIDS

ORBITAL ELEMENTS

Observers with binoculars or small telescopes may find these data useful in locating some of the brighter asteroids.

The data below, for asteroids brighter than magnitude 9.5 at opposition, have been extracted from the Minor Planet Center’s Minor Planet and Comet Ephemeris Service at:

http://www.minorplanetcenter.net/iau/MPEph/MPEph.html

Equinox of the elements J2000 Epoch of the elements JD 2458600.5, 2019 Apr. 27.0 TT

No. Name a e i Node Peri. M au º º º º 5 Astraea 2.574 0.191 5.367 141.577 358.688 282.366 7 Iris 2.385 0.231 5.524 259.563 145.265 140.420 8 Flora 2.202 0.156 5.887 110.889 285.287 194.883 11 Parthenope 2.453 0.100 4.630 125.547 195.550 278.931 15 Eunomia 2.644 0.186 11.752 292.934 98.499 283.388 16 Psyche 2.924 0.134 3.096 150.046 228.823 288.336 19 Fortuna 2.443 0.158 1.574 211.144 182.065 197.339 27 Euterpe 2.347 0.173 1.584 94.788 356.450 335.316 68 Leto 2.783 0.186 7.969 44.133 304.491 261.610 471 Papagena 2.894 0.229 15.017 83.813 315.136 246.024 532 Herculina 2.773 0.175 16.315 107.533 76.303 344.216

WEBSITE More information on asteroids and dwarf planets can be found on the website of the Asteroids and Remote Planets Section at: http://www.britastro.org/asteroids/

46 Asteroids BAA Handbook 2020 ASTEROID EPHEMERIDES The geocentric data below, for asteroids listed on p.46, have been extracted from the Minor Planet Center Ephemeris Service at: http://www.minorplanetcenter.net/iau/MPEph/MPEph.html

Equinox of the elements J2000 Epoch of the elements JD 2458600.5, 2019 Apr. 27.0 TT

5 Astraea

2020 RA Dec. Δ r Elong. V h m s º ' " au au º Jan. 1 8 23 25.5 +14 41 47 1.188 2.120 154.7 9.6 11 8 16 16.7 +15 29 04 1.142 2.111 166.5 9.2 21 8 07 27.4 +16 28 04 1.120 2.103 176.3 8.9 31 7 58 25.3 +17 32 00 1.124 2.096 167.5 9.2 Feb. 10 7 50 47.7 +18 33 35 1.152 2.091 155.6 9.5

20 7 45 49.8 +19 27 22 1.203 2.087 144.3 9.7 Mar. 1 7 44 16.8 +20 10 03 1.272 2.084 133.8 10.0 11 7 46 21.8 +20 40 08 1.356 2.083 124.2 10.2 21 7 51 51.6 +20 57 10 1.451 2.083 115.4 10.4

7 Iris 2020 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Apr. 20 18 55 58.8 –22 27 47 2.294 2.763 107.2 10.5 30 18 59 31.8 –22 07 09 2.151 2.747 116.1 10.3 May 10 19 00 31.8 –21 48 04 2.016 2.729 125.5 10.1 20 18 58 46.7 –21 31 01 1.895 2.712 135.5 9.9 30 18 54 11.3 –21 16 04 1.791 2.693 146.1 9.7

Jun. 9 18 46 58.0 –21 02 45 1.708 2.674 157.3 9.4 19 18 37 36.6 –20 50 12 1.650 2.654 168.9 9.1 29 18 26 59.1 –20 37 41 1.618 2.634 177.1 8.8 Jul. 9 18 16 15.3 –20 25 02 1.613 2.612 166.5 9.1 19 18 06 34.4 –20 12 45 1.635 2.591 154.8 9.3

29 17 58 57.2 –20 01 56 1.680 2.569 143.5 9.5 Aug. 8 17 54 03.8 –19 53 34 1.745 2.546 132.9 9.6 18 17 52 10.8 –19 48 06 1.826 2.523 122.8 9.8 28 17 53 20.9 –19 45 18 1.918 2.499 113.5 10.0 Sep. 7 17 57 23.6 –19 44 15 2.018 2.475 104.8 10.1

17 18 04 03.0 –19 43 35 2.121 2.450 96.7 10.2 27 18 13 03.0 –19 41 46 2.226 2.425 89.0 10.3 Oct. 7 18 24 05.2 –19 37 06 2.329 2.400 81.8 10.4 17 18 36 53.7 –19 28 02 2.430 2.374 74.9 10.4 27 18 51 14.3 –19 13 03 2.525 2.349 68.4 10.5

BAA Handbook 2020 Asteroids 47 ASTEROID EPHEMERIDES

8 Flora 2020 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jun. 19 0 59 11.5 +1 15 17 1.982 1.960 73.9 10.5 29 1 17 26.4 +2 37 35 1.872 1.946 78.6 10.4 Jul. 9 1 35 08.1 +3 50 44 1.762 1.933 83.6 10.3 19 1 52 06.9 +4 53 18 1.652 1.920 88.7 10.2 29 2 08 07.7 +5 43 42 1.544 1.909 94.2 10.0

Aug. 8 2 22 53.7 +6 20 45 1.439 1.899 100.0 9.8 18 2 36 03.0 +6 43 21 1.337 1.889 106.3 9.6 28 2 47 07.3 +6 50 34 1.239 1.881 113.1 9.4 Sep. 7 2 55 37.6 +6 42 21 1.148 1.874 120.6 9.2 17 3 01 01.4 +6 19 10 1.066 1.868 128.9 9.0

27 3 02 49.2 +5 42 53 0.995 1.864 137.9 8.7 Oct. 7 3 00 48.7 +4 57 35 0.938 1.861 147.7 8.4 17 2 55 10.3 +4 09 18 0.898 1.859 157.8 8.2 27 2 46 44.8 +3 26 44 0.878 1.858 166.3 8.0 Nov. 6 2 37 03.1 +2 59 12 0.880 1.859 166.9 8.0

16 2 27 50.8 +2 53 47 0.905 1.861 158.8 8.2 26 2 20 47.7 +3 14 06 0.950 1.865 148.6 8.5 Dec. 6 2 16 57.6 +3 59 13 1.014 1.869 138.5 8.7 16 2 16 44.3 +5 05 19 1.093 1.875 129.0 9.0 26 2 20 06.4 +6 27 48 1.184 1.882 120.3 9.3

11 Parthenope 2020 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Aug. 28 2 27 15.9 +8 12 21 1.642 2.291 117.5 10.5 Sep. 7 2 29 33.9 +7 52 28 1.552 2.300 126.7 10.3 17 2 28 52.1 +7 18 31 1.474 2.310 136.6 10.1 27 2 25 08.5 +6 32 25 1.412 2.319 147.2 9.9 Oct. 7 2 18 43.6 +5 38 10 1.371 2.329 158.2 9.7

17 2 10 19.7 +4 41 26 1.354 2.339 168.6 9.5 27 2 01 03.9 +3 49 31 1.363 2.349 171.0 9.4 Nov. 6 1 52 13.1 +3 09 30 1.398 2.360 161.7 9.7 16 1 44 54.7 +2 46 26 1.458 2.370 150.6 10.0 26 1 39 58.6 +2 42 52 1.541 2.381 139.7 10.2

Dec. 6 1 37 48.1 +2 58 37 1.642 2.392 129.4 10.5

48 Asteroids BAA Handbook 2020 ASTEROID EPHEMERIDES

15 Eunomia 2020 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Sep. 17 7 35 07.0 +26 06 20 2.588 2.314 63.1 10.1 27 7 51 16.6 +25 09 03 2.493 2.331 69.1 10.1 Oct. 7 8 05 53.7 +24 08 31 2.392 2.348 75.4 10.1 17 8 18 46.9 +23 06 34 2.286 2.366 82.2 10.0 27 8 29 41.8 +22 05 05 2.178 2.385 89.4 9.9

Nov. 6 8 38 24.1 +21 05 57 2.069 2.404 97.2 9.8 16 8 44 36.3 +20 10 59 1.961 2.423 105.6 9.7 26 8 47 59.7 +19 21 54 1.859 2.442 114.7 9.5 Dec. 6 8 48 20.0 +18 39 56 1.765 2.462 124.6 9.3 16 8 45 27.7 +18 05 49 1.683 2.481 135.3 9.2

26 8 39 27.8 +17 39 25 1.620 2.501 146.7 9.0

16 Psyche 2020 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Oct. 7 5 25 40.7 +19 17 13 2.068 2.612 112.0 10.5 17 5 28 21.7 +19 06 16 1.962 2.621 121.2 10.4 27 5 28 12.0 +18 53 33 1.868 2.631 131.1 10.2 Nov. 6 5 25 09.5 +18 40 00 1.790 2.641 141.8 10.0 16 5 19 25.6 +18 26 20 1.731 2.651 153.1 9.8

26 5 11 33.6 +18 13 22 1.697 2.662 164.7 9.6 Dec. 6 5 02 28.7 +18 02 07 1.690 2.673 174.8 9.4 16 4 53 17.3 +17 53 50 1.712 2.684 168.9 9.6 26 4 45 08.5 +17 50 06 1.762 2.696 157.4 9.8

19 Fortuna 2020 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Aug. 8 23 36 26.8 –0 14 26 1.306 2.189 141.1 10.4 18 23 32 55.9 –0 35 52 1.231 2.175 151.6 10.1 28 23 26 53.0 –1 16 15 1.176 2.161 162.9 9.8 Sep. 7 23 19 3.4 –2 11 03 1.143 2.149 174.4 9.4 17 23 10 33.8 –3 13 04 1.135 2.136 172.8 9.4

27 23 02 45.8 –4 13 08 1.152 2.125 161.0 9.7 Oct. 7 22 56 53.8 –5 02 39 1.191 2.114 149.6 10.0 17 22 53 46.7 –5 35 46 1.249 2.104 138.8 10.2 27 22 53 49.7 –5 49 16 1.324 2.095 128.8 10.5

BAA Handbook 2020 Asteroids 49 ASTEROID EPHEMERIDES

27 Euterpe 2020 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jan. 31 12 10 09.6 +1 20 03 1.390 2.146 128.5 10.4 Feb. 10 12 08 36.5 +1 42 47 1.321 2.165 139.1 10.2 20 12 03 52.4 +2 24 47 1.269 2.184 150.5 10.0 Mar. 1 11 56 25.6 +3 21 42 1.238 2.203 162.5 9.7 11 11 47 16.6 +4 25 48 1.232 2.223 174.5 9.5

21 11 37 43.4 +5 27 51 1.252 2.242 171.7 9.6 31 11 29 07.8 +6 19 14 1.298 2.262 159.8 9.9 Apr. 10 11 22 37.0 +6 53 47 1.368 2.282 148.3 10.2 20 11 18 47.0 +7 09 03 1.458 2.301 137.6 10.5

68 Leto 2020 RA Dec. ∆ r Elong. V h m s ° ´ " au au ° Aug. 18 1 03 06.7 –3 35 59 1.468 2.268 131.4 10.5 28 1 01 50.7 –3 47 18 1.394 2.271 141.1 10.3 Sep. 7 0 57 40.4 –4 07 33 1.337 2.274 151.4 10.0 17 0 50 57.4 –4 32 10 1.301 2.278 161.9 9.8 27 0 42 30.2 –4 54 52 1.289 2.283 170.5 9.5

Oct. 7 0 33 29.5 –5 09 01 1.302 2.290 168.5 9.6 17 0 25 09.7 –5 09 28 1.340 2.297 158.7 9.9 27 0 18 38.1 –4 53 07 1.401 2.305 148.0 10.2 Nov. 6 0 14 37.8 –4 19 25 1.484 2.314 137.6 10.5

471 Papagena 2020 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Aug. 28 2 46 12.5 –4 41 16 1.647 2.273 115.6 10.4 Sep. 7 2 50 48.6 –5 07 59 1.547 2.263 123.4 10.2 17 2 52 31.7 –5 41 43 1.458 2.255 131.6 10.0 27 2 51 07.6 –6 17 40 1.383 2.247 140.2 9.9 Oct. 7 2 46 39.9 –6 49 10 1.326 2.241 148.7 9.7

17 2 39 32.5 –7 08 33 1.289 2.236 155.8 9.5 27 2 30 38.4 –7 07 58 1.275 2.232 159.2 9.5 Nov. 6 2 21 13.6 –6 41 54 1.286 2.230 156.6 9.5 16 2 12 37.0 –5 48 46 1.320 2.229 149.6 9.6 26 2 05 58.7 –4 30 24 1.376 2.230 140.8 9.8

Dec. 6 2 02 02.4 –2 51 33 1.452 2.232 131.7 10.0 16 2 01 05.2 –0 57 44 1.544 2.235 122.7 10.2 26 2 03 07.0 +1 06 07 1.648 2.239 114.2 10.4

50 Asteroids BAA Handbook 2020 ASTEROID EPHEMERIDES

532 Herculina 2020 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Apr. 20 19 09 42.6 –14 44 14 2.192 2.609 103.0 10.5 30 19 14 18.4 –14 55 17 2.084 2.627 111.6 10.4 May 10 19 16 23.7 –15 15 12 1.983 2.645 120.7 10.3 20 19 15 48.9 –15 45 42 1.893 2.664 130.5 10.1 30 19 12 30.7 –16 27 44 1.818 2.682 140.9 9.9

Jun. 9 19 06 41.2 –17 20 49 1.762 2.701 152.0 9.8 19 18 58 47.3 –18 22 48 1.730 2.719 163.4 9.6 29 18 49 34.6 –19 30 10 1.724 2.737 174.5 9.4 Jul. 9 18 40 04.3 –20 38 40 1.745 2.756 172.0 9.5 19 18 31 18.0 –21 44 24 1.794 2.774 160.7 9.7

29 18 24 11.1 –22 44 45 1.869 2.792 149.5 10.0 Aug. 8 18 19 22.3 –23 38 25 1.967 2.810 138.8 10.2 18 18 17 09.7 –24 25 05 2.083 2.828 128.7 10.4

BAA Handbook 2020 Asteroids 51 ASTEROID OCCULTATIONS

OCCULTATIONS OF STARS BY ASTEROIDS AND DWARF PLANETS Favourable events predicted by Edwin Goffin:http://bedekkingen.vvs.be/predictions/asteroids2020/ One prediction is highlighted below. These represent reasonably good opportunities for UK observers (see page 53 for corresponding Chart). Max Star Asteroid Asteroid Star Date UT ΔM Duration Magnitude Diameter hh:mm s km 4 Vesta HIP 14439 Feb. 11 22:02 2.8 28s 5.2 522 Key for the table above: ΔM The change in V magnitude. Max Duration Duration of the occultation for an observer at the centre of the shadow path Star Magnitude Visual magnitude of the star

Featured TNO None selected

Regional predictions Events for region 3 (Europe) are listed using the criteria: Star Mag v11.0 and brighter, duration >3s, magnitude drop >1.0

TNO Global predictions The current Pro–Am predictions can be selected from the ERC Lucky Star project web site. http://lesia.obspm.fr/lucky–star/predictions.php

Major planets Mars and Venus are listed. There are no predictions for the gas giants.

Prediction uncertainties Errors are reduced now that the Gaia DR2 data are released. The main uncertainty is in the ephemeris of the object or where there is some undetected stellar multiplicity. Observers should continue to monitor outside the path to detect possible anomalies or satellites. Mobile observers could consider setting up in the track.

Event duration The maximum duration is for an observer in the centre of the shadow. The duration falls to zero at the shadow edge. Results are published on EURASTER.NET where Positive results are prioritised. http://www.euraster.net/results/index.html – where there is a link to the BEST results.

Recording and reporting an observation Observations should be timed with a UT accuracy of typically 0.1 to 0.3 sec and reported to the Asteroids and Remote Planets Section via Occultation Coordinator, Tim Haymes ([email protected]), where details will be checked and collated. Negative observations (no occultation) should also be reported. European observers are strongly encouraged to subscribe to the PLANOCCULT mailing list for last–minute updates and observation reports : – visit : http://vps.vvs.be/mailman/listinfo/planoccult and follow the instructions to use the list server.

For more up–to–date information on predictions, finder charts and occultation news, consult the following home pages : http://www.iota–es.de/ – International Occultation Timing Association http://www.lesia.obspm.fr/perso/bruno–sicardy/ – Bruno Sicardy http://asteroidoccultations.com/ – Steve Preston http://lesia.obspm.fr/lucky-star/results.php – European Research Council, Lucky Star Project

52 Asteroids BAA Handbook 2020 ASTEROID OCCULTATIONS 4 Vesta & FK6 2220 2020 feb 11 21h57.8m U.T.

Planet: a = 2.36, e = 0.09 Star: Source cat. GDR2a

V. mag. = 8.06 Diam. = 523.2 km = 0.29" α = 3h06m23.685s δ = +13°11'12.85" µ = 37.98"/h π = 3.59" Ref. = EG2018 Vmag = 5.32 Bmag = 5.90

∆m = 2.8 Max. dur. = 27.9s Sun : 85° Moon : 131° , 90%

21h52m00s − 22h03m00s; int. 1m

Vis. magn. scale

+14° 1

+13° 5 6 Declination (2000.0) 7

9 +12° 10

3h15 3h10 3h05 3h00 Right ascension (2000.0) BAAA20_02001.ps: Handbook 2019-01-30 2020 20:08:00 Asteroids 38 Edwin Goffin, Hoboken, Belgium 53 ASTEROID OCCULTATIONS REGIONAL PREDICTIONS EUROPE, AFRICA and MIDDLE EAST Minor Planet Diam Max. Mag. Date Time No. Name (IRAS) Star ID V Dur. drop RoV 2020 h m " sec. Jan. 2 22 17.5 1408 Trusanda 0.02 TYC 0239–00633–1 9.91 6.8 6.2 3 6 1 37.0 6 Hebe 0.09 TYC 0300–00301–1 10.38 10.3 1.2 3 14 15 47.1 127 Johanna 0.08 TYC 2434–01221–1 8.28 9.1 3.8 3 14 21 18.7 834 Burnhamia 0.03 TYC 1317–00893–1 10.52 4.8 4.6 3 16 3 20.4 407 Arachne 0.08 TYC 1372–01714–1 9.02 7.9 3.3 3 22 20 42.8 480 Hansa 0.05 TYC 4802–00276–1 9.64 6.0 2.7 3 Feb. 9 20 30.6 332 Siri 0.02 TYC 1247–00515–1 10.23 3.7 4.6 3 11 21 57.8 4 Vesta 0.29 HIP 14439 5.32 27.9 2.8 3 14 1 26.2 58 Concordia 0.06 UCAC4 398–057584 10.69 10.5 3.0 3 14 23 07.0 83 Beatrix 0.08 TYC 1945–00519–1 10.54 9.1 1.5 3 15 20 37.1 977 Philippa 0.04 TYC 2466–00499–1 9.36 7.9 5.1 3 17 1 15.3 582 Olympia 0.06 TYC 0259–01457–1 10.28 3.0 1.6 3 19 16 40.8 52 Europa 0.11 HIP 5647 8.44 7.6 3.8 3 22 17 20.8 511 Davida 0.25 TYC 1921–00794–1 10.57 76.3 0.7 3 27 18 25.8 46 Hestia 0.09 TYC 0830–00264–1 9.93 9.5 2.6 3 29 6 41.1 85 Io 0.10 TYC 6232–00016–1 10.29 7.6 2.5 3 Mar. 11 18 49.7 538 Friederike 0.04 TYC 0850–00681–1 10.83 5.1 3.7 3 13 19 49.2 43 Ariadne 0.05 TYC 1378–00014–1 9.91 17.5 2.2 3 16 3 28.5 449 Hamburga 0.05 TYC 6261–01305–1 9.25 5.4 5.4 3 16 17 29.4 253 Mathilde 0.03 UCAC4 533–025488 10.84 5.5 4.9 3 20 17 06.9 127 Johanna 0.06 TYC 2426–00511–1 10.45 6.3 2.8 3 20 17 12.3 601 Nerthus 0.03 TYC 0746–00233–1 9.72 6.2 5.9 3 21 18 36.5 230 Athamantis 0.09 TYC 0778–00121–1 10.89 20.4 1.1 3 Apr. 6 2 32.7 780 Armenia 0.05 TYC 0349–00494–1 11.00 8.2 3.3 3 8 0 38.9 183964 2004DJ71 0.01 TYC 1437–01897–1 10.06 7.1 12.6 3 13 23 28.7 585 Bilkis 0.06 TYC 5565–00056–1 10.93 6.8 2.5 3 22 4 50.3 322 Phaeo 0.05 TYC 6841–01470–1 10.19 29.5 3.8 3 May 2 20 00.5 347 Pariana 0.05 TYC 1907–00350–1 10.33 3.0 3.6 3 5 22 45.1 58 Concordia 0.08 TYC 4971–01020–1 10.87 10.1 1.8 3 15 23 20.0 468 Lina 0.04 HIP 81893 7.52 6.2 7.0 3 19 4 37.0 552 Sigelinde 0.04 TYC 5790–00218–1 10.03 5.8 4.9 3 Jun. 9 23 54.3 435 Ella 0.04 HIP 77369 10.43 4.3 3.4 3 Jul. 13 1 23.3 925 Alphonsina 0.03 TYC 1725–00707–1 10.59 4.0 3.1 3 16 4 28.1 266 Aline 0.06 TYC 1768–00553–1 9.22 3.9 4.6 3 28 21 20.5 126 Velleda 0.05 TYC 6910–01271–1 10.42 5.3 1.7 3 31 2 09.1 2235 Vittore 0.03 HIP 10330 9.02 3.6 7.5 3 Aug. 3 19 44.4 893 Leopoldina 0.06 TYC 5712–00330–1 10.73 6.6 3.1 3 7 2 00.0 640 Brambilla 0.04 TYC 1203–01269–1 10.33 13.8 4.3 3 9 21 58.1 2003QX111 0.01 HIP 6509 9.74 20.0 13.2 3 12 23 13.5 11 Parthenope 0.12 TYC 0631–00813–1 9.60 16.0 1.5 3 14 1 03.7 39 Laetitia 0.08 TYC 0711–00265–1 10.12 5.1 1.6 3 14 2 07.4 1042 Amazone 0.04 TYC 1249–00179–1 10.08 4.0 5.5 3 22 23 10.8 328 Gudrun 0.07 TYC 6947–00591–1 9.34 8.4 4.2 3 27 18 34.0 129 Antigone 0.09 Gaia 072–0606240 9.95 21.8 1.3 3 28 20 20.4 111 Ate 0.09 TYC 6861–01056–1 10.21 62.9 2.8 3 29 22 42.8 136 Austria 0.05 TYC 5725–01093–1 10.30 7.5 2.5 3 Sep. 4 1 43.3 522 Helga 0.04 TYC 1304–00811–1 9.89 5.6 5.5 3 9 0 15.4 52 Europa 0.13 TYC 1318–01031–1 9.23 10.8 2.7 3 9 19 53.7 56 Melete 0.09 TYC 5698–02641–1 9.39 7.6 2.5 3 21 0 17.3 39 Laetitia 0.09 TYC 0725–00276–1 9.16 8.7 2.2 3 27 18 34.7 336 Lacadiera 0.06 TYC 5736–01880–1 9.79 7.5 3.8 3 Oct. 4 2 22.0 406 Erna 0.04 HIP 15181 8.09 13.0 6.2 3 6 2 18.0 943 Begonia 0.04 TYC 1330–01299–1 10.81 4.1 4.0 3 12 0 20.3 245 Vera 0.05 TYC 1900–00992–1 8.59 5.5 4.4 3 24 20 28.3 1171 Rusthawelia 0.06 HIP 5315 6.20 8.0 7.4 3 Nov. 1 18 49.3 829 Academia 0.05 TYC 1757–00993–1 10.95 4.5 2.7 3 4 0 01.8 11 Parthenope 0.16 TYC 0033–01170–1 9.87 17.5 0.6 3 10 0 21.0 866 Fatme 0.06 UCAC4 532–009158 10.98 8.3 2.9 3 10 21 21.6 683 Lanzia 0.06 TYC 1729–01829–1 8.97 10.1 4.4 3 54 Asteroids BAA Handbook 2020 ASTEROID OCCULTATIONS cont'd

Minor Planet Diam Max. Mag. Date Time No. Name (IRAS) Star ID V Dur. drop RoV 2020 h m " sec.

16 5 47.1 171 Ophelia 0.08 TYC 1308–01881–1 9.60 12.8 3.4 3 19 4 57.3 234 Barbara 0.04 TYC 0151–00841–1 10.01 6.9 3.0 3 22 22 34.9 147 Protogeneia 0.07 TYC 5238–01366–1 10.55 13.6 3.3 3 24 19 29.4 283 Emma 0.11 TYC 2392–01288–1 8.62 12.9 4.3 3 27 21 28.7 1167 Dubiago 0.04 TYC 1305–00959–1 10.78 5.0 4.4 3 29 0 39.4 416 Vaticana 0.05 TYC 1965–00114–1 10.11 10.7 3.3 3 Dec. 1 23 59.0 140 Siwa 0.05 TYC 0834–01465–1 9.59 19.5 4.6 3 4 3 07.7 522 Helga 0.06 TYC 1304–01027–1 9.89 8.2 4.3 3 9 5 20.5 498 Tokio 0.04 TYC 0865–01220–1 9.50 4.3 5.5 3 9 20 42.0 250 Bettina 0.07 UCAC4 631–016671 10.13 7.6 1.7 3 11 15 03.0 257 Silesia 0.04 TYC 5249–01053–1 9.49 4.1 5.5 3 17 19 42.9 1237 Genevieve 0.03 TYC 2457–00828–1 9.47 4.0 5.1 3 18 20 54.1 401 Ottilia 0.05 TYC 0628–00328–1 10.36 76.2 4.3 3 20 1 29.4 627 Charis 0.02 TYC 0275–01077–1 9.87 3.7 5.7 3 23 23 12.3 130 Elektra 0.13 TYC 4801–04107–1 8.31 14.6 3.2 3 24 6 44.7 356 Liguria 0.16 HIP 33528 9.80 17.9 1.3 3 26 22 11.7 203 Pompeja 0.10 Gaia 119–0059621 10.95 11.3 1.9 3 27 20 47.9 748 Simeisa 0.06 TYC 1260–01120–1 10.24 16.8 3.9 3 30 3 58.9 247 Eukrate 0.09 TYC 1442–01176–1 10.15 24.2 2.8 3

MAJOR PLANET PREDICTIONS Planet Max. Date Time Name Diam Star ID V Dur. RoV 2020 h m " sec.

Feb. 11 8 48.8 Venus 16.36 HIP 1169 6.90 335.8 7 Apr. 14 9 29.7 Mars 6.91 TYC 6352–00344–1 9.62 238.6 2 May 4 7 25.5 Mars 7.78 HIP 107478 8.99 271.3 2 Jun. 8 17 30.3 Mars 9.78 TYC 5249–00975–1 8.25 359.8 8 Jun. 29 19 14,0 Mars 11.35 HIP 635 6.40 453.9 7 Sep. 10 8 01.5 Mars 20.29 TYC 0035–00187–1 9.87 49131.8 1, 2 Oct. 6 3 35.3 Mars 22.58 TYC 0034–00902–1 9.67 1753.6 2

On September 10th 8h UT, Mars occults TYC 0035–00187–1 while the planet passes a stationary point. The occultation is observable from the North and South American continents. Filters may be required to aid detection. There are no predictions for the gas giants.

Using the tables In the table of predictions : Time = UT of closest geocentric approach.

Region of Visibility codes (RoV): 1 = North and Central America 2 = South America 3 = Europe, N. Africa and the Middle East 4 = South Africa 5 = Russia 6 = Pakistan, India, and SE Asia 7 = Japan, China and Taiwan 8 = Australia and New Zealand

Where diameters are not listed in the IRAS catalogue, an assumed value of A, the geometric albedo, has been used to calculate a value for the asteroid diameter. Predictions computed by Edwin Goffin. Track details are available from the Flemish Astronomical Association ftp site: http://bedekkingen.vvs.be/predictions/asteroids2020/Occ20R03.pdf

BAA Handbook 2020 Asteroids 55 ASTEROIDS: FAVOURABLE OBSERVING OPPORTUNITIES

LIGHTCURVE OPPORTUNITIES

Based on an analysis of both numbered and unnumbered objects in the Minor Planet Center MPCORB database by Brian D. Warner. Asteroids are listed which at opposition reach magnitude 14.5 or brighter, and for which the rotation period is very uncertain or unknown. Where a 'U' code is given as '1' or ‘1+’, the values given are based on fragmentary lightcurves and are likely to be incorrect. Period/amplitude data are taken from the list maintained by Brian D. Warner, Alan W. Harris of the Space Science Institute and Petr Pravec of the Astronomical Institute, Ondrejov, Czech Republic, at:

http://www.minorplanet.info/lightcurvedatabase.html

The chart below shows the path of asteroid 21242 (1995 WZ41) plotted 30 days either side of opposition. This object's rotation period is not known. Furthermore, it passes through a minimum phase angle of 0.20º on November 18.8, attaining magnitude ~14.2, and so is a good target for photometric observation.

Chart prepared using GUIDE 8.0. 56 Asteroids BAA Handbook 2020 ASTEROIDS: FAVOURABLE OBSERVING OPPORTUNITIES Asteroid Opposition Amplitude Number Name Date V Δ Dec. U Period of Magnitude Variation m d au ° Code h 1549 Mikko 02 02.2 14.5 1.102 +24 1+ 11.49 0.03 163373 2002 PZ39 # 02 12.0 14.3* 0.049 +29 1415 Malautra 03 11.2 14.1 1.076 +1 1 >12. 0.03 1247 Memoria 05 07.2 14.4 1.889 –14 438908 2009 XO # 05 09.5 14.3* 0.027 –10

37152 2000 VV56 05 12.8 14.3 0.695 –27 2171 Kiev 05 17.3 14.5 0.968 –8 1594 Danjon 05 21.6 13.3 0.934 –17 1 >12. 0.03 1367 Nongoma 05 26.4 14.4 1.074 –41 1+ 94.8 0.3–0.83 3459 Bodil 05 28.7 14.5 0.965 –16

3796 Lene 06 27.9 14.5 1.278 –22 242450 2004 QY2 # 07 01.8 14.2* 0.190 –11 0.83 957 Camelia 07 25.4 14.5 2.160 0 1+ 150 0.3 33881 2000 JK66 07 28.2 14.5 0.626 –20 2168 Swope 08 06.8 14.4 1.064 –16

2532 Sutton 08 20.6 14.5 0.983 –15 1 51.362 0.02 2236 Austrasia 08 31.7 13.8 0.874 –18 2680 Mateo 09 03.1 14.3 0.879 –9 58143 1983 VD7 09 08.4 14.4 0.853 –26 5687 Yamamotoshinobu 09 08.6 14.4 1.530 –17

1937 Locarno 09 10.5 14.1 1.125 –25 6792 Akiyamatakashi 09 24.0 14.2 0.798 –7 2299 Hanko 09 29.1 14.3 0.864 0 1024 Hale 10 04.3 13.6 1.273 –16 1+ 16 0.1 2819 Ensor** 10 05.0 14.1 1.207 +4

842 Kerstin 10 05.9 14.4 1.871 +8 21182 1994 EC2 10 09.0 14.5 0.781 +9 2913 Horta 10 18.6 14.5 1.217 +7 2409 Chapman 10 25.6 14.3 0.930 +6 4103 Chahine 10 28.4 13.5 1.056 +29 0.35

21242 1995 WZ41** 11 18.8 14.1 0.748 +20 8823 1987 WS3 11 29.4 14.3 0.986 +20 1934 Jeffers 11 29.8 13.9 0.830 +4 153201 2000 WO107 # 12 01.1 13.2* 0.039 +25 2831 Stevin** 12 14.1 14.5 1.136 +23

795 Fini 12 18.7 14.2 1.955 +50 1+ 9.292 0.02–0.06

* When brightest, **Low phase angle target, # Near–Earth asteroid

BAA Handbook 2020 Asteroids 57 ASTEROIDS: FAVOURABLE OBSERVING OPPORTUNITIES OPPORTUNITIES AT LOW PHASE ANGLE AND AT OPPOSITION Asteroids have been selected on the following criteria: V≤14.5, Phase Angle ≤0.20° Asteroid Opposition Minimum Maximum Number Name Date Phase Angle V Dec. Period Lightcurve Amplitude m d ° ° h mag 389 Industria 01 02.3 0.10 11.0 +23 8.53 0.34 1196 Sheba 01 02.9 0.17 13.5 +23 6.319 0.28 1010 Marlene 01 04.9 0.18 14.4 +23 31.06 0.32 537 Pauly 01 21.1 0.01 13.9 +20 16.168 0.20 602 Marianna 02 22.2 0.15 13.1 +10 35.195 0.17 582 Olympia 02 25.2 0.10 11.2 +9 36.312 0.60 839 Valborg 02 27.9 0.04 14.5 +8 10.366 0.19 184 Dejopeja 03 06.4 0.14 12.2 +5 6.4416 0.30 358 Apollonia 03 08.8 0.12 13.0 +4 50.6 0.15 122 Gerda 03 09.8 0.12 12.1 +4 10.685 0.26 1225 Ariane 03 28.8 0.19 14.1 –3 5.5068 0.36 300 Geraldina 03 31.1 0.16 14.4 –4 6.8423 0.32 24 Themis 04 26.2 0.00 11.0 –14 8.374 0.14 673 Edda 05 11.8 0.12 13.8 –18 22.34 0.21 1499 Pori 05 19.4 0.15 14.2 –20 3.3557 0.34 468 Lina 05 30.9 0.15 14.1 –22 16.33 0.18 449 Hamburga 06 14.8 0.06 13.0 –23 18.263 0.17 1336 Zeelandia 07 04.3 0.18 14.0 –23 15.602 0.61 551 Ortrud 07 12.2 0.18 13.9 –22 17.416 0.19 554 Peraga 07 15.7 0.07 12.3 –22 13.713 0.28 846 Lipperta 07 18.0 0.07 14.3 –21 1641 0.30 44 Nysa 08 05.8 0.08 10.5 –17 6.422 0.52 2168 Swope 08 06.8 0.02 14.4 –16 573 Recha 09 06.3 0.13 12.8 –6 7.1663 0.34 1576 Fabiola 09 27.9 0.17 14.5 +2 6.889 0.26 2534 Houzeau 10 02.9 0.19 14.5 +3 53.237 0.22 1059 Mussorgskia 10 15.0 0.17 14.0 +8 5.636 0.21 189 Phthia 10 18.2 0.11 11.9 +9 22.346 0.28 859 Bouzareah 10 27.5 0.18 13.5 +12 23.2 0.13 401 Ottilia 10 29.8 0.02 13.6 +14 6.049 0.24 1578 Kirkwood 11 09.6 0.17 14.3 +16 12.518 0.22 21242 1995 WZ41 11 18.8 0.20 14.2 +20 266 Aline 11 19.0 0.18 11.5 +19 13.018 0.10 838 Seraphina 11 22.2 0.02 13.4 +20 15.67 0.30 2617 Jiangxi 12 6.0 0.13 13.0 +23 11.774 0.57 2831 Stevin 12 14.2 0.03 14.5 +23

58 Asteroids BAA Handbook 2020 NEO CLOSE APPROACHES TO EARTH Prepared from data on the Jet Propulsion Laboratory's Near Earth Object Program website at: http://neo.jpl.nasa.gov/ca/ This lists asteroids predicted to pass within 0.05 au (about 7.5 million km) of the Earth attaining magnitude 19.5 or brighter during 2020 (as of 2019 Apr 30). Especially favourable approaches are shown in bold. Newly–discovered objects may be added to the list available via the JPL NEO site, so do check this for recent updates. The Nominal Miss Distance is given in Lunar Distances (LD) and Astronomical Units (au). The apparent Elongation and Declination are geocentric. Ephemerides should be obtained near the time of observation from the MPC via its Minor Planet and Comet Ephemeris Service at: http://www.minorplanetcenter.net/iau/MPEph/MPEph.html For your local ephemerides, choose a location or observatory near your site. Note that the positions of some objects may be subject to significant uncertainty.

Object Close Nominal Relative Magnitude Date Elongation Declination Approach Miss Distance Velocity H (brightest) when when when Date* brightest brightest brightest LD** au km s–1 ° ° 2009 BH2 Jan. 18.6 14.59 0.0375 17.94 22.4 18.6 Jan. 21 93 +17 2013 DU Jan. 20 15.26 0.0392 6.39 23.9 18.7 Jan. 18 131 –22 163373 Feb. 15.5 15.02 0.0386 15.19 18.9 14.3 Feb. 12 127 +29 2018 CW2 Feb. 17 5.97 0.0154 10.22 25.5 18.1 Feb. 16 144 +47 2015 BK509 Feb. 28 18.26 0.0469 12.52 22.4 17.9 Feb. 24 135 +23 2017 BM123 Mar 1.5 10.43 0.0268 8.14 23.7 17.5 Feb. 26 155 +34 2018 GY Mar. 15 6.20 0.0159 9.51 24.8 16.6 Mar. 17 176 +2 2012 XA133 Mar. 27.2 17.33 0.0445 23.67 20.9 16.8 Mar. 24 117 –63 2006 FH36 Mar. 30.2 11.25 0.0289 5.06 22.9 17.6 Apr. 5 126 –55 2015 FC35 Apr. 4.4 10.41 0.0268 13.84 21.9 15.8 Apr. 2 144 –32 363599 Apr. 11.7 19.15 0.0492 24.49 21.0 17.1 Apr. 9 117 +37 52768 Apr. 29.4 16.36 0.0421 8.70 15.8 10.8 May 1 133 –34 438908 May 7.5 8.83 0.0227 12.78 20.5 14.3 May 9 138 –7 2016 HP6 May 7.9 4.33 0.0111 5.72 25.3 16.9 May 7 149 +2 388945 May 10.6 7.27 0.0187 8.78 20.4 13.8 May 8 132 –29 2000 KA May 12.5 8.84 0.0227 13.50 21.7 15.6 May 14 138 +23 136795 May 21.9 16.02 0.0412 11.68 18.1 14.6 May 26 96 –69 163348 Jun. 6.1 13.25 0.0341 11.15 20.1 14.4 Jun. 10 161 –21 2013 XA22 Jun. 9 10.55 0.0271 6.47 22.8 17.5 Jun. 3 128 +2 2017 MF7 Jun. 14 3.68 0.0095 10.92 25.9 19.0 Jun. 15 102 +0 441987 Jun. 24.3 9.78 0.0251 12.89 21.5 16.8 Jun.27 101 +34 2002 BF25 Jul. 21.1 9.38 0.0241 6.81 22.2 17.3 Jul. 15 108 –70 2009 PQ1 Aug. 5 10.71 0.0275 13.47 22.5 17.0 Aug, 8 130 –30 2011 ES4 Sep. 1 0.21 0.0005 8.35 25.7 11.3 Sep. 1 146 –30 465824 Sep. 6.3 19.28 0.0496 14.04 21.7 18.1 Sep. 2 104 +37 2014 QJ33 Sep. 18 11.43 0.0294 8.28 23.7 18.4 Sep. 13 133 –13 2017 SL16 Sep. 20.3 8.84 0.0227 6.40 25.8 19.0 Sep. 24 158 +13 2017 UH5 Oct. 20 8.89 0.0228 5.93 26.5 19.3 Oct. 22 164 +8 2017 WJ16 Nov. 23 4.95 0.0127 4.75 24.3 16.2 Nov. 24 148 +48 153201 Nov. 29.2 11.19 0.0288 25.07 19.3 13.2 Nov. 30 161 +25 2017 XQ60 Dec. 21 12.47 0.0321 15.68 24.4 19.1 Dec. 20 119 –2 2011 CL50 Dec. 24 3.07 0.0079 3.36 27.6 18.5 Dec. 26 157 +42 501647 Dec. 25.8 7.86 0.0202 10.01 22.3 16.4 Dec. 23 119 +74 2012 XE133 Dec. 27 11.66 0.0300 9.16 23.4 17.3 Dec. 25 145 +53 2012 UK171 Dec. 30.1 15.45 0.0397 4.71 24.4 18.4 Dec. 23 169 +13

* Dates are quoted to the nearest day if uncertainty in close approach date is greater than ±0.2 day ** Lunar Distance: 1.0 LD = 3.844 x 105 km or 0.00257 AU. BAA Handbook 2020 Asteroids 59 JUPITER

Opposition: July 14 Conjunction: –

2020 Equat Polar RA Dec. Mag D Δ Diam. Diam. E h m º ' " " º au Jan. 2 18 30.0 –23 10 –1.8 31.8 29.7 –2.0 6.207 12 18 40.0 –23 03 –1.8 31.9 29.8 –2.0 6.181 22 18 49.8 –22 53 –1.9 32.1 30.1 –1.9 6.134 Feb. 1 18 59.4 –22 42 –1.9 32.5 30.4 –1.8 6.067 11 19 08.5 –22 29 –1.9 33.0 30.8 –1.8 5.980 21 19 17.3 –22 14 –1.9 33.6 31.4 –1.7 5.875 Mar. 2 19 25.4 –21 60 –2.0 34.3 32.0 –1.6 5.754 12 19 32.8 –21 45 –2.0 35.1 32.8 –1.6 5.620 22 19 39.5 –21 31 –2.1 36.0 33.7 –1.5 5.475 Apr. 1 19 45.3 –21 18 –2.1 37.1 34.6 –1.5 5.321 11 19 50.0 –21 07 –2.2 38.2 35.7 –1.4 5.162 21 19 53.7 –20 59 –2.3 39.4 36.9 –1.4 5.002 May 1 19 56.1 –20 54 –2.3 40.7 38.1 –1.3 4.844 11 19 57.2 –20 52 –2.4 42.0 39.3 –1.3 4.693 21 19 57.1 –20 54 –2.5 43.3 40.5 –1.3 4.551 31 19 55.6 –20 60 –2.6 44.6 41.7 –1.2 4.425 Jun. 10 19 52.9 –21 09 –2.6 45.7 42.7 –1.2 4.318 20 19 49.0 –21 21 –2.7 46.6 43.6 –1.2 4.233 30 19 44.3 –21 34 –2.7 47.2 44.2 –1.2 4.174 Jul. 10 19 39.1 –21 48 –2.7 47.6 44.5 –1.2 4.144 20 19 33.6 –22 02 –2.7 47.6 44.5 –1.3 4.142 30 19 28.4 –22 15 –2.7 47.3 44.2 –1.3 4.171 Aug. 9 19 23.7 –22 26 –2.7 46.6 43.6 –1.3 4.227 19 19 19.9 –22 34 –2.6 45.8 42.8 –1.3 4.309 29 19 17.2 –22 40 –2.6 44.7 41.8 –1.3 4.413 Sep. 8 19 15.9 –22 43 –2.5 43.5 40.7 –1.3 4.535 18 19 15.9 –22 43 –2.4 42.2 39.5 –1.3 4.672 28 19 17.2 –22 41 –2.4 40.9 38.3 –1.3 4.819 Oct. 8 19 20.0 –22 36 –2.3 39.7 37.1 –1.2 4.971 18 19 23.9 –22 29 –2.2 38.5 36.0 –1.2 5.125 28 19 29.0 –22 19 –2.2 37.4 34.9 –1.2 5.276 Nov. 7 19 35.1 –22 06 –2.1 36.4 34.0 –1.1 5.422 17 19 42.0 –21 50 –2.1 35.5 33.2 –1.1 5.558 27 19 49.7 –21 31 –2.0 34.7 32.4 –1.0 5.683 Dec. 7 19 58.0 –21 09 –2.0 34.0 31.8 –1.0 5.793 17 20 06.8 –20 44 –2.0 33.5 31.3 –0.9 5.887 27 20 16.0 –20 16 –2.0 33.1 30.9 –0.8 5.963 37 20 25.5 –19 45 –1.9 32.8 30.6 –0.7 6.020

Description of the headings in the table can be found on page 22. 60 Jupiter BAA Handbook 2020 LONGITUDE OF CENTRAL MERIDIAN OF JUPITER SYSTEM I Day Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. º º º º º º º º º º º º 1 238.7 87.3 342.0 194.4 251.2 108.5 169.5 28.2 244.3 298.9 148.3 198.2 2 36.4 245.0 139.8 352.2 49.2 266.5 327.5 186.2 42.1 96.6 305.9 355.8 3 194.0 42.8 297.6 150.1 207.1 64.5 125.6 344.2 200.0 254.4 103.6 153.5 4 351.7 200.5 95.4 307.9 5.0 222.5 283.6 142.2 357.9 52.1 261.3 311.1 5 149.4 358.2 253.2 105.8 163.0 20.6 81.6 300.2 155.7 209.9 59.0 108.7 6 307.1 155.9 51.0 263.7 320.9 178.6 239.7 98.1 313.6 7.7 216.7 266.4 7 104.8 313.7 208.8 61.5 118.9 336.6 37.7 256.1 111.5 165.4 14.3 64.0 8 262.4 111.4 6.6 219.4 276.8 134.6 195.8 54.1 269.3 323.2 172.0 221.7 9 60.1 269.1 164.4 17.3 74.8 292.7 353.8 212.0 67.2 120.9 329.7 19.3 10 217.8 66.9 322.2 175.2 232.8 90.7 151.8 10.0 225.0 278.6 127.4 177.0 11 15.5 224.6 120.0 333.0 30.7 248.7 309.9 168.0 22.8 76.4 285.0 334.6 12 173.2 22.4 277.8 130.9 188.7 46.7 107.9 325.9 180.7 234.1 82.7 132.2 13 330.9 180.1 75.6 288.8 346.7 204.8 265.9 123.9 338.5 31.8 240.4 289.9 14 128.6 337.8 233.4 86.7 144.6 2.8 64.0 281.8 136.3 189.6 38.0 87.5 15 286.3 135.6 31.2 244.6 302.6 160.8 222.0 79.8 294.2 347.3 195.7 245.2 16 84.0 293.3 189.0 42.5 100.6 318.9 20.0 237.7 92.0 145.0 353.4 42.8 17 241.7 91.1 346.8 200.4 258.6 116.9 178.1 35.7 249.8 302.7 151.0 200.5 18 39.4 248.8 144.6 358.3 56.5 275.0 336.1 193.6 47.6 100.5 308.7 358.1 19 197.1 46.6 302.5 156.2 214.5 73.0 134.1 351.5 205.4 258.2 106.3 155.7 20 354.8 204.4 100.3 314.1 12.5 231.0 292.1 149.4 3.2 55.9 264.0 313.4 21 152.5 2.1 258.1 112.0 170.5 29.1 90.2 307.4 161.0 213.6 61.6 111.0 22 310.2 159.9 55.9 269.9 328.5 187.1 248.2 105.3 318.8 11.3 219.3 268.7 23 107.9 317.6 213.8 67.8 126.5 345.1 46.2 263.2 116.6 169.0 17.0 66.3 24 265.6 115.4 11.6 225.7 284.5 143.2 204.2 61.1 274.4 326.7 174.6 223.9 25 63.3 273.2 169.4 23.7 82.5 301.2 2.2 219.0 72.2 124.4 332.3 21.6 26 221.0 70.9 327.3 181.6 240.5 99.3 160.2 16.9 230.0 282.1 129.9 179.2 27 18.7 228.7 125.1 339.5 38.5 257.3 318.2 174.8 27.8 79.8 287.6 336.9 28 176.4 26.5 283.0 137.4 196.5 55.4 116.2 332.7 185.6 237.5 85.2 134.5 29 334.1 184.3 80.8 295.4 354.5 213.4 274.2 130.6 343.3 35.2 242.9 292.2 30 131.9 238.7 93.3 152.5 11.4 72.2 288.5 141.1 192.9 40.5 89.8 31 289.6 36.5 310.5 230.2 86.4 350.6 247.4

CHANGE OF LONGITUDE IN INTERVALS OF MEAN TIME

h º h º º m º m m º 1 36.58 7 256.05 10 6.10 1 0.61 6 3.66 2 73.16 8 292.63 20 12.19 2 1.22 7 4.27 3 109.74 9 329.21 30 18.29 3 1.83 8 4.88 4 146.32 10 365.79 40 24.39 4 2.44 9 5.49 5 182.90 11 402.37 50 30.48 5 3.05 10 6.10 6 219.48 12 438.95 60 36.58 System I applies to all objects situated on or between the north component of the South Equatorial Belt and the south component of the North Equatorial Belt.

BAA Handbook 2020 Jupiter 61 LONGITUDE OF CENTRAL MERIDIAN OF JUPITER SYSTEM II Day Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. º º º º º º º º º º º º 1 281.8 253.9 287.4 263.1 91.1 71.8 263.9 246.1 225.6 51.3 24.2 205.2 2 71.9 44.0 77.5 53.3 241.4 222.2 54.3 36.4 15.8 201.5 174.3 355.2 3 221.9 194.1 227.7 203.6 31.7 12.6 204.7 186.8 166.1 351.6 324.3 145.3 4 12.0 344.2 17.8 353.8 182.0 162.9 355.1 337.1 316.3 141.7 114.4 295.3 5 162.0 134.3 168.0 144.0 332.3 313.3 145.5 127.5 106.6 291.8 264.4 85.3 6 312.1 284.4 318.1 294.3 122.6 103.7 295.9 277.8 256.8 82.0 54.5 235.3 7 102.1 74.5 108.3 84.5 273.0 254.1 86.3 68.2 47.0 232.1 204.5 25.3 8 252.2 224.6 258.5 234.8 63.3 44.5 236.7 218.5 197.2 22.2 354.6 175.3 9 42.2 14.7 48.6 25.0 213.6 194.9 27.1 8.9 347.5 172.3 144.6 325.3 10 192.3 164.8 198.8 175.3 3.9 345.3 177.6 159.2 137.7 322.4 294.6 115.4 11 342.3 314.9 349.0 325.5 154.3 135.7 328.0 309.5 287.9 112.5 84.7 265.4 12 132.4 105.0 139.1 115.8 304.6 286.1 118.4 99.8 78.1 262.6 234.7 55.4 13 282.5 255.1 289.3 266.0 94.9 76.5 268.8 250.2 228.3 52.7 24.8 205.4 14 72.5 45.2 79.5 56.3 245.3 226.9 59.2 40.5 18.5 202.8 174.8 355.4 15 222.6 195.4 229.7 206.5 35.6 17.3 209.6 190.8 168.7 352.9 324.8 145.4 16 12.6 345.5 19.9 356.8 186.0 167.7 0.0 341.1 318.9 143.0 114.9 295.4 17 162.7 135.6 170.0 147.1 336.3 318.1 150.4 131.4 109.1 293.1 264.9 85.4 18 312.8 285.7 320.2 297.3 126.7 108.5 300.8 281.7 259.3 83.2 54.9 235.5 19 102.9 75.8 110.4 87.6 277.0 258.9 91.2 72.0 49.4 233.3 204.9 25.5 20 252.9 226.0 260.6 237.9 67.4 49.3 241.5 222.3 199.6 23.4 355.0 175.5 21 43.0 16.1 50.8 28.1 217.7 199.8 31.9 12.6 349.8 173.5 145.0 325.5 22 193.1 166.2 201.0 178.4 8.1 350.2 182.3 162.9 140.0 323.5 295.0 115.5 23 343.1 316.4 351.2 328.7 158.4 140.6 332.7 313.2 290.1 113.6 85.1 265.5 24 133.2 106.5 141.4 119.0 308.8 291.0 123.1 103.5 80.3 263.7 235.1 55.5 25 283.3 256.6 291.6 269.3 99.2 81.4 273.5 253.8 230.4 53.8 25.1 205.5 26 73.4 46.8 81.8 59.6 249.5 231.8 63.9 44.0 20.6 203.8 175.1 355.6 27 223.5 196.9 232.0 209.9 39.9 22.2 214.2 194.3 170.7 353.9 325.1 145.6 28 13.5 347.1 22.2 0.2 190.3 172.6 4.6 344.6 320.9 144.0 115.2 295.6 29 163.6 137.2 172.5 150.5 340.7 323.0 155.0 134.8 111.0 294.0 265.2 85.6 30 313.7 322.7 300.8 131.0 113.5 305.3 285.1 261.2 84.1 55.2 235.6 31 103.8 112.9 281.4 95.7 75.3 234.1 25.6 CHANGE OF LONGITUDE IN INTERVALS OF MEAN TIME

h º h º m º m º m º 1 36.26 7 253.83 10 6.04 1 0.60 6 3.63 2 72.52 8 290.09 20 12.09 2 1.21 7 4.23 3 108.78 9 326.35 30 18.13 3 1.81 8 4.83 4 145.05 10 362.61 40 24.17 4 2.42 9 5.44 5 181.31 11 398.87 50 30.22 5 3.02 10 6.04 6 217.57 12 435.14 60 36.26 System II applies to all objects situated north of the south component of the North Equatorial Belt or south of the north component of the South Equatorial Belt. 62 Jupiter BAA Handbook 2020 LONGITUDE OF CENTRAL MERIDIAN OF JUPITER SYSTEM III (2009) Day Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. º º º º º º º º º º º º 1 306.5 286.8 328.0 312.0 147.9 136.9 336.9 327.4 315.1 148.8 130.0 319.0 2 96.8 77.1 118.4 102.5 298.5 287.5 127.6 118.0 105.7 299.2 280.3 109.3 3 247.1 227.5 268.8 253.0 89.0 78.2 278.3 268.6 256.2 89.6 70.6 259.5 4 37.4 17.9 59.2 43.5 239.6 228.8 69.0 59.2 46.7 240.0 220.9 49.8 5 187.7 168.2 209.6 194.0 30.2 19.5 219.6 209.8 197.2 30.4 11.2 200.1 6 338.0 318.6 0.1 344.5 180.8 170.1 10.3 0.5 347.7 180.8 161.6 350.4 7 128.3 109.0 150.5 135.0 331.4 320.8 161.0 151.1 138.2 331.2 311.9 140.7 8 278.7 259.3 300.9 285.5 122.0 111.4 311.7 301.7 288.6 121.6 102.2 290.9 9 69.0 49.7 91.4 76.0 272.6 262.1 102.3 92.3 79.1 272.0 252.5 81.2 10 219.3 200.1 241.8 226.5 63.2 52.8 253.0 242.9 229.6 62.3 42.8 231.5 11 9.6 350.5 32.2 17.0 213.7 203.4 43.7 33.5 20.1 212.7 193.1 21.8 12 160.0 140.8 182.7 167.5 4.3 354.1 194.3 184.1 170.6 3.1 343.4 172.1 13 310.3 291.2 333.1 318.0 155.0 144.8 345.0 334.7 321.0 153.5 133.7 322.3 14 100.6 81.6 123.6 108.6 305.6 295.4 135.7 125.2 111.5 303.8 284.0 112.6 15 250.9 232.0 274.0 259.1 96.2 86.1 286.3 275.8 262.0 94.2 74.3 262.9 16 41.3 22.4 64.4 49.6 246.8 236.8 77.0 66.4 52.4 244.5 224.6 53.2 17 191.6 172.7 214.9 200.2 37.4 27.4 227.7 217.0 202.9 34.9 14.9 203.4 18 341.9 323.1 5.4 350.7 188.0 178.1 18.3 7.6 353.3 185.3 165.2 353.7 19 132.3 113.5 155.8 141.2 338.6 328.8 169.0 158.1 143.8 335.6 315.5 144.0 20 282.6 263.9 306.3 291.8 129.2 119.5 319.7 308.7 294.2 126.0 105.8 294.3 21 73.0 54.3 96.7 82.3 279.9 270.1 110.3 99.2 84.6 276.3 256.1 84.6 22 223.3 204.7 247.2 232.9 70.5 60.8 261.0 249.8 235.1 66.6 46.4 234.8 23 13.6 355.1 37.7 23.4 221.1 211.5 51.6 40.4 25.5 217.0 196.7 25.1 24 164.0 145.5 188.1 174.0 11.7 2.2 202.3 190.9 175.9 7.3 347.0 175.4 25 314.3 295.9 338.6 324.5 162.4 152.9 352.9 341.4 326.4 157.7 137.3 325.7 26 104.7 86.3 129.1 115.1 313.0 303.5 143.6 132.0 116.8 308.0 287.5 115.9 27 255.0 236.7 279.5 265.6 103.7 94.2 294.2 282.5 267.2 98.3 77.8 266.2 28 45.4 27.1 70.0 56.2 254.3 244.9 84.8 73.1 57.6 248.7 228.1 56.5 29 195.7 177.5 220.5 206.8 44.9 35.6 235.5 223.6 208.0 39.0 18.4 206.8 30 346.1 11.0 357.3 195.6 186.2 26.1 14.1 358.4 189.3 168.7 357.1 31 136.4 161.5 346.2 176.7 164.6 339.6 147.3

CHANGE OF LONGITUDE IN INTERVALS OF MEAN TIME h º h º m º m º m º 1 36.27 7 253.91 10 6.05 1 0.60 6 3.63 2 72.54 8 290.18 20 12.09 2 1.21 7 4.23 3 108.82 9 326.45 30 18.14 3 1.81 8 4.84 4 145.09 10 362.72 40 24.18 4 2.42 9 5.44 5 181.36 11 399.00 50 30.23 5 3.02 10 6.05 6 217.63 12 435.27 60 36.27 System III applies to the origin of radio emissions from the planet. See page 64 for a description. BAA Handbook 2020 Jupiter 63 LONGITUDE OF CENTRAL MERIDIAN OF JUPITER SYSTEM III – DEFINITION Radio radiation from Jupiter at around 20MHz was discovered in 1955. It varies with the rotation of the planet and this is known as "System III". It is of interest because it indicates rotation beneath the cloud cover. Radio radiation emanates from the magnetosphere of Jupiter, and the rotation is due to the fact that the magnetic poles are not situated exactly at the poles of rotation. (The position of the satellite Io and the DE value are also significant for predicting "radio storms" from Jupiter.) In 1976 the IAU adopted a rotation for System III of 870.536 degrees per day. More recent work suggested an improvement to 870.536642, adopted in 2000 and used in recent BAA Handbooks. However subsequent analysis of data from Galileo gives a different value, consistent with 870.536 and its implied accuracy but not with 870.536642. The IAU provisionally recommends that 870.536 be used.

SATELLITES OF JUPITER

The satellites move from east to west across the face of the planet, and from west to east behind it. After conjunction with the Sun and before opposition, the shadow of Jupiter falls to the west, eclipse precedes occultation, and shadow–transit precedes transit. After opposition, the order of phenomena is reversed, occultation preceding eclipse and transit preceding shadow–transit.

Both phases of eclipse (EcD and EcR) and of occultation (OcD and OcR) of satellites III and IV may be seen if not too near opposition. Satellite I is much closer to the planet, and eclipse and occultation merge into one, OcD being followed by EcR after opposition and before conjunction, while EcD is followed by OcR after conjunction and before opposition. Satellite II normally behaves in the same manner but on rare occasions the separate phenomena of II may be observed. This happens when the planet is near quadrature and is tilted at almost the maximum amount.

On a few occasions all three of the inner satellites may be involved simultaneously in these phenomena. The motions of these three satellites are related in such a way that it is impossible for all three to undergo the same phenomenon at the same time.

The Institut de Mécanique Céleste et de Calcul des Ephémérides supplies event timings in Terrestrial Time (TT). These have been converted to Universal Time (UT), closely, by subtracting one minute (see tables on p.67–76), since ΔT is just over one minute now. The times of phenomena are given for the centre of the satellite. The light of the satellite will therefore begin to fade before the times given here, and observation should commence several minutes before the predicted times.

Charts are included for all 12 months of the year, although Jupiter will be too close to the Sun to be observable during January.

For all charts the satellites are labelled: I Io II Europa III Ganymede IV Callisto

64 Satellites of Jupiter BAA Handbook 2020 March February CONFIGURATION OF SATELLITES I – IV – I SATELLITES OF CONFIGURATION SATELLITES OF 2020 JUPITER OF SATELLITES January BAA Handbook 2020 Satellites of Jupiter 65 June May CONFIGURATION OF SATELLITES I – IV – I SATELLITES OF CONFIGURATION SATELLITES OF 2020 JUPITER OF SATELLITES April 66 Satellites of Jupiter BAA Handbook 2020 September August CONFIGURATION OF SATELLITES I – IV – I SATELLITES OF CONFIGURATION SATELLITES OF 2020 JUPITER OF SATELLITES July BAA Handbook 2020 Satellites of Jupiter 67 December November CONFIGURATION OF SATELLITES I – IV – I SATELLITES OF CONFIGURATION SATELLITES OF 2020 JUPITER OF SATELLITES October

68 Satellites of Jupiter BAA Handbook 2020 ECLIPSES, OCCULTATIONS AND TRANSITS The times are for mid–phenomena, i.e. for eclipses, the planet’s shadow bisecting the satellite; for other events, Jupiter’s limb bisecting the satellite or the satellite shadow. Abbreviations: OcD and OcR occultation disappearance and reappearance EcD and EcR eclipse disappearance and reappearance TrI and TrE transit ingress and egress ShI and ShE shadow–transit ingress and egress

Jupiter in conjunction with the Sun: 2019 December 27d 18h

January January

Occultations and Eclipses Transits and Shadow Transits Date Sat. EcD EcR OcD OcR Date Sat. ShI ShE TrI TrE

21/22 I 23 53 02 34 22 I 21 01 23 15 21 28 23 42 23 II 04 44 08 20 23/24 IV 18 41 21 08 22 57 01 44 23 I 18 21 21 04 24 I 15 30 17 44 15 58 18 13 23/24 III 21 15 02 08 24/25 II 23 50 02 31 00 48 03 30 25 I 12 50 15 35 26 I 09 58 12 12 10 28 12 43 26 II 18 01 21 44 27 III 11 01 13 59 13 07 16 09 27 I 07 18 10 05 28 I 04 27 06 41 04 58 07 13 29 I 01 47 04 35 28 II 13 08 15 48 14 12 16 55 30 II 07 18 11 09 29/30 I 22 55 01 09 23 28 01 43 30 I 20 15 23 05 31 I 17 23 19 38 17 59 20 13 31 III 01 13 06 36 February February

Occultations and Eclipses Transits and Shadow Transits Date Sat. EcD EcR OcD OcR Date Sat. ShI ShE TrI TrE

1 IV 05 29 08 05 11 02 14 01 1 II 02 26 05 06 03 37 06 20 1 I 14 44 17 36 2 I 11 52 14 06 12 29 14 44 2/3 II 20 36 00 33 3 III 15 01 17 59 17 34 20 38 3 I 09 12 12 06 4 I 06 20 08 35 06 59 09 14 5 I 03 41 06 36 4 II 15 43 18 24 17 01 19 44 6 II 09 53 13 58 6 I 00 49 03 03 01 29 03 44 6/7 I 22 09 01 06 7 I 19 17 21 32 19 59 22 14 7 III 05 11 11 03 8 II 05 01 07 42 06 25 09 09 8 I 16 38 19 36 9 IV 12 38 15 17 19 23 22 28 9/10 II 23 10 03 22 9 I 13 46 16 00 14 29 16 44 10 I 11 06 14 06 10/11 III 18 59 21 58 21 58 01 04 12 I 05 35 08 36 11 I 08 14 10 29 08 59 11 14 13 II 12 28 16 46 11 II 18 19 21 00 19 49 22 32 14 I 00 03 03 06 13 I 02 43 04 57 03 29 05 44 14 III 09 10 12 11 12 22 15 29 14/15 I 21 11 23 26 21 59 00 14 15 I 18 31 21 36 15 II 07 36 10 17 09 13 11 56 17 II 01 45 06 10 16 I 15 40 17 54 16 29 18 44 17 I 13 00 16 06 17/18 III 22 57 01 57 02 21 05 28

BAA Handbook 2020 Satellites of Jupiter 69 ECLIPSES, OCCULTATIONS AND TRANSITS February cont'd February cont'd

Occultations and Eclipses Transits and Shadow Transits Date Sat. EcD EcR OcD OcR Date Sat. ShI ShE TrI TrE 17/18 IV 23 25 02 14 07 18 10 35 18 I 10 08 12 22 10 59 13 14 19 I 07 28 10 36 18/19 II 20 54 23 35 22 36 01 20 20 II 15 03 19 34 20 I 04 36 06 51 05 29 07 44 21 I 01 57 05 06 21/22 I 23 05 01 19 23 58 02 14 21 III 13 08 16 10 16 44 19 53 22 II 10 11 12 53 11 59 14 43 22 I 20 25 23 36 23 I 17 33 19 48 18 28 20 43 24 II 04 20 08 57 25 III 02 55 05 57 06 42 09 51 24 I 14 53 18 06 25 I 12 02 14 16 12 58 15 13 26 I 09 22 12 35 25/26 II 23 29 02 10 01 22 04 06 27 II 17 37 22 21 26 IV 06 36 09 27 15 31 18 52 28 I 03 50 07 05 27 I 06 30 08 45 07 28 09 43 28/29 III 17 07 20 10 21 05 00 15 29 I 00 59 03 13 01 58 04 13 29/1 I 22 19 01 35 29 II 12 46 15 27 14 44 17 28

March March

Occultations and Eclipses Transits and Shadow Transits Date Sat. EcD EcR OcD OcR Date Sat. ShI ShE TrI TrE 2 II 06 55 11 43 1 I 19 27 21 42 20 27 22 42 2 I 16 47 20 04 3 III 06 54 09 56 11 02 14 11 4 I 11 16 14 34 3 I 13 56 16 10 14 57 17 12 5/6 IV 17 23 20 23 03 12 06 44 4 II 02 04 04 45 04 06 06 50 5/6 II 20 12 01 07 5 I 08 24 10 38 09 26 11 42 6 I 05 44 09 03 7 I 02 52 05 07 03 56 06 11 6/7 III 21 05 00 09 01 22 04 34 7 II 15 21 18 02 17 28 20 12 8 I 00 12 03 33 8/ 9 I 21 21 23 35 22 26 00 41 9 II 09 30 14 29 10 III 10 53 13 56 15 19 18 31 9 I 18 41 22 02 10 I 15 49 18 04 16 55 19 10 11 I 13 09 16 32 11 II 04 38 07 19 06 50 09 34 12/13 II 22 47 03 51 12 I 10 18 12 32 11 25 13 40 13 I 07 37 11 01 14 IV 00 34 03 35 11 12 14 46 14 III 01 03 04 08 05 37 08 51 14 I 04 46 07 01 05 54 08 09 15 I 02 06 05 31 14 II 17 55 20 37 20 11 22 55 16 II 12 05 17 13 15/16 I 23 15 01 29 00 23 02 39 16/17 I 20 34 00 00 17 III 14 51 17 55 19 34 22 46 18 I 15 02 18 29 17 I 17 43 19 58 18 53 21 08 20 II 01 23 06 35 18 II 07 12 09 54 09 31 12 16 20 I 09 31 12 58 19 I 12 11 14 26 13 22 15 37 21 III 05 01 08 07 09 50 13 04 21 I 06 40 08 54 07 51 10 07 22 I 03 59 07 27 21/22 II 20 30 23 11 22 51 01 36 22/23 IV 11 21 14 31 22 36 02 20 23 I 01 08 03 23 02 20 04 36 23 II 14 40 19 56 24/25 III 18 50 21 55 23 46 02 59 23/24 I 22 27 01 57 24 I 19 37 21 51 20 50 23 05 25 I 16 56 20 26 25 II 09 47 12 28 12 11 14 56 27 II 03 58 09 17 26 I 14 05 16 20 15 19 17 34

70 Satellites of Jupiter BAA Handbook 2020 ECLIPSES, OCCULTATIONS AND TRANSITS

March cont'd March cont'd

Occultations and Eclipses Transits and Shadow Transits Date Sat. EcD EcR OcD OcR Date Sat. ShI ShE TrI TrE

27 I 11 24 14 55 28 I 08 34 10 48 09 48 12 03 28 III 08 59 12 06 13 59 17 15 28/29 II 23 04 01 45 01 31 04 15 29 I 05 52 09 24 30 I 03 02 05 17 04 17 06 32 30 II 17 15 22 37 30/31 IV 18 32 21 44 06 19 10 04 31 I 00 21 03 52 31/ 1 I 21 30 23 45 22 46 01 01 31/ 1 III 22 49 01 54 03 54 07 09

April April

Occultations and Eclipses Transits and Shadow Transits Date Sat. EcD EcR OcD OcR Date Sat. ShI ShE TrI TrE 1 I 18 49 22 21 1 II 12 20 15 02 14 50 17 35 3 II 06 33 11 58 2 I 15 59 18 13 17 15 19 30 3 I 13 17 16 50 4 I 10 27 12 42 11 44 13 59 4 III 12 57 16 05 18 06 21 23 5 II 01 37 04 19 04 08 06 53 5 I 07 46 11 19 6 I 04 56 07 10 06 12 08 28 6/7 II 19 51 01 17 7/ 8 I 23 24 01 39 00 41 02 57 7 I 02 14 05 47 8 III 02 47 05 53 07 58 11 14 8 IV 05 19 08 39 17 21 21 14 8 II 14 54 17 36 17 26 20 11 8/9 I 20 42 00 16 9 I 17 53 20 07 19 10 21 25 10 II 09 09 14 37 11 I 12 21 14 36 13 38 15 54 10 I 15 11 18 45 12 II 04 11 06 53 06 44 09 29 11/12 III 16 56 20 05 22 09 01 27 13 I 06 49 09 04 08 07 10 22 12 I 09 39 13 13 15 I 01 18 03 33 02 36 04 51 13/14 II 22 26 03 55 15 III 06 45 09 52 11 59 15 16 14 I 04 07 07 41 15 II 17 28 20 10 20 01 22 46 15/16 I 22 36 02 10 16/17 IV 12 32 15 52 00 43 04 36 17 II 11 45 17 14 16 I 19 46 22 01 21 04 23 19 17 I 17 04 20 38 18 I 14 15 16 29 15 32 17 48 18/19 III 20 54 00 04 02 08 05 27 19 II 06 45 09 27 09 17 12 03 19 I 11 32 15 06 20 I 08 43 10 58 10 01 12 16 21 II 01 02 06 31 22 I 03 11 05 26 04 29 06 45 21 I 06 00 09 34 22 III 10 43 13 51 15 56 19 14 23 I 00 29 04 03 22/23 II 20 01 22 44 22 33 01 19 24 II 14 20 19 49 23/24 I 21 40 23 55 22 57 01 13 24 I 18 57 22 31 25 I 16 08 18 23 17 25 19 41

BAA Handbook 2020 Satellites of Jupiter 71 ECLIPSES, OCCULTATIONS AND TRANSITS

April cont'd April cont'd

Occultations and Eclipses Transits and Shadow Transits Date Sat. EcD EcR OcD OcR Date Sat. ShI ShE TrI TrE 24/25 IV 23 17 02 46 11 19 15 19 26 II 09 18 12 01 11 49 14 35 26 III 00 52 04 03 06 02 09 22 27 I 10 37 12 52 11 53 14 09 26 I 13 25 16 59 29 I 05 05 07 20 06 21 08 37 28 II 03 38 09 05 29 III 14 42 17 52 19 50 23 08 28 I 07 54 11 27 29/30 II 22 35 01 17 01 04 03 50 30 I 02 22 05 54 30/ 1 I 23 34 01 49 00 49 03 05

May May

Occultations and Eclipses Transits and Shadow Transits Date Sat. EcD EcR OcD OcR Date Sat. ShI ShE TrI TrE

1 II 16 56 22 22 2 I 18 02 20 17 19 17 21 33 1/2 I 20 50 00 22 3 IV 06 30 10 00 18 15 22 15 3 III 04 50 08 02 09 52 13 13 3 II 11 51 14 34 14 18 17 04 3 I 15 18 18 50 4 I 12 30 14 46 13 45 16 01 5 II 06 14 11 37 6 I 06 59 09 14 08 13 10 29 5 I 09 47 13 18 6/ 7 III 18 41 21 51 23 39 02 58 7 I 04 15 07 45 7 II 01 08 03 51 03 32 06 18 8/9 II 19 32 00 52 8 I 01 27 03 42 02 41 04 56 8/9 I 22 43 02 13 9 I 19 56 22 11 21 08 23 24 10 III 08 48 12 00 13 38 16 59 10 II 14 25 17 08 16 46 19 32 10 I 17 12 20 40 11 I 14 24 16 39 15 36 17 52 11/12 IV 17 17 20 54 04 24 08 29 13 I 08 53 11 08 10 03 12 19 12 II 08 50 14 07 13/14 III 22 40 01 51 03 23 06 43 12 I 11 40 15 07 14 II 03 41 06 25 05 59 08 45 14 I 06 08 09 35 15 I 03 21 05 36 04 31 06 47 15/16 II 22 09 03 21 16/17 I 21 49 00 05 22 58 01 14 16 I 00 37 04 02 17 II 16 58 19 41 19 11 21 57 17 III 12 46 15 59 17 20 20 41 18 I 16 18 18 33 17 25 19 41 17 I 19 05 22 29 20 IV 00 30 04 08 10 52 14 55 19 II 11 26 16 34 20 I 10 46 13 02 11 53 14 09 19 I 13 33 16 56 21 III 02 38 05 51 07 03 10 23 21 I 08 02 11 23 21 II 06 14 08 58 08 23 11 09 23 II 00 45 05 47 22 I 05 15 07 30 06 20 08 36 23 I 02 30 05 50 23/24 I 23 43 01 59 00 47 03 03 24/25 III 16 45 19 59 20 57 00 19 24/25 II 19 31 22 15 21 34 00 20 24/25 I 20 58 00 17 25 I 18 12 20 27 19 14 21 30 26 II 14 03 18 59 27 I 12 40 14 56 13 41 15 57 26 I 15 26 18 44 28 III 06 36 09 50 10 38 13 58 28 I 09 55 13 11 28 II 08 48 11 32 10 45 13 31 28/29 IV 11 16 15 01 20 31 00 39 29 I 07 09 09 24 08 08 10 24 30 II 03 21 08 11 31 I 01 37 03 53 02 35 04 51 30 I 04 23 07 38 31/ 1 II 22 04 00 49 23 55 02 42 31/1 III 20 43 23 58 00 30 03 52 31/1 I 22 52 02 04 72 Satellites of Jupiter BAA Handbook 2020 ECLIPSES, OCCULTATIONS AND TRANSITS

June June

Occultations and Eclipses Transits and Shadow Transits Date Sat. EcD EcR OcD OcR Date Sat. ShI ShE TrI TrE 2 II 16 39 21 22 1 I 20 05 22 22 21 01 23 18 2 I 17 20 20 31 3 I 14 34 16 50 15 28 17 45 4 I 11 48 14 57 4 III 10 35 13 50 14 08 17 29 6 II 05 58 10 33 4 II 11 21 14 06 13 05 15 51 6 I 06 17 09 24 5 I 09 02 11 19 09 55 12 11 8 III 00 42 03 58 03 59 07 21 5/ 6 IV 18 30 22 16 02 32 06 38 8 I 00 45 03 50 7 I 03 31 05 47 04 21 06 38 9 I 19 13 22 17 8 II 00 37 03 23 02 14 05 01 9 II 19 16 23 43 8/ 9 I 21 59 00 16 22 48 01 04 11 I 13 42 16 43 10 I 16 28 18 44 17 14 19 31 13 I 08 10 11 09 11 II 13 54 16 39 15 23 18 10 13 II 08 34 12 53 11 III 14 33 17 49 17 35 20 56 14 IV 05 17 09 09 11 46 15 54 12 I 10 56 13 13 11 41 13 57 15 I 02 38 05 36 14 I 05 25 07 41 06 07 08 24 15 III 04 40 10 46 15 II 03 11 05 56 04 31 07 18 16/17 I 21 07 00 02 15/16 I 23 54 02 10 00 34 02 50 16/17 II 21 52 02 02 17 I 18 22 20 39 19 00 21 17 18 I 15 35 18 28 18 II 16 28 19 13 17 39 20 26 20 I 10 04 12 54 18/19 III 18 33 21 50 20 59 00 20 20 II 11 11 15 12 19 I 12 51 15 07 13 26 15 43 22 I 04 32 07 20 21 I 07 19 09 36 07 52 10 09 22 III 08 39 14 07 22 II 05 44 08 30 06 47 09 34 23/24 I 23 01 01 46 22 IV 12 31 16 25 17 23 21 29 24 II 00 29 04 20 23 I 01 48 04 04 02 18 04 35 25 I 17 29 20 12 24 I 20 16 22 33 20 45 23 02 27 I 11 57 14 38 25 II 19 01 21 47 19 54 22 41 27 II 13 48 17 28 25/26 III 22 32 01 50 00 19 03 41 29 I 06 26 09 04 26 I 14 45 17 02 15 11 17 28 29 III 12 37 17 25 28 I 09 13 11 30 09 37 11 54 30/1 IV 23 19 06 27 29 II 08 18 11 05 09 01 11 48 30 I 03 42 05 59 04 03 06 20

BAA Handbook 2020 Satellites of Jupiter 73 ECLIPSES, OCCULTATIONS AND TRANSITS

July July

Occultations and Eclipses Transits and Shadow Transits Date Sat. EcD EcR OcD OcR Date Sat. ShI ShE TrI TrE 1 I 00 54 03 30 1/ 2 I 22 11 00 28 22 29 00 46 1 II 03 06 06 36 2/ 3 II 21 35 00 22 22 08 00 55 2 I 19 23 21 56 3 III 02 32 05 51 03 38 07 00 4 I 13 51 16 22 3 I 16 39 18 56 16 55 19 12 4 II 16 25 19 44 5 I 11 08 13 25 11 21 13 38 6 I 08 20 10 48 6 II 10 52 13 39 11 15 14 02 6 III 16 36 20 42 7 I 05 36 07 53 05 47 08 04 8 I 02 48 05 14 9 I 00 05 02 22 00 13 02 30 8 II 05 43 08 52 9 IV 06 34 10 35 07 41 11 47 9 I 21 17 23 40 10 II 00 09 02 56 00 22 03 09 11 I 15 45 18 06 10 III 06 31 09 51 06 55 10 16 11 II 19 02 22 00 10 I 18 34 20 51 18 39 20 56 13 I 10 14 12 31 12 I 13 02 15 20 13 05 15 22 13 III 20 36 23 59 13 II 13 26 16 14 13 28 16 16

Jupiter in Opposition to the Sun: 2020 July 14d 08h

July cont'd July cont'd

Occultations and Eclipses Transits and Shadow Transits Date Sat. OcD OcR EcD EcR Date Sat. TrI TrE ShI ShE 15 I 04 41 06 58 14 I 07 31 09 48 07 31 09 48 15 II 08 17 11 10 16 I 01 57 04 14 02 00 04 17 16/17 I 23 07 01 27 17 II 02 35 05 22 02 43 05 31 17 IV 16 32 21 27 17 III 10 11 13 32 10 30 13 51 18 I 17 33 19 56 17 I 20 23 22 40 20 28 22 46 18/19 II 21 25 00 29 19 I 14 49 17 06 14 57 17 14 20 I 11 59 14 24 20 II 15 42 18 29 16 01 18 48 20/21 III 23 54 03 57 21 I 09 15 11 32 09 26 11 43 22 I 06 25 08 53 23 I 03 41 05 58 03 55 06 12 22 II 10 32 13 47 24 II 04 49 07 36 05 18 08 06 24 I 00 51 03 21 24 III 13 27 16 48 14 30 17 52 25 I 19 17 21 50 24/25 I 22 07 00 24 22 23 00 40 25/26 II 23 41 03 06 25/26 IV 21 53 01 58 00 38 04 45 27 I 13 43 16 19 26 I 16 33 18 50 16 52 19 09 28 III 03 12 07 57 27 II 17 56 20 43 18 35 21 23 29 I 08 09 10 47 28 I 11 00 13 16 11 21 13 38 29 II 12 48 16 25 30 I 05 26 07 43 05 50 08 07 31 I 02 35 05 16 31 II 07 03 09 50 07 53 10 41 31 III 16 46 20 06 18 30 21 52 31/1 I 23 52 02 09 00 18 02 35 74 Satellites of Jupiter BAA Handbook 2020 ECLIPSES, OCCULTATIONS AND TRANSITS

August August

Occultations and Eclipses Transits and Shadow Transits Date Sat. OcD OcR EcD EcR Date Sat. TrI TrE ShI ShE 1 I 21 01 23 45 2 I 18 18 20 35 18 47 21 04 2 II 01 57 05 44 3 II 20 11 22 58 21 10 23 58 3 IV 06 50 10 56 11 25 15 36 4 I 12 45 15 01 13 16 15 33 3 I 15 27 18 13 6 I 07 11 09 28 07 45 10 01 4 III 06 32 11 58 7 II 09 19 12 06 10 28 13 16 5 I 09 53 12 42 7/ 8 III 20 07 23 27 22 31 01 53 5 II 15 06 19 02 8 I 01 37 03 54 02 13 04 30 7 I 04 20 07 10 9 I 20 04 22 21 20 42 22 59 8/9 I 22 46 01 39 10/11 II 22 28 01 15 23 45 02 34 9 II 04 15 08 21 11 IV 12 23 16 27 18 43 22 55 10 I 17 12 20 08 11 I 14 30 16 47 15 11 17 28 11 III 09 53 15 58 13 I 08 57 11 14 09 40 11 56 12 I 11 39 14 37 14 II 11 37 14 24 13 03 15 51 12 II 17 24 21 39 14/15 III 23 31 02 51 02 31 05 54 14 I 06 05 09 05 15 I 03 24 05 40 04 08 06 25 16 I 00 32 03 34 16/17 I 21 51 00 07 22 37 00 54 16 II 06 35 10 58 18 II 00 46 03 33 02 21 05 09 17 I 18 58 22 03 18 I 16 17 18 34 17 06 19 23 18 III 13 18 19 58 20 I 10 44 13 00 11 35 13 51 19 I 13 25 16 31 21 II 13 56 16 43 15 39 18 27 19/20 II 19 45 00 17 22 III 02 59 06 19 06 32 09 55 19/20 IV 21 40 01 46 05 31 09 47 22 I 05 11 07 27 06 04 08 20 21 I 07 52 11 00 23/24 I 23 38 01 54 00 32 02 49 23 I 02 19 05 29 25 II 03 07 05 53 04 56 07 45 23 II 08 56 13 36 25 I 18 05 20 21 19 01 21 18 24 I 20 46 23 58 27 I 12 32 14 48 13 30 15 46 25 III 16 47 20 08 20 34 23 59 28 IV 03 36 07 39 12 49 17 06 26 I 15 13 18 26 28 II 16 18 19 04 18 14 21 03 26/27 II 22 07 02 54 29 III 06 31 09 50 10 32 13 56 28 I 09 40 12 55 29 I 06 59 09 15 07 59 10 15 30 I 04 07 07 24 31 I 01 27 03 43 02 28 04 44 30 II 11 19 16 13 31/1 I 22 34 01 53

September September

Occultations and Eclipses Transits and Shadow Transits Date Sat. OcD OcR EcD EcR Date Sat. TrI TrE ShI ShE 1/2 III 20 22 23 42 00 34 04 00 1 II 05 29 08 16 07 32 10 21 2 I 17 01 20 22 1 I 19 54 22 10 20 56 23 13 3 II 00 31 05 31 3 I 14 21 16 37 15 25 17 42 BAA Handbook 2020 Satellites of Jupiter 75 ECLIPSES, OCCULTATIONS AND TRANSITS

September cont'd September cont'd

Occultations and Eclipses Transits and Shadow Transits Date Sat. OcD OcR EcD EcR Date Sat. TrI TrE ShI ShE 4 I 11 28 14 50 4 II 18 42 21 28 20 50 23 39 5/6 IV 13 19 17 25 23 37 03 58 5 I 08 49 11 05 09 54 12 10 6 I 05 56 09 19 5 III 10 07 13 26 14 32 17 56 6 II 13 45 18 50 7 I 03 16 05 32 04 23 06 39 8 I 00 23 03 48 8 II 07 54 10 41 10 08 12 57 9 III 00 00 03 21 04 35 08 01 8/ 9 I 21 44 00 00 22 52 01 08 9 I 18 51 22 17 10 I 16 12 18 27 17 21 19 37 10 II 02 58 08 09 11/12 II 21 08 23 54 23 27 02 16 11 I 13 18 16 45 12 I 10 39 12 55 11 49 14 06 13 I 07 46 11 14 12 III 13 47 17 07 18 32 21 57 13 II 16 12 21 27 13/14 IV 19 44 23 47 06 57 11 18 15 I 02 14 05 43 14 I 05 07 07 23 06 18 08 34 16 III 03 44 07 05 08 36 12 03 15 II 10 22 13 08 12 45 15 34 16/17 I 20 42 00 12 15/16 I 23 35 01 51 00 47 03 03 17 II 05 27 10 46 17 I 18 03 20 19 19 16 21 32 18 I 15 10 18 41 18/19 II 23 36 02 23 02 03 04 52 20 I 09 38 13 10 19 I 12 31 14 47 13 45 16 01 20/21 II 18 42 00 04 19/20 III 17 33 20 52 22 32 01 58 22 I 04 06 07 39 21 I 06 59 09 15 08 14 10 30 22 IV 05 55 10 03 17 43 22 09 22 II 12 52 15 38 15 21 18 11 23 III 07 31 10 53 12 36 16 04 23 I 01 27 03 43 02 42 04 58 23/24 I 22 34 02 07 24 I 19 56 22 11 21 11 23 27 24 II 07 58 13 23 26 II 02 07 04 54 04 40 07 29 25 I 17 02 20 36 26 I 14 24 16 40 15 40 17 56 27 I 11 31 15 05 26/27 III 21 24 00 43 02 34 06 00 27/28 II 21 15 02 41 28 I 08 52 11 08 10 09 12 25 29 I 05 59 09 34 29 II 15 24 18 11 17 58 20 48 30 III 11 23 14 45 16 36 20 04 30 I 03 21 05 36 04 38 06 54 30/ 1 IV 12 50 16 56 01 04 05 29

October October

Occultations and Eclipses Transits and Shadow Transits Date Sat. TrI TrE ShI ShE Date Sat. OcD OcR EcD EcR 1 I 00 27 04 03 1/ 2 I 21 49 00 05 23 07 01 23 1 II 10 31 15 59 3 II 04 41 07 28 07 17 10 06 2 I 18 56 22 32 3 I 16 18 18 33 17 36 19 51 4 I 13 24 17 01 4 III 01 18 04 38 06 35 10 01 4/5 II 23 49 05 18 5 I 10 47 13 02 12 04 14 20 6 I 07 53 11 29 6 II 17 58 20 46 20 35 23 25 7/8 III 15 19 18 42 20 36 00 05 7 I 05 15 07 31 06 33 08 49 76 Satellites of Jupiter BAA Handbook 2020 ECLIPSES, OCCULTATIONS AND TRANSITS October cont'd October cont'd

Occultations and Eclipses Transits and Shadow Transits Date Sat. OcD OcR EcD EcR Date Sat. TrI TrE ShI ShE 8 I 02 22 05 58 8 II 13 07 18 36 8/ 9 I 23 44 02 00 01 02 03 18 8/9 IV 23 31 03 42 11 50 16 20 10 II 07 17 10 04 09 54 12 44 9/10 I 20 51 00 27 10 I 18 13 20 28 19 31 21 47 11 I 15 19 18 56 11 III 05 18 08 38 10 36 14 03 12 II 02 25 07 55 12 I 12 42 14 57 14 00 16 16 13 I 09 48 13 25 13/14 II 20 35 23 23 23 12 02 02 14/15 III 19 20 22 43 00 37 04 07 14 I 07 11 09 26 08 29 10 44 15 I 04 17 07 54 16 I 01 40 03 55 02 57 05 13 15 II 15 44 21 13 17 IV 06 52 11 02 19 12 23 42 16/17 I 22 46 02 23 17 II 09 54 12 42 12 31 15 21 18 I 17 15 20 52 17 I 20 09 22 24 21 26 23 42 19 II 05 03 10 31 18 III 09 21 12 42 14 36 18 04 20 I 11 45 15 21 19 I 14 38 16 53 15 55 18 11 21/22 III 23 26 02 49 04 38 08 09 20/21 II 23 14 02 02 01 49 04 40 22 I 06 14 09 50 21 I 09 07 11 23 10 24 12 40 22 II 18 23 23 49 23 I 03 36 05 52 04 53 07 09 24 I 00 43 04 18 24 II 12 34 15 23 15 08 17 59 25/26 IV 17 59 22 14 05 58 10 32 24/25 I 22 06 00 21 23 21 01 37 25 I 19 12 22 47 25 III 13 27 16 49 18 36 22 05 26 II 07 43 13 07 26 I 16 35 18 50 17 50 20 06 27 I 13 42 17 16 28 II 01 55 04 43 04 27 07 18 29 III 03 34 06 59 08 39 12 10 28 I 11 04 13 20 12 19 14 35 29 I 08 11 11 45 30 I 05 34 07 49 06 48 09 04 29/30 II 21 04 02 26 31 II 15 16 18 05 17 46 20 37 31 I 02 41 06 14

November November

Occultations and Eclipses Transits and Shadow Transits Date Sat. OcD OcR EcD EcR Date Sat. TrI TrE ShI ShE 1/2 I 21 10 00 43 1 I 00 03 02 19 01 17 03 33 2 II 10 25 15 44 1/ 2 III 17 37 21 00 22 37 02 06 3 I 15 40 19 12 2 I 18 33 20 48 19 46 22 02 5 III 07 47 11 12 12 40 16 12 3 IV 01 45 06 00 13 21 17 55 5 I 10 10 13 41 4 II 04 37 07 26 07 04 09 56 5/6 II 23 46 05 02 4 I 13 02 15 18 14 14 16 30 7 I 04 39 08 10 6 I 07 32 09 47 08 43 10 59 8/9 I 23 09 02 39 7 II 17 59 20 49 20 24 23 15 9 II 13 08 18 20 8 I 02 01 04 17 03 12 05 28 10 I 17 39 21 07 8/ 9 III 21 51 01 15 02 37 06 07 11/12 IV 13 12 17 33 00 05 04 43 9 I 20 31 22 47 21 41 23 57 12 III 12 02 15 28 16 41 20 13 11 II 07 22 10 11 09 42 12 34 12 I 12 09 15 36 11 I 15 01 17 16 16 09 18 26 13 II 02 29 07 38 13 I 09 30 11 46 10 38 12 54 14 I 06 38 10 05 14/15 II 20 45 23 35 23 01 01 54 16 I 01 08 04 34 15 I 04 00 06 16 05 07 07 23 16 II 15 52 20 56 16 III 02 08 05 33 06 39 10 09 17 I 19 38 23 03 16/17 I 22 30 00 46 23 36 01 52 19 I 14 08 17 32 18 II 10 08 12 58 12 20 15 12 19/20 III 16 20 19 47 20 41 00 13 18 I 17 00 19 16 18 05 20 21 BAA Handbook 2020 Satellites of Jupiter 77 ECLIPSES, OCCULTATIONS AND TRANSITS

November cont'd November cont'd

Occultations and Eclipses Transits and Shadow Transits Date Sat. OcD OcR EcD EcR Date Sat. TrI TrE ShI ShE

20 II 05 14 10 14 19/20 IV 21 18 01 40 07 30 12 08 21 I 08 38 12 01 20 I 11 30 13 46 12 33 14 50 23 I 03 08 06 30 21/22 II 23 31 02 22 01 39 04 32 23 II 18 37 23 31 22 I 06 00 08 16 07 02 09 18 24/25 I 21 39 00 59 23 III 06 27 09 53 10 39 14 11 26 I 16 09 19 28 24 I 00 30 02 46 01 31 03 47 26/27 III 20 40 00 08 00 41 04 14 25 II 12 55 15 46 14 58 17 51 27 II 08 00 12 49 25 I 19 00 21 16 20 00 22 16 28 IV 09 02 13 30 18 14 22 54 27 I 13 30 15 46 14 28 16 45 28 I 10 39 13 56 29 II 02 19 05 11 04 17 07 10 30 I 05 09 08 25 29 I 08 00 10 16 08 57 11 14 30/1 II 21 23 02 07 30 III 10 49 14 16 14 40 18 12

December December

Occultations and Eclipses Transits and Shadow Transits Date Sat. OcD OcR EcD EcR Date Sat. TrI TrE ShI ShE

1/2 I 23 39 02 54 1 I 02 30 04 46 03 26 05 42 3 I 18 10 21 23 2 II 15 43 18 35 17 36 20 29 4 III 01 03 04 32 04 42 08 16 2/ 3 I 21 00 23 16 21 54 00 11 4 II 10 46 15 25 4 I 15 30 17 46 16 23 18 40 5 I 12 40 15 52 6 II 05 08 08 00 06 55 09 49 7 I 07 10 10 21 6 I 10 00 12 16 10 52 13 09 8 II 00 10 04 43 6/ 7 IV 17 25 21 54 01 39 06 20 9 I 01 40 04 50 7 III 15 12 18 41 18 40 22 13 10 I 20 11 23 19 8 I 04 30 06 47 05 21 07 37 11 III 05 28 12 17 9 II 18 33 21 25 20 14 23 08 11 II 13 33 18 00 9/10 I 23 00 01 17 23 49 02 06 12 I 14 41 17 47 11 I 17 31 19 47 18 18 20 35 14 I 09 12 12 16 13 II 07 59 10 51 09 33 12 27 15 II 02 57 07 18 13 I 12 01 14 17 12 47 15 04 15 IV 05 21 09 54 12 22 17 05 14/15 III 19 37 23 07 22 40 02 14 16 I 03 42 06 45 15 I 06 31 08 48 07 15 09 32 17/18 I 22 13 01 14 16/17 II 21 24 00 16 22 52 01 46 18 III 09 55 16 19 17 I 01 01 03 18 01 44 04 01 18 II 16 21 20 36 18 I 19 32 21 48 20 13 22 30 19 I 16 43 19 43 20 II 10 50 13 43 12 12 15 06 21 I 11 14 14 12 20 I 14 02 16 18 14 41 16 58 22 II 05 45 09 53 22 III 00 04 03 35 02 40 06 14 23 I 05 44 08 40 22 I 08 32 10 49 09 10 11 27 25 I 00 15 03 09 23/24 IV 13 56 18 32 19 49 00 33 25 III 14 23 20 20 24 II 00 15 03 08 01 30 04 24 25 II 19 10 23 11 24 I 03 02 05 19 03 39 05 56 26 I 18 45 21 38 25/26 I 21 33 23 50 22 07 00 24 28 I 13 16 16 07 27 II 13 41 16 35 14 50 17 44 29 II 08 34 12 28 27 I 16 03 18 20 16 36 18 53 30 I 07 46 10 36 29 III 04 32 08 04 06 40 10 15 32 IV 01 58 11 15 29 I 10 33 12 50 11 05 13 22 32 I 02 17 05 05 31 II 03 07 06 01 04 08 07 03 78 Satellites of Jupiter BAA Handbook 2020 SATURN Opposition: July 20 Conjunction: January 13

2020 Rings Equat Polar Major Minor RA Dec. Mag D Δ Diam. Diam. Axis Axis E h m º ' " " " " º au Jan. 2 19 33.0 –21 40 0.5 15.1 13.9 34.3 13.6 23.5 11.000 Jan. 12 19 38.0 –21 29 0.5 15.1 13.8 34.2 13.5 23.1 11.016 Jan. 22 19 43.0 –21 18 0.5 15.1 13.9 34.3 13.3 22.8 11.007 Feb. 1 19 47.9 –21 06 0.6 15.1 13.9 34.4 13.1 22.5 10.972 Feb. 11 19 52.7 –20 55 0.6 15.2 14.0 34.6 13.0 22.2 10.911 Feb. 21 19 57.3 –20 43 0.6 15.3 14.1 34.8 13.0 21.8 10.828 Mar. 2 20 01.5 –20 32 0.7 15.5 14.2 35.2 12.9 21.5 10.722 Mar. 12 20 05.3 –20 21 0.7 15.7 14.4 35.6 12.9 21.3 10.598 Mar. 22 20 08.7 –20 12 0.7 15.9 14.5 36.1 12.9 21.0 10.457 Apr. 1 20 11.6 –20 04 0.7 16.1 14.8 36.6 13.0 20.8 10.304 Apr. 11 20 13.9 –19 57 0.6 16.4 15.0 37.2 13.1 20.6 10.143 Apr. 21 20 15.6 –19 53 0.6 16.7 15.2 37.8 13.2 20.5 9.976 May 1 20 16.6 –19 51 0.6 16.9 15.5 38.4 13.4 20.4 9.810 May 11 20 17.0 –19 50 0.5 17.2 15.8 39.1 13.6 20.4 9.648 May 21 20 16.7 –19 52 0.5 17.5 16.0 39.7 13.9 20.5 9.495 May 31 20 15.7 –19 56 0.4 17.8 16.2 40.3 14.2 20.6 9.356 Jun. 10 20 14.1 –20 02 0.4 18.0 16.5 40.8 14.4 20.7 9.235 Jun. 20 20 12.0 –20 10 0.3 18.2 16.6 41.3 14.7 20.9 9.135 Jun. 30 20 09.5 –20 19 0.2 18.3 16.8 41.6 15.0 21.1 9.060 Jul. 10 20 06.6 –20 29 0.2 18.4 16.9 41.8 15.2 21.3 9.013 Jul. 20 20 03.5 –20 39 0.1 18.5 16.9 41.9 15.4 21.6 8.995 Jul. 30 20 00.5 –20 48 0.1 18.5 16.9 41.9 15.6 21.8 9.007 Aug. 9 19 57.5 –20 57 0.2 18.4 16.8 41.7 15.7 22.1 9.047 Aug. 19 19 54.9 –21 05 0.2 18.2 16.7 41.4 15.7 22.3 9.116 Aug. 29 19 52.7 –21 12 0.3 18.0 16.5 40.9 15.6 22.5 9.211 Sep. 8 19 51.0 –21 17 0.3 17.8 16.3 40.4 15.5 22.6 9.328 Sep. 18 19 49.9 –21 21 0.4 17.6 16.1 39.9 15.4 22.7 9.464 Sep. 28 19 49.4 –21 22 0.4 17.3 15.9 39.2 15.1 22.7 9.614 Oct. 8 19 49.7 –21 22 0.5 17.0 15.6 38.6 14.9 22.7 9.774 Oct. 18 19 50.7 –21 20 0.5 16.7 15.3 37.9 14.6 22.6 9.939 Oct. 28 19 52.3 –21 16 0.6 16.4 15.1 37.3 14.3 22.5 10.104 Nov. 7 19 54.6 –21 11 0.6 16.2 14.8 36.7 14.0 22.4 10.265 Nov. 17 19 57.5 –21 03 0.6 16.0 14.6 36.2 13.7 22.2 10.418 Nov. 27 20 00.9 –20 54 0.6 15.7 14.4 35.7 13.3 21.9 10.557 Dec. 7 20 04.7 –20 43 0.6 15.6 14.3 35.3 13.0 21.6 10.681 Dec. 17 20 09.0 –20 31 0.6 15.4 14.1 35.0 12.7 21.3 10.785 Dec. 27 20 13.5 –20 18 0.6 15.3 14.0 34.7 12.4 21.0 10.867

Description of the headings in the table can be found on page 22. BAA Handbook 2020 Saturn 79 LONGITUDE OF CENTRAL MERIDIAN OF SATURN SYSTEM I Day Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. º º º º º º º º º º º º 1 218.7 108.3 110.9 3.7 133.9 29.8 161.7 57.5 311.5 79.2 329.1 93.7 2 342.8 232.5 235.2 128.1 258.3 154.2 286.1 181.8 75.8 203.4 93.2 217.8 3 107.0 356.7 359.4 252.4 22.7 278.6 50.5 306.2 200.1 327.6 217.4 342.0 4 231.2 120.9 123.7 16.7 147.0 42.9 174.9 70.5 324.4 91.8 341.6 106.1 5 355.3 245.1 248.0 141.0 271.4 167.3 299.3 194.9 88.7 216.0 105.7 230.3

6 119.5 9.3 12.2 265.3 35.8 291.7 63.7 319.2 213.0 340.2 229.9 354.4 7 243.6 133.5 136.5 29.7 160.1 56.1 188.1 83.6 337.2 104.4 354.0 118.5 8 7.8 257.7 260.8 154.0 284.5 180.5 312.5 207.9 101.5 228.6 118.2 242.7 9 132.0 22.0 25.0 278.3 48.9 304.9 76.9 332.3 225.8 352.8 242.4 6.8 10 256.2 146.2 149.3 42.6 173.3 69.3 201.2 96.6 350.1 117.0 6.5 131.0

11 20.3 270.4 273.6 167.0 297.6 193.7 325.6 221.0 114.3 241.2 130.7 255.1 12 144.5 34.6 37.8 291.3 62.0 318.1 90.0 345.3 238.6 5.4 254.8 19.3 13 268.7 158.8 162.1 55.6 186.4 82.5 214.4 109.6 2.8 129.6 19.0 143.4 14 32.9 283.1 286.4 180.0 310.8 206.9 338.8 234.0 127.1 253.8 143.1 267.6 15 157.0 47.3 50.7 304.3 75.2 331.3 103.2 358.3 251.4 18.0 267.3 31.7

16 281.2 171.5 175.0 68.7 199.5 95.7 227.6 122.6 15.6 142.2 31.4 155.9 17 45.4 295.7 299.2 193.0 323.9 220.1 351.9 246.9 139.9 266.4 155.6 280.0 18 169.6 60.0 63.5 317.3 88.3 344.5 116.3 11.3 264.1 30.6 279.7 44.2 19 293.8 184.2 187.8 81.7 212.7 108.9 240.7 135.6 28.4 154.8 43.9 168.3 20 57.9 308.5 312.1 206.0 337.1 233.3 5.1 259.9 152.6 279.0 168.0 292.4

21 182.1 72.7 76.4 330.4 101.5 357.7 129.4 24.2 276.9 43.2 292.2 56.6 22 306.3 196.9 200.7 94.7 225.8 122.1 253.8 148.5 41.1 167.3 56.3 180.7 23 70.5 321.2 325.0 219.1 350.2 246.5 18.2 272.8 165.3 291.5 180.5 304.9 24 194.7 85.4 89.3 343.4 114.6 10.9 142.6 37.2 289.6 55.7 304.6 69.0 25 318.9 209.7 213.6 107.8 239.0 135.3 266.9 161.5 53.8 179.9 68.8 193.2

26 83.1 333.9 337.9 232.1 3.4 259.7 31.3 285.8 178.0 304.0 192.9 317.4 27 207.3 98.2 102.2 356.5 127.8 24.1 155.7 50.1 302.3 68.2 317.1 81.5 28 331.5 222.4 226.5 120.9 252.2 148.5 280.0 174.4 66.5 192.4 81.2 205.7 29 95.7 346.7 350.8 245.2 16.6 272.9 44.4 298.7 190.7 316.6 205.4 329.8 30 219.9 115.1 9.6 141.0 37.3 168.8 63.0 314.9 80.7 329.5 94.0

31 344.1 239.4 265.4 293.1 187.3 204.9 218.1

CHANGE OF LONGITUDE IN INTERVALS OF MEAN TIME h º h º m º m º m º 1 35.18 7 246.25 10 5.86 1 0.59 6 3.52 2 70.36 8 281.43 20 11.73 2 1.17 7 4.10 3 105.54 9 316.61 30 17.59 3 1.76 8 4.69 4 140.72 10 351.79 40 23.45 4 2.35 9 5.28 5 175.90 11 386.97 50 29.32 5 2.93 10 5.86 6 211.07 12 422.15 60 35.18

System I applies to all objects situated on or between the south component of the North Equatorial Belt and the north component of the South Equatorial Belt. 80 Saturn BAA Handbook 2020 LONGITUDE OF CENTRAL MERIDIAN OF SATURN SYSTEM II Day Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. º º º º º º º º º º º º 1 323.7 292.0 77.9 49.4 290.5 264.9 147.8 122.3 95.1 333.8 302.5 178.1 2 55.6 23.9 169.9 141.4 22.5 357.0 239.9 214.3 187.1 65.7 34.3 270.0 3 147.4 115.8 261.8 233.4 114.6 89.1 332.0 306.4 279.0 157.6 126.2 1.8 4 239.3 207.7 353.8 325.4 206.7 181.2 64.1 38.4 11.0 249.5 218.1 93.7 5 331.2 299.6 85.7 57.4 298.7 273.3 156.2 130.5 103.0 341.4 309.9 185.5

6 63.0 31.5 177.7 149.4 30.8 5.4 248.3 222.5 195.0 73.3 41.8 277.4 7 154.9 123.5 269.7 241.5 122.8 97.5 340.4 314.6 287.0 165.3 133.7 9.2 8 246.8 215.4 1.6 333.5 214.9 189.6 72.4 46.6 19.0 257.2 225.5 101.1 9 338.6 307.3 93.6 65.5 307.0 281.7 164.5 138.7 110.9 349.1 317.4 192.9 10 70.5 39.2 185.6 157.5 39.1 13.8 256.6 230.7 202.9 81.0 49.2 284.8

11 162.4 131.1 277.5 249.6 131.1 105.9 348.7 322.7 294.9 172.9 141.1 16.6 12 254.3 223.0 9.5 341.6 223.2 198.0 80.8 54.8 26.8 264.8 233.0 108.5 13 346.1 315.0 101.5 73.6 315.3 290.0 172.9 146.8 118.8 356.7 324.8 200.3 14 78.0 46.9 193.5 165.7 47.4 22.1 265.0 238.8 210.8 88.6 56.7 292.2 15 169.9 138.8 285.4 257.7 139.4 114.2 357.0 330.9 302.7 180.5 148.5 24.0

16 261.8 230.7 17.4 349.7 231.5 206.3 89.1 62.9 34.7 272.4 240.4 115.9 17 353.6 322.7 109.4 81.8 323.6 298.4 181.2 154.9 126.6 4.3 332.2 207.7 18 85.5 54.6 201.4 173.8 55.7 30.5 273.3 247.0 218.6 96.1 64.1 299.6 19 177.4 146.5 293.4 265.8 147.8 122.6 5.4 339.0 310.5 188.0 155.9 31.4 20 269.3 238.5 25.4 357.9 239.8 214.7 97.4 71.0 42.5 279.9 247.8 123.3

21 1.2 330.4 117.4 89.9 331.9 306.8 189.5 163.0 134.4 11.8 339.6 215.1 22 93.1 62.3 209.3 182.0 64.0 38.9 281.6 255.0 226.4 103.7 71.5 307.0 23 185.0 154.3 301.3 274.0 156.1 131.0 13.7 347.0 318.3 195.6 163.4 38.8 24 276.8 246.2 33.3 6.1 248.2 223.1 105.7 79.1 50.2 287.5 255.2 130.7 25 8.7 338.2 125.3 98.1 340.3 315.2 197.8 171.1 142.2 19.3 347.1 222.5

26 100.6 70.1 217.3 190.2 72.4 47.3 289.9 263.1 234.1 111.2 78.9 314.4 27 192.5 162.1 309.3 282.2 164.4 139.4 21.9 355.1 326.0 203.1 170.8 46.2 28 284.4 254.0 41.3 14.3 256.5 231.5 114.0 87.1 58.0 295.0 262.6 138.1 29 16.3 346.0 133.3 106.3 348.6 323.6 206.1 179.1 149.9 26.8 354.5 229.9 30 108.2 225.3 198.4 80.7 55.7 298.1 271.1 241.8 118.7 86.3 321.8

31 200.1 317.4 172.8 30.2 3.1 210.6 53.7

CHANGE OF LONGITUDE IN INTERVALS OF MEAN TIME h º h º m º m º m º 1 33.83 7 236.83 10 5.64 1 0.56 6 3.38 2 67.67 8 270.67 20 11.28 2 1.13 7 3.95 3 101.50 9 304.50 30 16.92 3 1.69 8 4.51 4 135.33 10 338.33 40 22.56 4 2.26 9 5.08 5 169.17 11 372.17 50 28.19 5 2.82 10 5.64 6 203.00 12 406.00 60 33.83

System II applies to all objects situated north of the south component of the North Equatorial Belt or south of the north component of the South Equatorial Belt. However System III is used more often for these regions. BAA Handbook 2020 Saturn 81 LONGITUDE OF CENTRAL MERIDIAN OF SATURN SYSTEM III Day Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. º º º º º º º º º º º º 1 87.3 18.2 129.1 63.2 268.1 205.1 51.8 348.9 284.3 126.8 58.1 257.7 2 177.9 108.9 219.8 154.0 358.9 296.0 142.7 79.7 15.1 217.5 148.8 348.3 3 268.6 199.6 310.6 244.8 89.8 26.9 233.6 170.6 105.9 308.3 239.5 78.9 4 359.2 290.3 41.3 335.6 180.6 117.8 324.5 261.4 196.7 39.0 330.1 169.6 5 89.9 21.0 132.1 66.4 271.5 208.7 55.4 352.3 287.4 129.7 60.8 260.2

6 180.6 111.7 222.9 157.2 2.4 299.6 146.3 83.1 18.2 220.4 151.4 350.9 7 271.2 202.4 313.6 248.0 93.2 30.4 237.1 174.0 109.0 311.1 242.1 81.5 8 1.9 293.1 44.4 338.8 184.1 121.3 328.0 264.8 199.8 41.8 332.8 172.1 9 92.5 23.8 135.1 69.7 274.9 212.2 58.9 355.6 290.5 132.5 63.4 262.8 10 183.2 114.5 225.9 160.5 5.8 303.1 149.8 86.5 21.3 223.2 154.1 353.4

11 273.9 205.2 316.7 251.3 96.7 34.0 240.7 177.3 112.1 313.9 244.7 84.1 12 4.5 295.9 47.4 342.1 187.5 124.9 331.6 268.1 202.8 44.6 335.4 174.7 13 95.2 26.7 138.2 72.9 278.4 215.8 62.4 359.0 293.6 135.3 66.0 265.4 14 185.9 117.4 229.0 163.8 9.3 306.7 153.3 89.8 24.3 226.0 156.7 356.0 15 276.5 208.1 319.7 254.6 100.2 37.6 244.2 180.6 115.1 316.7 247.3 86.6

16 7.2 298.8 50.5 345.4 191.0 128.5 335.1 271.5 205.8 47.3 338.0 177.3 17 97.9 29.5 141.3 76.3 281.9 219.4 65.9 2.3 296.6 138.0 68.6 267.9 18 188.6 120.3 232.1 167.1 12.8 310.2 156.8 93.1 27.3 228.7 159.3 358.6 19 279.2 211.0 322.8 257.9 103.6 41.1 247.7 183.9 118.1 319.4 249.9 89.2 20 9.9 301.7 53.6 348.8 194.5 132.0 338.6 274.7 208.8 50.1 340.6 179.9

21 100.6 32.4 144.4 79.6 285.4 222.9 69.4 5.5 299.6 140.8 71.2 270.5 22 191.3 123.2 235.2 170.4 16.3 313.8 160.3 96.3 30.3 231.4 161.9 1.1 23 282.0 213.9 326.0 261.3 107.2 44.7 251.2 187.2 121.0 322.1 252.5 91.8 24 12.7 304.6 56.8 352.1 198.0 135.6 342.0 278.0 211.8 52.8 343.1 182.4 25 103.3 35.4 147.6 83.0 288.9 226.5 72.9 8.8 302.5 143.5 73.8 273.1

26 194.0 126.1 238.4 173.8 19.8 317.4 163.8 99.6 33.2 234.1 164.4 3.7 27 284.7 216.9 329.2 264.7 110.7 48.3 254.6 190.4 123.9 324.8 255.1 94.4 28 15.4 307.6 60.0 355.5 201.6 139.2 345.5 281.2 214.7 55.5 345.7 185.0 29 106.1 38.3 150.8 86.4 292.5 230.0 76.3 12.0 305.4 146.1 76.4 275.7 30 196.8 241.6 177.2 23.3 320.9 167.2 102.7 36.1 236.8 167.0 6.3

31 287.5 332.4 114.2 258.0 193.5 327.5 97.0

CHANGE OF LONGITUDE IN INTERVALS OF MEAN TIME h º h º m º m º m º 1 33.78 7 236.48 10 5.63 1 0.56 6 3.38 2 67.57 8 270.26 20 11.26 2 1.13 7 3.94 3 101.35 9 304.05 30 16.89 3 1.69 8 4.50 4 135.13 10 337.83 40 22.52 4 2.25 9 5.07 5 168.92 11 371.61 50 28.15 5 2.82 10 5.63 6 202.70 12 405.40 60 33.78 System III also applies to all objects situated north of the south component of the North Equatorial Belt or south of the north component of the South Equatorial Belt. This longitude system is based upon the rotation period of the planet’s magnetic field as defined by the International Astronomical Union. 82 Saturn BAA Handbook 2020 SATELLITES OF SATURN

MIMAS, ENCELADUS AND TETHYS Mimas Enceladus Tethys Each fourth eastern elongation Each third eastern elongation Each second eastern elongation d h d h d h d h d h d h Jan. 1 15.0 Jul. 4 8.4 Jan. 1 11.3 Jul. 4 11.3 Jan. 2 16.8 Jul. 5 17.6 5 9.5 8 2.9 5 14.0 8 13.9 6 11.4 9 12.2 9 4.0 11 21.3 9 16.7 12 16.6 10 6.1 13 6.8 12 22.5 15 15.8 13 19.4 16 19.2 14 0.8 17 1.4 16 17.0 19 10.2 17 22.1 20 21.8 17 19.5 20 19.9 20 11.5 23 4.7 22 0.8 25 0.4 21 14.1 24 14.5 24 6.0 26 23.1 26 3.5 29 3.1 25 8.8 28 9.1 28 0.5 30 17.6 30 6.2 Aug. 2 5.7 29 3.5 Aug. 1 3.7 31 19.0 Aug. 3 12.0 Feb. 3 8.9 6 8.3 Feb. 1 22.1 4 22.3 Feb. 4 13.5 7 6.5 7 11.6 10 11.0 5 16.8 8 16.8 8 8.0 11 0.9 11 14.3 14 13.6 9 11.5 12 11.4 12 2.5 14 19.4 15 17.0 18 16.2 13 6.1 16 6.0 15 21.0 18 13.8 19 19.7 22 18.9 17 0.8 20 0.6 19 15.5 22 8.3 23 22.4 26 21.5 20 19.5 23 19.2 23 10.0 26 2.8 28 1.1 31 0.2 24 14.1 27 13.8 27 4.5 29 21.2 Mar. 3 3.7 Sep. 4 2.8 28 8.8 31 8.4 Mar. 1 23.0 Sep. 2 15.7 7 6.4 8 5.5 Mar. 3 3.4 Sep. 4 3.0 5 17.5 6 10.2 11 9.1 12 8.1 6 22.1 7 21.6 9 12.0 10 4.6 15 11.8 16 10.8 10 16.7 11 16.2 13 6.5 13 23.1 19 14.5 20 13.4 14 11.4 15 10.8 17 1.0 17 17.6 23 17.1 24 16.1 18 6.0 19 5.4 20 19.5 21 12.1 27 19.8 28 18.7 22 0.7 23 0.0 24 14.0 25 6.5 31 22.5 Oct. 2 21.4 25 19.3 26 18.6 28 8.4 29 1.0 Apr. 5 1.2 7 0.1 29 13.9 30 13.3 Apr. 1 2.9 Oct. 2 19.5 9 3.8 11 2.7 Apr. 2 8.6 Oct. 4 7.9 4 21.4 6 14.0 13 6.5 15 5.4 6 3.2 8 2.5 8 15.9 10 8.5 17 9.1 19 8.1 9 21.8 11 21.2 12 10.4 14 3.0 21 11.8 23 10.8 13 16.5 15 15.8 16 4.8 17 21.5 25 14.5 27 13.5 17 11.1 19 10.4 19 23.3 21 15.9 29 17.1 31 16.1 21 5.7 23 5.1 23 17.8 25 10.4 May 3 19.8 Nov. 4 18.8 25 0.3 26 23.7 27 12.2 29 4.9 7 22.4 8 21.5 28 19.0 30 18.4 May 1 6.7 Nov. 1 23.4 12 1.1 13 0.2 May 2 13.6 Nov. 3 13.0 5 1.2 5 17.9 16 3.7 17 2.9 6 8.2 7 7.7 8 19.6 9 12.4 20 6.4 21 5.6 10 2.8 11 2.3 12 14.1 13 6.9 24 9.0 25 8.3 13 21.4 14 21.0 16 8.6 17 1.4 28 11.6 29 11.0 17 16.0 18 15.6 20 3.0 20 19.9 Jun. 1 14.3 Dec. 3 13.7 21 10.6 22 10.3 23 21.5 24 14.5 5 16.9 7 16.4 25 5.2 26 4.9 27 15.9 28 9.0 9 19.5 11 19.1 28 23.8 29 23.6 31 10.4 Dec. 2 3.5 13 22.2 15 21.8 Jun. 1 18.4 Dec. 3 18.3 Jun. 4 4.8 5 22.0 18 0.8 20 0.5 5 13.0 7 12.9 7 23.3 9 16.5 22 3.4 24 3.2 9 7.6 11 7.6 11 17.7 13 11.0 26 6.1 28 5.9 13 2.1 15 2.3 15 12.2 17 5.5 30 8.7 16 20.7 18 21.0 19 6.6 21 0.0 20 15.3 22 15.6 23 1.1 24 18.5 24 9.9 26 10.3 26 19.5 28 13.0 28 4.5 30 5.0 30 14.0 Jul. 1 23.1

Note: For intervening eastern elongations add: Mimas 0d 22.6h or 1d 21.2h or 2d 19.9h Enceladus 1d 08.9h or 2d 17.8h Tethys 1d 21.3h

BAA Handbook 2020 Satellites of Saturn 83 SATELLITES OF SATURN

DIONE AND RHEA Dione Rhea Each second eastern elongation Each second eastern elongation d h d h d h d h d h d h –––– –– –––– May 28 20.3 Sep. 15 06.6 Jan. 3 21.8 May 9 12.6 Sep. 12 22.3 Feb. 14 19.5 Jun. 3 07.7 20 18.0 12 23.0 18 13.4 21 23.2 20 07.0 8 19.0 26 05.4 22 00.2 27 14.2 Oct. 1 00.0 25 18.5 14 06.3 Oct. 1 16.7 31 01.4 Jun. 5 14.9 10 00.9 Mar. 2 05.9 19 17.6 7 04.1 Feb. 9 02.5 14 15.6 19 01.8 7 17.4 25 04.9 12 15.5 18 03.7 23 16.3 28 02.8 13 04.8 30 16.2 18 03.0 27 04.8 Jul. 2 17.0 Nov. 6 03.8 18 16.3 Jul. 6 03.5 23 14.4 Mar. 7 05.9 11 17.6 15 04.9 24 03.7 11 14.8 29 01.8 16 07.0 20 18.2 24 05.9 29 15.2 17 02.1 Nov. 3 13.2 25 08.0 29 18.9 Dec. 3 07.0 Apr. 4 02.6 22 13.4 9 00.7 Apr. 3 09.0 Aug. 7 19.5 12 08.2 9 14.0 28 00.7 14 12.1 12 10.0 16 20.2 21 09.3 15 01.4 Aug. 2 12.0 19 23.6 21 10.9 25 20.9 30 10.5 20 12.8 7 23.3 25 11.1 30 11.8 Sep. 3 21.6 26 00.2 13 10.6 30 22.5 May 1 11.6 18 21.9 Dec. 6 10.0 6 22.9 24 09.3 11 21.5 Note: For an intervening eastern elongation add: 12 10.3 29 20.6 17 09.0 17 21.7 Sep. 4 07.9 22 20.5 Dione 2d 17.7h 23 09.0 9 19.3 28 08.0 Rhea 4d 12.4h

TITAN AND HYPERION Titan Hyperion E. Elong. Inf. Conj’n W. Elong. Sup. Conj’n E.Elong. W Elong. d h d h d h d h d h d h Jan. 10 13.0 Jan. 14 11.3 18 15.3 22 17.3 Jan. 14 01.9 25 05.8 26 13.8 30 12.1 Feb. 3 16.1 Feb. 7 17.9 Feb. 4 12.4 Feb. 15 16.7 Feb. 11 14.5 Feb. 15 12.9 19 16.9 23 18.4 25 21.9 Mar. 8 02.6 27 15.0 Mar. 2 13.4 Mar. 6 17.3 Mar. 10 18.6 Mar. 18 06.4 29 11.1 Mar. 14 15.3 18 13.7 22 17.5 26 18.6 Apr. 8 13.6 Apr. 19 18.0 30 15.3 Apr. 3 13.6 Apr. 7 17.3 Apr. 11 18.2 29 19.5 May 10 23.4 Apr. 15 14.8 19 13.1 23 16.7 27 17.4 May 21 00.0 Jun. 1 03.2 May 1 14.0 May 5 12.1 May 9 15.7 May 13 16.2 Jun. 11 03.2 22 05.8 17 12.7 21 10.7 25 14.1 29 14.6 Jul. 2 05.5 Jul. 13 07.4 Jun. 2 10.9 Jun. 6 08.9 Jun. 10 12.1 Jun. 14 12.6 23 07.2 Aug. 3 08.8 18 08.8 22 06.6 26 09.8 30 10.3 Aug. 13 09.0 24 10.6 Jul. 4 06.3 Jul. 8 04.1 Jul. 12 07.2 Jul. 16 07.9 Sep. 3 11.5 Sep. 14 13.5 20 03.7 24 01.5 28 04.5 Aug. 1 05.4 24 15.0 Oct. 5 17.9 Aug. 5 01.1 Aug. 8 23.0 Aug. 13 01.9 17 03.0 Oct. 15 19.9 26 23.9 20 22.7 24 20.6 28 23.5 Sep. 2 00.9 Nov. 6 02.2 Nov. 17 07.5 Sep. 5 20.5 Sep. 9 18.5 Sep. 13 21.5 17 23.1 27 09.9 Dec. 8 16.6 21 18.8 25 16.9 29 20.0 Oct. 3 21.8 Dec. 18 18.8 30 02.9 Oct. 7 17.5 Oct. 11 15.8 Oct. 15 19.0 19 20.9 23 16.7 27 15.2 31 18.4 Nov. 4 20.4 Nov. 8 16.4 Nov. 12 15.0 Nov. 16 18.3 20 20.2 24 16.4 28 15.1 Dec. 2 18.6 Dec. 6 20.4 Dec. 10 16.7 Dec. 14 15.6 18 19.1 22 20.8 26 17.3 30 16.3

Position–angle and angular–distances can be obtained from JPL’s Horizons web page at: http://ssd.jpl.nasa.gov/?horizons

84 Satellites of Saturn BAA Handbook 2020 TITAN

Saturn is in conjunction with Sun during January.

BAA Handbook 2020 Satellites of Saturn 85 IAPETUS Iapetus shows variations in brightness, and is always brighter at western elongation than at eastern. The diagrams show the apparent path of Iapetus relative to Saturn, the units being in seconds of arc. Conjunction of Saturn is indicated by the faint portion of the orbit path from Jan.1 to Feb.14 and from Dec.27 to Dec.31. E. Elong. Inf. Conj’n. W. Elong. Sup. Conj’n.

d h d h d h d h Jan. 12 11.4 Feb. 1 02.2 Feb. 20 16.9 Mar. 12 23.0 Apr. 2 11.4 Apr. 21 23.4 May 11 01.2 May 31 19.6 Jun. 20 18.9 Jul. 9 15.8 Jul. 28 13.0 Aug. 17 16.6 Sep. 7 02.2 Sep. 25 20.3 Oct. 15 08.2 Nov. 4 20.3 Nov. 25 21.8 Dec. 15 05.0

86 Satellites of Saturn BAA Handbook 2020 URANUS Uranus is at opposition on October 31, magnitude 5.7, diameter 3.8"

BAA Handbook 2020 Uranus 87 NEPTUNE Neptune is at opposition on September 11, magnitude 7.8, diameter 2.4"

88 Neptune BAA Handbook 2020 Trans–Neptunian & Scattered–Disk Objects

The list comprises the date, magnitude, geocentric position and apparent motion when at opposition in 2020, of the 26 most intrinsically bright objects known as of 2019 May 1. The sizes of the smaller objects listed are often speculative given that they are based on an estimated albedo only. If you wish to observe an object then go to the website of the Minor Planet and Comet Ephemeris Service at: http://www.minorplanetcenter.net/iau/MPEph/MPEph.html

Here you enter the date and the designation of the object(s) you wish to observe. Given the extreme distance of these objects, the geocentric position will be sufficiently accurate for any location on the Earth.

Object Opposition Approx. Motion Number/Name Prov ID Date V H Diam. Δ RA Dec. Speed P km au h m º ' "/min º (136199) Eris 2003 UB313 Oct. 16 18.7 –1.1 2326 94.98 1 45.0 –1 41.4 0.025 252 (134340) Pluto – Jul. 16 14.5 –0.76 2374 33.06 19 41.9 –22 23.3 0.061 257 (136472) Makemake 2005 FY9 Mar. 26 17.1 –0.2 1450 51.70 13 08.3 +23 51.9 0.042 295 (136108) Haumea 2003 EL61 Apr. 16 17.3 0.2 1500* 49.46 14 20.2 +16 29.1 0.043 293 (90377) Sedna 2003 VB12 Nov. 20 20.8 1.5 1030 83.42 3 53.0 +7 54.8 0.026 258 (225088) 2007 OR10 Aug. 27 21.3 1.8 1350 87.52 22 25.9 –11 41.0 0.026 251 (90482) Orcus 2004 DW Mar. 1 19.1 2.2 940 47.13 10 19.1 –11 07.4 0.046 291 (50000) Quaoar 2002 LM60 Jun. 25 18.7 2.4 890 41.82 18 14.0 –15 15.1 0.049 269 2013 FY27 Mar. 7 22.2 3.2 900 78.90 10 49.0 –6 45.0 0.029 295 (229762) 2007 UK126 Dec. 6 19.5 3.3 610 40.64 5 02.5 +2 23.8 0.051 267 (55565) 2002 AW197 Feb. 22 19.9 3.3 730 44.40 9 56.2 –3 15.3 0.048 287 2014 UZ224 Nov. 6 23.0 3.4 635 88.85 3 15.6 –10 01.0 0.026 254 (174567) Varda 2003 MW12 Jun. 13 20.1 3.4 700 45.50 17 31.3 –1 41.7 0.046 274 (55636) 2002 TX300 Oct. 29 19.8 3.4 300 41.94 1 32.6 +36 54.8 0.050 247 (202421) 2005 UQ513 Oct. 20 20.4 3.5 500 46.98 0 56.5 +34 13.9 0.046 245 2018 VG18 Dec. 5 24.6 3.6 500 125** 4 49.9 +18 44.3 0.019 262 (303775) 2005 QU182 Oct. 14 20.9 3.6 420 52.91 1 35.0 –3 08.8 0.040 250 (307261) 2002 MS4 Jul. 5 20.3 3.6 930 45.54 18 49.9 –6 10.4 0.046 266 (208996) 2003 AZ84 Jan. 26 20.1 3.6 700 43.38 8 21.0 +7 56.5 0.050 282 (55637) 2002 UX25 Nov. 9 19.6 3.6 665 39.23 3 07.6 +9 22.6 0.054 251 (28978) Ixion 2001 KX76 Jun. 20 19.5 3.6 650 37.96 17 54.6 –29 49.0 0.054 267 (20000) Varuna 2000 WR106 Jan. 23 20.0 3.6 700 42.99 8 27.8 +27 03.8 0.050 287 (145452) 2005 RN43 Sep. 9 19.8 3.7 680 39.61 23 00.9 +1 18.0 0.052 244 2014 EZ51 May 22 21.2 3.8 660 54.32 15 48.7 –25 54.9 0.039 281 2015 RR245 Oct. 3 21.7 3.8 670 61.02 0 30.6 +6 28.7 0.036 246 (90568) 2004 GV9 May 13 19.8 3.8 680 38.66 15 09.7 –25 31.8 0.053 290

*Haumea is asymmetric in shape being roughly 1940 km x 1530 km x 993 km in size. **2018 VG18 was first detected on 2018 Nov. 10 and is the most distant object ever observed in the Solar System. The observational arc extends just 32 days and so its orbital parameters are relatively approximate. BAA Handbook 2020 Trans-Neptunian Objects 89 DWARF PLANETS (134340) Pluto Pluto is at opposition, in Sagittarius, on July 15 at magnitude 14.3.

Its brightness varies little during the year, ranging in visual magnitude from 14.2 to 14.4. (Charts prepared using GUIDE 8.0. Stars down to magnitude 12.0 are shown.)

90 Dwarf Planets BAA Handbook 2020 DWARF PLANETS (134340) Pluto Detailed charts around the time of opposition.

Jun. 15 to Jul. 15 Jul. 15 to Aug. 15

(The charts show stars down to magnitude 14.) BAA Handbook 2020 Dwarf Planets 91 DWARF PLANETS ORBITAL ELEMENTS The geocentric data below have been extracted from the Minor Planet Center Ephemeris Service at: http://www.minorplanetcenter.net/iau/MPEph/MPEph.html

Equinox J2000, Epoch of the elements, JD 2458600.5, 2019 Apr. 27.0 TT No. Name a e i Node Peri. M au ° ° ° ° 1 Ceres 2.769 0.076 10.594 80.306 73.598 77.372 134340 Pluto 39.846 0.254 17.103 110.297 115.011 41.547 136108 Haumea 43.287 0.192 28.211 122.109 238.562 216.566 136199 Eris 67.745 0.439 44.144 35.904 151.686 205.385 136472 Makemake 45.558 0.158 28.980 79.646 295.080 163.956

More information on asteroids and dwarf planets can be found on the website of the Asteroids and Remote Planets Section at: http://www.britastro.org/asteroids/

EPHEMERIDES The data below have been extracted from the Minor Planet Center Ephemeris Service at: http://www.minorplanetcenter.net/iau/MPEph/MPEph.html

Equinox J2000, Epoch of the elements, JD 2458600.5, 2019 Apr. 27.0 TT

1 Ceres 2020 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Apr. 20 22 13 40.1 –18 53 09 3.303 2.963 61.8 9.2 30 22 25 53.5 –18 16 35 3.183 2.966 68.5 9.2 May 10 22 37 08.9 –17 46 32 3.057 2.969 75.5 9.1 20 22 47 19.5 –17 24 31 2.926 2.971 82.6 9.1 30 22 56 15.3 –17 12 14 2.794 2.974 90.1 9.0

Jun. 9 23 03 45.9 –17 11 12 2.662 2.976 97.8 8.9 19 23 09 39.8 –17 22 48 2.533 2.977 106.0 8.7 29 23 13 43.0 –17 48 05 2.410 2.979 114.5 8.6 Jul. 9 23 15 43.2 –18 27 16 2.296 2.980 123.5 8.4 19 23 15 30.0 –19 19 33 2.195 2.981 132.9 8.3

29 23 12 57.6 –20 22 35 2.111 2.982 142.6 8.1 Aug. 8 23 08 12.2 –21 31 58 2.048 2.982 152.1 7.9 18 23 01 32.0 –22 41 49 2.009 2.982 160.5 7.7 28 22 53 32.2 –23 45 08 1.996 2.982 164.6 7.7 Sep. 7 22 45 02.6 –24 35 16 2.011 2.982 161.0 7.7

17 22 36 57.1 –25 07 38 2.052 2.981 152.7 7.9 27 22 30 07.7 –25 19 56 2.118 2.980 143.0 8.1 Oct. 7 22 25 12.7 –25 12 29 2.206 2.979 133.1 8.3 17 22 22 33.3 –24 47 16 2.310 2.978 123.4 8.4 27 22 22 17.1 –24 06 46 2.429 2.976 114.1 8.6

Nov. 6 22 24 18.6 –23 13 43 2.557 2.974 105.2 8.7 16 22 28 25.6 –22 10 22 2.691 2.972 96.7 8.9 26 22 34 24.2 –20 58 33 2.827 2.970 88.5 9.0 Dec. 6 22 41 57.5 –19 39 45 2.963 2.967 80.7 9.1 16 22 50 50.9 –18 15 08 3.096 2.964 73.1 9.1

92 Dwarf Planets BAA Handbook 2020 DWARF PLANETS 134340 Pluto 2020 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Mar. 21 19 45 51.5 –22 00 27 34.393 34.003 66.2 14.8 Apr. 10 19 46 56.1 –22 00 03 34.077 34.016 85.7 14.8 30 19 47 11.7 –22 01 47 33.752 34.029 105.1 14.8 May 20 19 46 38.8 –22 05 32 33.458 34.043 124.6 14.7 Jun. 9 19 45 23.9 –22 10 59 33.228 34.056 144.1 14.7

29 19 43 38.3 –22 17 30 33.093 34.069 163.6 14.6 Jul. 19 19 41 37.7 –22 24 21 33.067 34.082 176.7 14.5 Aug. 8 19 39 39.8 –22 30 47 33.158 34.095 157.2 14.6 28 19 38 02.0 –22 36 08 33.355 34.108 137.6 14.7 Sep. 17 19 36 59.2 –22 39 54 33.638 34.122 118.0 14.7

136108 Haumea 2020 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jan. 21 14 19 15.3 +15 58 06 50.373 50.440 93.4 17.4 Feb. 10 14 19 22.4 +16 09 19 50.071 50.436 111.2 17.4 Mar. 2 14 18 57.8 +16 21 59 49.814 50.432 128.1 17.3 22 14 18 05.8 +16 34 22 49.631 50.427 142.7 17.3 Apr. 11 14 16 54.4 +16 44 49 49.544 50.423 151.0 17.3

May 1 14 15 33.9 +16 51 57 49.560 50.418 148.1 17.3 21 14 14 15.6 +16 54 50 49.677 50.414 136.4 17.3 Jun. 10 14 13 10.3 +16 53 07 49.877 50.409 121.1 17.4 30 14 12 26.6 +16 46 59 50.137 50.405 104.7 17.4 Jul. 20 14 12 10.4 +16 37 09 50.426 50.401 88.0 17.4

136199 Eris 2020 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jun. 29 1 46 45.2 –1 24 57 96.257 95.974 73.6 18.8 Jul. 19 1 46 56.0 –1 25 47 95.926 95.970 92.2 18.8 Aug. 8 1 46 51.6 –1 28 05 95.599 95.966 110.9 18.8 28 1 46 32.5 –1 31 30 95.313 95.962 129.7 18.8 Sep. 17 1 46 00.7 –1 35 34 95.102 95.958 148.3 18.8

Oct. 7 1 45 20.0 –1 39 42 94.989 95.954 164.7 18.7 27 1 44 35.3 –1 43 20 94.991 95.950 164.6 18.7 Nov. 16 1 43 52.2 –1 45 52 95.109 95.946 147.7 18.8 Dec. 6 1 43 16.4 –1 46 54 95.328 95.942 128.3 18.8 26 1 42 52.4 –1 46 11 95.622 95.937 108.4 18.8

136472 Makemake 2020 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jan. 1 13 10 52.3 +23 04 34 52.513 52.570 92.8 17.2 21 13 11 01.7 +23 14 44 52.217 52.571 110.6 17.1 Feb. 10 13 10 39.5 +23 26 46 51.964 52.573 127.7 17.1 Mar. 1 13 9 49.5 +23 39 00 51.785 52.575 142.5 17.1 21 13 8 39.2 +23 49 39 51.702 52.576 151 17.1

Apr. 10 13 7 18.7 +23 57 13 51.725 52.578 148.1 17.1 30 13 5 59.4 +24 00 38 51.848 52.579 136.2 17.1 May 20 13 4 52.2 +23 59 25 52.056 52.581 120.8 17.1 Jun. 9 13 4 05.8 +23 53 39 52.323 52.582 104.3 17.2 29 13 3 46.2 +23 43 58 52.619 52.584 87.5 17.2

BAA Handbook 2020 Dwarf Planets 93 COMETS The date of perihelion (T), period (P), perihelion distance (q) and the magnitude parameters H and G are given for each comet which comes to perihelion in 2020 and which becomes brighter than magnitude 20 and for other comets which are expected to be brighter than 14th magnitude during the year. The table also gives the date that the comet is expected to be at its brightest, its declination, elongation and expected peak magnitude.

The magnitude parameters are taken from determinations by the Comet Section (rows highlighted in red), or from the elements downloaded from the MPC. The predicted total magnitude is given by:

m1 = H + 2.5 G (log10 r) + 5 (log10 Δ) where Δ is the distance of the comet from Earth and r is its distance from the Sun, both in Astronomical Units.

Note that comets which show bright magnitudes at very small elongations are unlikely to be observable. The table is derived from orbital elements downloaded from the Minor Planet Center (MPC) on 2019 May 13 and it is sorted in order of the date at which the comet reaches its brightest magnitude. A digital version containing more information is available from the Comet Section website at https://britastro.org/comet. This website contains links to many other resources useful to the comet observer, in particular the Comet Section observing guide which is available for download as a PDF.

There are no particularly bright comets due in 2020. The regular return of 2P/Encke which is at perihelion in late July is very poor as seen from the northern hemisphere. It has a small elongation throughout the period that it is reasonably bright and then dives south as the elongation increases in early July.

The brightest periodic comet of the year will probably be 88P/Howell which may reach 9th magnitude at perihelion. From 50° N this is a slow–moving evening object in Virgo for the first part of the year. It will be lost in the summer twilight in June but should be a good southern hemisphere target through perihelion until the end of the year.

29P/Schwassmann–Wachmann is a comet in a nearly circular orbit with a period of 14.8 years. In 2020 it comes to opposition on November 5 in Aries. It is now well north of the celestial equator which makes it a good target from northern latitudes. It spends most of the time at around 16th magnitude but has frequent outbursts. It should be kept under observation as regularly as possible.

C/2017 T2 (PANSTARRS) was discovered as a 20th magnitude object on 2017 October 2 and it comes to perihelion in May when it may reach naked eye visibility. It is very well placed for observation from the UK throughout the first half of the year as a circumpolar object moving from Cassiopeia to Ursa Major.

94 Comets BAA Handbook 2020 COMETS Name T q P H G Date of Dec. Elong. Peak peak at peak Magnitude yyyy– mm–dd au years dd ° ° 168P/Hergenrother 2019–08–05 1.36 6.78 10.3 2.7 Jan. 1 61.3 –142 12.9 P/2008 Y12 (SOHO) 2019–10–09 0.07 5.40 9.0 4.0 1 –36.0 19 14.0 68P/Klemola 2019–11–09 1.79 11.02 6.8 6.0 1 –11.1 –51 12.7 C/2018 N2 (ASASSN) 2019–11–11 3.12 6.0 4.0 1 39.7 –92 13.4 101P/Chernykh 2020–01–13 2.35 13.95 10.0 4.8 1 –3.0 –85 16.2 114P/Wiseman–Skiff 2020–01–14 1.58 6.68 11.5 6.0 1 25.9 –126 14.0 203P/Korlevic 2020–03–05 3.20 10.09 14.5 2.0 1 22.9 –142 18.9 P/2004 WR9 (LINEAR) 2020–04–01 1.95 15.24 14.5 4.0 1 15.3 –112 18.8 266P/Christensen 2020–04–19 2.33 6.64 12.5 4.0 1 22.4 –131 17.5 354P/LINEAR 2020–04–27 2.00 3.46 15.5 4.0 1 15.2 –103 19.7 155P/Shoemaker 2019–11–15 1.80 16.92 10.0 4.8 7 11.8 120 13.7 321P/SOHO 2020–01–17 0.05 3.77 20.0 4.0 17 –20.2 –1 7.1 112P/Urata–Niijima 2020–02–07 1.45 6.62 14.0 6.0 22 4.6 –63 17.5 228P/LINEAR 2020–03–10 3.44 8.53 14.5 2.0 Feb. 13 24.1 –169 19.1 124P/Mrkos 2020–04–26 1.65 6.05 13.1 6.0 Mar. 26 27.6 –138 16.0 P/2006 W1 (Gibbs) 2020–04–03 1.70 14.02 12.0 4.0 Apr. 1 –1.4 –11 16.4 210P/Christensen 2020–04–07 0.53 5.64 13.5 4.0 11 15.8 –23 11.3 87P/Bus 2020–05–09 2.10 6.38 10.0 6.0 12 –3.3 –169 15.1 P/2003 L1 (Scotti) 2020–07–09 5.02 17.41 9.5 4.0 26 –14.8 –176 19.5 91P/Russell 2020–11–09 2.61 7.68 7.5 6.0 28 –15.7 –141 15.8 246P/NEAT 2021–02–22 2.87 8.05 2.5 6.0 28 17.5 –139 12.1 P/2003 T12 (SOHO) 2020–05–06 0.59 4.16 17.0 4.0 May 6 12.6 6 15.8 P/2012 A3 (SOHO) 2020–05–06 0.59 4.16 17.0 4.0 6 12.6 6 15.8 278P/McNaught 2020–09–11 2.09 7.10 14.0 4.0 10 –6.9 –143 18.4 C/2017 T2 (PANSTARRS) 2020–05–04 1.61 1.9 5.3 12 75.1 –69 5.8 58P/Jackson–Neujmin 2020–05–24 1.38 8.25 11.0 6.0 29 8.0 38 14.6 84P/Giclas 2020–06–03 1.72 6.70 9.5 8.0 Jun. 14 13.7 31 16.2 296P/Garradd 2020–09–17 1.82 6.54 14.0 4.0 22 –22.3 –92 18.1 249P/LINEAR 2020–06–29 0.50 4.59 15.5 4.0 23 28.8 10 11.2 2P/Encke 2020–06–25 0.34 3.30 11.7 4.6 27 20.9 –16 6.6 P/2005 Y2 (McNaught) 2020–10–22 3.38 15.98 12.0 4.0 29 –19.8 –165 19.3 C/2017 K5 (PANSTARRS) 2020–03–22 7.68 7.0 4.0 30 –20.8 175 20.0 115P/Maury 2020–07–29 2.06 8.83 11.5 6.0 Jul. 19 –2.0 –159 16.4 304P/Ory 2020–08–11 1.26 5.61 16.5 4.0 Aug. 16 22.4 61 18.2 257P/Catalina 2020–09–11 2.14 7.29 11.5 4.0 16 15.6 –143 15.3 254P/McNaught 2020–09–28 3.14 9.96 11.0 4.0 31 –31.3 155 17.7 312P/NEAT 2020–09–25 1.98 6.45 16.0 4.0 Sep. 7 –19.1 –167 19.0 P/2005 T2 (Christensen) 2020–04–08 2.24 7.55 14.5 4.0 8 20.1 141 19.5 184P/Lovas 2020–10–26 1.70 7.38 13.5 4.0 13 –12.4 –149 15.5 88P/Howell 2020–09–26 1.35 5.47 6.0 6.0 18 –23.9 –67 8.7 317P/WISE 2020–09–26 1.27 5.11 17.5 4.0 23 –17.9 –39 19.9 P/2007 R2 (Gibbs) 2020–09–16 1.63 6.75 17.0 4.0 29 7.9 166 18.2 218P/LINEAR 2020–10–03 1.17 5.45 16.0 4.0 Oct. 4 –12.0 –24 18.2 156P/Russell–LINEAR 2020–11–17 1.33 6.45 13.0 6.0 Nov. 4 –12.1 –128 13.3 36P/Whipple 2020–05–31 3.02 8.39 8.5 6.0 5 9.0 159 17.6 P/2009 WX51 (Catalina) 2020–11–16 0.80 5.40 19.0 2.0 5 4.8 41 19.1 P/2012 SB6 (Lemmon) 2020–06–19 2.28 7.49 14.0 4.0 9 37.6 144 19.0 331P/Gibbs 2020–09–26 2.88 5.21 12.0 4.0 10 14.6 176 18.0 11P/Tempel–Swift–LINEAR 2020–11–25 1.39 5.99 17.0 4.0 10 19.5 –140 16.9 220P/McNaught 2020–12–10 1.55 5.50 15.0 4.0 14 –20.9 –53 18.4 162P/Siding Spring 2020–12–07 1.29 5.43 12.0 4.0 21 –23.4 –87 12.9 178P/Hug–Bell 2020–07–16 1.88 6.93 13.5 4.0 26 18.7 127 17.7 277P/LINEAR 2020–12–30 1.91 7.57 14.0 4.0 27 36.8 –150 16.9 311P/PANSTARRS 2020–10–06 1.94 3.24 17.0 4.0 Dec. 20 24.6 172 19.9 141P/Machholz 2020–12–14 0.80 5.33 12.0 12.0 21 –9.4 –55 8.4 P/2013 TL117 (Lemmon) 2020–12–24 1.12 6.85 17.5 4.0 21 22.1 95 16.4 P/2009 Q4 (Boattini) 2020–12–27 1.31 5.54 15.5 4.0 24 –4.6 –143 14.6 P/2007 VQ11 (Catalina) 2020–09–18 2.69 12.62 12.0 4.0 27 6.0 155 17.8 233P/La Sagra 2020–10–01 1.78 5.27 15.0 4.0 31 15.7 105 18.6 293P/Spacewatch 2020–12–19 2.12 6.95 14.5 4.0 31 24.2 136 18.3 10P/Tempel 2021–03–24 1.41 5.36 2.6 17.0 31 –18.6 13 14.0 BAA Handbook 2020 Comets 95 95 Jan 1 0:00 UT 137 Jan 16 180 160 Jan 31 213 0h 40m 234 214 257 251 Feb 15 252 Pisces 280 Mar 1 Mar 16 Mar 459 473 488 Mar 31 Mar 514 524 1h 20m 532 Apr 15 Apr M 74 660 661 665 670 Apr 30 Apr 672 673 678 684 676 680 691 697 695 693 COMETS 706 741 742 May 15 May 780 772 774 781 794 807 803 2h 00m 821 May 30 May 827 855 Dec 26 0:00 UT Dec 29P/SCHWASSMANN–WACHMANN 29P/SCHWASSMANN–WACHMANN Dec 11 Dec 864 871 877 Jun 14 Nov 26 Nov 924 Nov 11 Nov 930 Jun 29 972 Oct 27 Jul 14 990 1056 1030 1036 Oct 12 1024 Jul 29 1044 1046 Sep 27 Sep Aug 13 Aug 1070 1088 Sep 12 Sep 2h 40m Aug 28 Aug Aries 1134 1156 Jul 25, 2019 9:37 U128 Psc 2019 9:37 25, Jul + 5° +25° +20° +15° +10°

96 Comets BAA Handbook 2020 4454 4487 4504 4517 4520 4527 4536 4541 4546 12h 36m 4592 May 30 May 4593 4597 4599 4602 Jun 14 4632 4628 4626 4636 4642 4643 4653 May 15 May 4665 4666 4668 4671 4684 4690 4691 4697 4699 4705 4703 4720 4731 12h 48m 4739 4753 4776 4771 4772 4773 4775 Jun 29 0:00 UT 4777 4786 4799 4813 4818 Apr 30 Apr 4845 4843 4878 4888 4900 4879 4890 4904 4910 4915 4925 13h 00m 4928 4941 4942 4951 4958 Jan 1 0:00 UT 4981 4989 4999 4995 5015 COMETS Apr 15 Apr 13h 12m 88P/HOWELL Jan 16 Virgo 5147 13h 24m Mar 31 Mar 5183 5184 5203 Jan 31 5227 13h 36m Mar 16 Mar 5257 5258 Feb 15 Mar 1 Jul 26, 2019 20:44 U240 Vir 2019 20:44 26, Jul 13h 48m - 2° - 4° - 6° - 8° + 2° + 0°

BAA Handbook 2020 Comets 97 COMETS

C/2017 T2 (PANSTARRS)

Jun 29 0:00 UT M 63 Leo Minor Canes Venatici M 106 Bootes M 51

M 109 Ursa Major M 97 Jun 14 M 108 M 101

M 102

May 30 8h Lynx M 81 M 82 Ursa Minor

May 15

Camelopardalis Apr 30 Draco

Apr 15 +80°

Mar 31

+70° Cepheus Mar 16

Jan 1 0:00 UT Perseus Mar 1 Cassiopeia Jan 16 Feb 15 M 103 M 52 Jan 31 +60° 7000 M 39 4h Cygnus M 76 696 6992 M 34 +50° Lacerta

M 31110 M 32 +40°

2h 0h 22h

Jul 25, 2019 9:29 U1 Cep 98 Comets BAA Handbook 2020 METEORS This meteor diary has been considerably modified from that published in previous years to more closely follow the list of regular major and more reliable minor showers in the List of Established Meteor Showers published by the IAU Meteor Data Center (MDC). The data for many showers are derived from the Cameras for Allsky Meteor Surveillance project (CAMS) published by Jenniskens et al., 2016, Icarus, 266, 331. Due to space constraints in the Handbook this list does not include any minor showers where the peak Zenithal Hourly Rate (ZHR) is less than 5 meteors per hour. A number of the far southern hemisphere showers have also been excluded. Radiant data (UT, Alt.) and twilight data are for observers at the standard latitudes 52°N and 35°S, on the Greenwich meridian. Moonrise and moonset may be determined from the data on pages 29–33. All times are in UT. Normal limits are the dates between which the shower rates are normally greater than 25 per cent of the sporadic rate for the period.

Zenithal Hourly Rate (ZHR) is the probable hourly rate for a single experienced observer watching a clear sky with limiting magnitude 6.5 with the shower radiant at the zenith. To a first approximation, the observed hourly rate (OHR) is given by: OHR = ZHR sin α where α is the radiant elevation. Hence high rates cannot be expected if the radiant is low. Sky conditions can alter rates considerably and consequently observers should record the approximate naked eye limiting magnitude in the areas being watched during each observing session. The rates given are the maximum ones, and are only a guide in view of the inherent variability of showers. Twilight here is nautical, starting and ending when the Sun is 12° below the horizon. Radiant Daily Motion: Where available, these come from the IAU's List of Established Meteor Showers. Meteor radiants are not stationary because of the Earth’s motion around the Sun. They move about one degree of ecliptic longitude per day. The daily motions should be applied to determine the radiant positions at dates other than maximum. The positions of several shower radiants at maximum, radiant daily motion and geocentric velocities (Vg) have been revised following analysis of recent video meteor data by Alex Pratt using the NEMETODE multi–station video meteor dataset.. Special Notes for 2020: Bright moonlight has an adverse effect on meteor observing, and for about five days to either side of Full Moon, lunar glare swamps all but the brighter meteors. Fortunately, in 2020 very few of the major showers will be seriously hampered by moonlight. However, the complex of minor showers which peak in late July, now grouped together as part of the Antihelion Source, and the Alpha Capricornids, Southern Delta Aquarids and Piscis Austrinids will all suffer interference by moonlight this year. The Alpha Aurigids which peak in late August, the Camelopardalids which peak in early October and the Southern Taurids which peak in early November will also be affected. . There are, however, a great many excellent observing opportunities in 2020. The peaks of the April Lyrids, Northern Taurids, Leonids and Geminids all occur around the time of New Moon and the Orionids, Alpha Monocerotids and Ursids will all be largely unaffected by the First Quarter Moon. The Quadrantids also coincide with a First Quarter Moon and rates will be rising in the early morning hours with the radiant high in the pre- dawn sky. The maxima of the Perseids, Kappa Cygnids and September Epsilon Perseids all correspond with a Last Quarter Moon and for these showers visual observers may minimise the effects of moonlight where it is a problem by positioning themselves so the Moon is behind them and hidden behind a wall, tree or other suitable obstruction. It is hoped that observers will make a particular effort to take advantage of all observing opportunities during 2020, particularly the very favourable circumstances for the major showers occurring in the autumn period. As always, observations away from the major shower maxima and of year-round sporadic activity are every bit as important to the work of the Association’s Meteor Section as those obtained when high rates are anticipated.

BAA Handbook 2020 Meteor Diary 99 METEORS METEORS Radiant Position Latitude 52°N Latitude 35°S Shower Maximum Maximum Daily Motion Twilight Radiant Twilight Radiant Normal λ Local Time ☉ ZHR R.A. Dec. R.A. Dec. Vg Age of Name Limits of (2000.0) Date of Transit Date at Max. Moon Ends Begins UT Alt. Ends Begins UT Alt. Notes Activity ° hh mm (°) ° ° ° km/s h d h h h ° h h h ° Quadrantids Dec. 28 283.2 Jan. 4d 09h 80+ 15 18 (229) +49.5 +0.34 –0.25 40.7 8.5 Jan. 4 8 17.4 6.7 00 21 – – – – High activity, but with a rather narrow peak. Good –Jan. 12 03 41 in 2014. Bright events leave persistent trains. 06 67 Quite favourable. April Lyrids Apr. 032.0 Apr. 22d 00h 15 18 07 (272) +33.1 +0.84 –0.34 47.3 4.1 Apr. 22 29 20.6 3.4 21 17 18.4 5.6 01 09 Normally rather moderate activity, but fine displays 14–30 43 03 20 in 1803, 1922, 1982. 68 05 21 Very favourable. η–Aquarids Apr. 19– 046 May 6 40 22 32 (338) –0.8 +0.92 +0.37 65.7 7.7 May 6 13 21.1 2.8 02 03 18.2 5.7 02 05 Fine southern shower, poorly seen from the UK. May 28 03 12 04 29 Fast meteors, many with persistent trains. Good 06 48 in 2013. Daytime Arietids May 22 – 077 June 7 30? 02 56 (044) +24 +1.05 +0.28 41.1 9.9 Jun. 7 – – – 03 11 – – 06 10 Most active of the daytime showers. Good for radio July 2 09 60 10 31 observers. ZHR and radiant location uncertain. 15 26 14 06 Daytime May 20– 079 June 9 20? 04 16 (064) +27 ? ? 25.1 11.1 Jun. 9 – – – 04 12 – – 07 06 Peak overlaps with that of the Daytime Arietids. ζ–Perseids July 5 10 62 11 28 Good for radio observers. ZHR and radiant location 16 30 15 06 uncertain. June Bootids June 22 – 096 June 27 ? 14 52 (223) +48 ? ? 14.1 20.7 Jun. 27 6 22.5 1.6 22 74 – – – – Unexpected outburst with ZHR~100 m/h in 1998 July 2 00 56 June 27 after a quiescent period of several decades. 02 40 Quite favourable. α–Capricornids July 3 – 127 July 30 5 20 28 (307) –09 +0.97 +0.24 23.0 0.0 Jul. 30 10 21.5 2.6 21 18 18.2 6.0 20 31 A good proportion of bright, slow–moving Aug. 15 00 28 00 64 colourful meteors. 03 17 04 29 Rather favourable. Southern July 12 – 128 Jul. 31 20 22 44 (341) –16 +0.95 +0.38 41.3 2.3 Jul. 31 11 21.5 2.6 23 10 18.2 6.0 21 20 Fine southern shower with double radiant. S. δ–Aquarids Aug. 23 01 20 01 65 component is more active. Rich in faint meteors. 03 21 05 48 Unfavourable. Piscis Austrinids Jul. 15 – 136 Aug 8 5 23 32 (353) –21 +0.94 +0.40 43.8 2.5 Aug. 8 19 21.1 3.0 23 05 18.2 6.0 21 20 Southern shower in need of observation. Date of Aug. 10 01 15 01 67 maximum and radiant location uncertain. 03 17 05 53 Unfavourable. Perseids July 17– 140.0 Aug. 12d 13h 80+ 03 11 (048) +58.0 +1.34 +0.25 58.6 5.9 Aug. 12 22 20.9 3.2 21 27 – – – – Rich & fast meteors. High proportion of bright Aug. 24 00 43 events leaving persistent trains. 03 66 Moonlight interferes. κ–Cygnids Aug. 3–25 141 Aug. 13 5 18 32 (278) +53 +0.40 +0.50 20.9 21.1 Aug. 13 23 20.9 3.2 21 89 – – – – Slow meteors with occasional bright fireballs. Date 00 64 of max.may be as late as August 18. 03 39 Quite favourable. α–Aurigids Aug. 28 – 158 Aug. 31 5 06 04 (091) +39 +1.24 –0.01 65.6 7.5 Aug. 31 2 20.1 3.9 00 19 18.6 5.4 04 02 Short–lived outbursts in activity in 1994 and more Sep. 5 02 35 05 09 recently in 2007. 04 53 Unfavourable. September Sep. 5–21 167 Sep. 9 5 03 16 (049) +40 +1.17 +0.26 64.3 4.1 Sep. 9 21 19.7 4.2 20 16 18.7 5.2 01 04 Stronger than usual display seen in 2013. ε–Perseids 00 48 03 14 04 78 05 14 Moonlight interferes. October Oct. 5–6 193 Oct. 6 5 11 04 (166) +79 ? ? 46.6 10.2 Oct. 6 18 18.7 4.9 20 42 – – – – Significant activity reported by video observers in Camelopardalids 00 42 2005 and 2006. outburst in 2016. 04 50 Rather unfavourable. Orionids Oct. 2 – 209 Oct. 22 20 06 24 (096) +15.7 +0.71 +0.07 65.0 4.5 Oct. 22 6 18.1 5.4 23 18 19.3 4.2 00 10 Fast meteors, many with persistent trains. Flat Nov. 7 02 44 02 29 maximum, with several sub–peaks. Good in 2007. 05 53 04 39 Very favourable. Southern Taurids Sep. 10 – 223 Nov. 5 5 03 33 (053) +12.9 +0.74 +0.13 26.1 0.6 Nov. 5 19 18.5 5.1 20 24 19.1 4.5 21 21 Southern branch of the Taurid complex. Slow Nov. 20 00 50 00 41 meteors. Dbl. radiant. Broad peak λ☼ =220°–230°. 04 33 03 31 Unfavourable. Northern Taurids Oct. 20– 230 Nov. 12 5 03 57 (059) +22.3 +0.70 +0.15 28.7 0.6 Nov. 12 26 17.5 5.9 20 31 19.7 3.8 21 14 Northern branch of the Taurid complex. Slow Dec. 10 00 60 00 32 meteors. 04 41 03 23 Very favourable. Leonids Nov. 6–30 236.0 Nov 18d 05h 15 10 17 (154) +21.4 +0.59 –0.29 69.7 6.6 Nov. 18 3 17.4 6.1 00 12 19.8 3.7 02 05 Very fast meteors, many with persistent trains. 03 40 03 15 Enhanced activity unlikely until the late 2020s. 06 59 04 23 Very favourable. α–Monocerotids Nov. 239 Nov. 21 ? 07 48 (117) +0.9 +0.95 –0.09 63.0 3.8 Nov. 21 6 17.4 6.1 00 20 19.9 3.6 23 15 Occasional very short–lived outbursts in activity, 15–25 03 38 01 37 most recently in 1995 and possibly in 2016. 06 32 03 52 Very favourable. Geminids Dec. 4–17 262.0 Dec. 13d 20h 100+ 07 34 (114) +32.3 +0.97 –0.23 33.6 2.1 Dec. 13 28 17.2 6.6 20 25 20.3 3.6 23 10 Richest of the annual showers, with slow meteors 00 60 01 21 and a good proportion of bright events. 04 61 03 21 Very favourable. Ursids Dec. 271 Dec. 22 10 14 40 (220) +75.4 +0.05 –0.31 32.9 8.7 Dec. 23 7 17.3 6.7 20 38 – – – – Under–observed shower which has produced 17–26 01 44 outbursts in 1945, 1982, 1986 and in 2014. 06 62 Quite favourable.

100 Meteor Diary BAA Handbook 2020 METEORS METEORS Radiant Position Latitude 52°N Latitude 35°S Shower Maximum Maximum Daily Motion Twilight Radiant Twilight Radiant Normal λ Local Time ☉ ZHR R.A. Dec. R.A. Dec. Vg Age of Name Limits of (2000.0) Date of Transit Date at Max. Moon Ends Begins UT Alt. Ends Begins UT Alt. Notes Activity ° hh mm (°) ° ° ° km/s h d h h h ° h h h ° Quadrantids Dec. 28 283.2 Jan. 4d 09h 80+ 15 18 (229) +49.5 +0.34 –0.25 40.7 8.5 Jan. 4 8 17.4 6.7 00 21 – – – – High activity, but with a rather narrow peak. Good –Jan. 12 03 41 in 2014. Bright events leave persistent trains. 06 67 Quite favourable. April Lyrids Apr. 032.0 Apr. 22d 00h 15 18 07 (272) +33.1 +0.84 –0.34 47.3 4.1 Apr. 22 29 20.6 3.4 21 17 18.4 5.6 01 09 Normally rather moderate activity, but fine displays 14–30 43 03 20 in 1803, 1922, 1982. 68 05 21 Very favourable. η–Aquarids Apr. 19– 046 May 6 40 22 32 (338) –0.8 +0.92 +0.37 65.7 7.7 May 6 13 21.1 2.8 02 03 18.2 5.7 02 05 Fine southern shower, poorly seen from the UK. May 28 03 12 04 29 Fast meteors, many with persistent trains. Good 06 48 in 2013. Daytime Arietids May 22 – 077 June 7 30? 02 56 (044) +24 +1.05 +0.28 41.1 9.9 Jun. 7 – – – 03 11 – – 06 10 Most active of the daytime showers. Good for radio July 2 09 60 10 31 observers. ZHR and radiant location uncertain. 15 26 14 06 Daytime May 20– 079 June 9 20? 04 16 (064) +27 ? ? 25.1 11.1 Jun. 9 – – – 04 12 – – 07 06 Peak overlaps with that of the Daytime Arietids. ζ–Perseids July 5 10 62 11 28 Good for radio observers. ZHR and radiant location 16 30 15 06 uncertain. June Bootids June 22 – 096 June 27 ? 14 52 (223) +48 ? ? 14.1 20.7 Jun. 27 6 22.5 1.6 22 74 – – – – Unexpected outburst with ZHR~100 m/h in 1998 July 2 00 56 June 27 after a quiescent period of several decades. 02 40 Quite favourable. α–Capricornids July 3 – 127 July 30 5 20 28 (307) –09 +0.97 +0.24 23.0 0.0 Jul. 30 10 21.5 2.6 21 18 18.2 6.0 20 31 A good proportion of bright, slow–moving Aug. 15 00 28 00 64 colourful meteors. 03 17 04 29 Rather favourable. Southern July 12 – 128 Jul. 31 20 22 44 (341) –16 +0.95 +0.38 41.3 2.3 Jul. 31 11 21.5 2.6 23 10 18.2 6.0 21 20 Fine southern shower with double radiant. S. δ–Aquarids Aug. 23 01 20 01 65 component is more active. Rich in faint meteors. 03 21 05 48 Unfavourable. Piscis Austrinids Jul. 15 – 136 Aug 8 5 23 32 (353) –21 +0.94 +0.40 43.8 2.5 Aug. 8 19 21.1 3.0 23 05 18.2 6.0 21 20 Southern shower in need of observation. Date of Aug. 10 01 15 01 67 maximum and radiant location uncertain. 03 17 05 53 Unfavourable. Perseids July 17– 140.0 Aug. 12d 13h 80+ 03 11 (048) +58.0 +1.34 +0.25 58.6 5.9 Aug. 12 22 20.9 3.2 21 27 – – – – Rich & fast meteors. High proportion of bright Aug. 24 00 43 events leaving persistent trains. 03 66 Moonlight interferes. κ–Cygnids Aug. 3–25 141 Aug. 13 5 18 32 (278) +53 +0.40 +0.50 20.9 21.1 Aug. 13 23 20.9 3.2 21 89 – – – – Slow meteors with occasional bright fireballs. Date 00 64 of max.may be as late as August 18. 03 39 Quite favourable. α–Aurigids Aug. 28 – 158 Aug. 31 5 06 04 (091) +39 +1.24 –0.01 65.6 7.5 Aug. 31 2 20.1 3.9 00 19 18.6 5.4 04 02 Short–lived outbursts in activity in 1994 and more Sep. 5 02 35 05 09 recently in 2007. 04 53 Unfavourable. September Sep. 5–21 167 Sep. 9 5 03 16 (049) +40 +1.17 +0.26 64.3 4.1 Sep. 9 21 19.7 4.2 20 16 18.7 5.2 01 04 Stronger than usual display seen in 2013. ε–Perseids 00 48 03 14 04 78 05 14 Moonlight interferes. October Oct. 5–6 193 Oct. 6 5 11 04 (166) +79 ? ? 46.6 10.2 Oct. 6 18 18.7 4.9 20 42 – – – – Significant activity reported by video observers in Camelopardalids 00 42 2005 and 2006. outburst in 2016. 04 50 Rather unfavourable. Orionids Oct. 2 – 209 Oct. 22 20 06 24 (096) +15.7 +0.71 +0.07 65.0 4.5 Oct. 22 6 18.1 5.4 23 18 19.3 4.2 00 10 Fast meteors, many with persistent trains. Flat Nov. 7 02 44 02 29 maximum, with several sub–peaks. Good in 2007. 05 53 04 39 Very favourable. Southern Taurids Sep. 10 – 223 Nov. 5 5 03 33 (053) +12.9 +0.74 +0.13 26.1 0.6 Nov. 5 19 18.5 5.1 20 24 19.1 4.5 21 21 Southern branch of the Taurid complex. Slow Nov. 20 00 50 00 41 meteors. Dbl. radiant. Broad peak λ☼ =220°–230°. 04 33 03 31 Unfavourable. Northern Taurids Oct. 20– 230 Nov. 12 5 03 57 (059) +22.3 +0.70 +0.15 28.7 0.6 Nov. 12 26 17.5 5.9 20 31 19.7 3.8 21 14 Northern branch of the Taurid complex. Slow Dec. 10 00 60 00 32 meteors. 04 41 03 23 Very favourable. Leonids Nov. 6–30 236.0 Nov 18d 05h 15 10 17 (154) +21.4 +0.59 –0.29 69.7 6.6 Nov. 18 3 17.4 6.1 00 12 19.8 3.7 02 05 Very fast meteors, many with persistent trains. 03 40 03 15 Enhanced activity unlikely until the late 2020s. 06 59 04 23 Very favourable. α–Monocerotids Nov. 239 Nov. 21 ? 07 48 (117) +0.9 +0.95 –0.09 63.0 3.8 Nov. 21 6 17.4 6.1 00 20 19.9 3.6 23 15 Occasional very short–lived outbursts in activity, 15–25 03 38 01 37 most recently in 1995 and possibly in 2016. 06 32 03 52 Very favourable. Geminids Dec. 4–17 262.0 Dec. 13d 20h 100+ 07 34 (114) +32.3 +0.97 –0.23 33.6 2.1 Dec. 13 28 17.2 6.6 20 25 20.3 3.6 23 10 Richest of the annual showers, with slow meteors 00 60 01 21 and a good proportion of bright events. 04 61 03 21 Very favourable. Ursids Dec. 271 Dec. 22 10 14 40 (220) +75.4 +0.05 –0.31 32.9 8.7 Dec. 23 7 17.3 6.7 20 38 – – – – Under–observed shower which has produced 17–26 01 44 outbursts in 1945, 1982, 1986 and in 2014. 06 62 Quite favourable.

BAA Handbook 2020 Meteor Diary 101 VARIABLE STARS Heliocentric Times of Primary Minima

RZ Cassiopeiae: Magnitude 6.2 to 7.7, Duration 4.8 hours d h d h d h d h d h d h Jan. 1 6.1 Feb. 1 8.0 Mar. 1 0.4* Apr. 1 2.3* May 2 4.1 Jun. 1 1.3 2 10.8 2 12.7 2 5.1 2 7.0 3 8.8 2 6.0 3 15.5 3 17.3 3 9.8 3 11.6 4 13.5 3 10.6 4 20.2* 4 22.0* 4 14.5 4 16.3 5 18.2 4 15.3 6 0.9* 6 2.7* 5 19.2 5 21.0 6 22.9 5 20.0 7 5.6* 7 7.4 6 23.9* 7 1.7* 8 3.5 7 0.7 8 10.3 8 12.1 8 4.6 8 6.4 9 8.2 8 5.4 9 14.9 9 16.8 9 9.2 9 11.1 10 12.9 9 10.1 10 19.6 10 21.5* 10 13.9 10 15.8 11 17.6 10 14.8 12 0.3* 12 2.1* 11 18.6 11 20.5 12 22.3 11 19.4 13 5.0* 13 6.8 12 23.3* 13 1.1* 14 3.0 13 0.1 14 9.7 14 11.5 14 4.0 14 5.8 15 7.7 14 4.8 15 14.4 15 16.2 15 8.7 15 10.5 16 12.3 15 9.5 16 19.1 16 20.9* 16 13.4 16 15.2 17 17.0 16 14.2 17 23.7* 18 1.6* 17 18.0 17 19.9 18 21.7 17 18.9 19 4.4* 19 6.3 18 22.7* 19 0.6* 20 2.4 18 23.6 20 9.1 20 10.9 20 3.4 20 5.3 21 7.1 20 4.2 21 13.8 21 15.6 21 8.1 21 9.9 22 11.8 21 8.9 22 18.5 22 20.3 22 12.8 22 14.6 23 16.5 22 13.6 23 23.2* 24 1.0* 23 14.5 23 19.3 24 21.1 23 18.3 25 3.9* 25 5.7 24 22.3* 24 0.0* 26 1.8 24 23.0 26 8.5 26 10.4 26 2.8* 26 4.7 27 6.5 26 3.7 27 13.2 27 15.1 27 7.5 27 9.4 28 11.2 27 8.4 28 17.9 28 19.8 28 12.2 28 14.1 29 15.9 28 13.0 29 22.6* 29 16.9 29 18.7 30 20.6 29 17.7 31 3.3* 30 21.6* 30 23.4 30 22.4

Jul. 2 3.1 Aug. 1 0.3* Sep. 1 2.1* Oct. 2 3.9 Nov. 1 1.1* Dec. 2 2.9* 3 7.8 2 4.9 2 6.8 3 8.6 2 5.8 3 7.6 4 12.5 3 9.6 3 11.5 4 13.3 3 10.5 4 12.3 5 17.2 4 14.3 4 16.1 5 18.0 4 15.1 5 17.0 6 21.8 5 19.0 5 20.8 6 22.7* 5 19.8 6 21.7* 8 2.5 6 23.7* 7 1.5* 8 3.4* 7 0.5* 8 2.3* 9 7.2 8 4.4 8 6.2 9 8.0 8 5.2 9 7.0 10 11.9 9 9.1 9 10.9 10 12.7 9 9.9 10 11.7 11 16.6 10 13.7 10 15.6 11 17.4 10 14.6 11 16.4 12 21.3 11 18.4 11 20.3 12 22.1* 11 19.3 12 21.1* 14 2.0 12 23.1* 13 1.0* 14 2.8* 12 23.9* 14 1.8* 15 6.6 14 3.8 14 5.6 15 7.5 14 4.6 15 6.5 16 11.3 15 8.5 15 10.3 16 12.2 15 9.3 16 11.1 17 16.0 16 13.2 16 15.0 17 16.8 16 14.0 17 15.8 18 20.7 17 17.9 17 19.7 18 21.5* 17 18.7 18 20.5* 20 1.4 18 22.5* 19 0.4* 20 2.2* 18 23.4* 20 1.2* 21 6.1 20 3.2 20 5.1 21 6.9 20 4.1* 21 5.9 22 10.8 21 7.9 21 9.8 22 11.6 21 8.7 22 10.6 23 15.4 22 12.6 22 14.4 23 16.3 22 13.4 23 15.3 24 20.1 23 17.3 23 19.1 24 21.0 23 18.1 24 20.0 26 0.8 24 22.0 24 23.8* 26 1.6* 24 22.8* 26 0.6* 27 5.5 26 2.7 26 4.5 27 6.3 26 3.7* 27 5.3 28 10.2 27 7.3 27 9.2 28 11.0 27 8.2 28 10.0 29 14.9 28 12.0 28 13.9 29 15.7 28 12.9 29 14.7 30 19.6 29 16.7 29 18.6 30 20.4 29 17.5 30 19.4 30 21.4 30 23.2* 30 22.2*

102 Variable Stars BAA Handbook 2020 VARIABLE STARS

b Persei (Algol): Magnitude 2.1 to 3.4, Duration 9.6 hours d h d h d h d h d h d h Jan. 2 19.5 Feb. 3 8.5 Mar. 3 0.6* Apr. 3 13.6 May 2 5.8 Jun. 2 18.7 5 16.3 6 5.3 5 21.4* 6 10.4 5 2.6 5 15.5 8 13.1 9 2.1* 8 18.3 9 7.2 7 23.4 8 12.4 11 10.0 11 22.9* 11 15.1 12 4.0 10 20.2 11 9.2 14 6.8 14 19.7 14 11.9 15 0.9 13 17.0 14 6.0 17 3.8* 17 16.6 17 8.7 17 21.7 16 13.8 17 2.8 20 0.4* 20 13.4 20 5.5 20 18.5 19 10.7 19 23.6 22 21.2* 23 10.2 23 2.3* 23 15.3 22 7.5 22 20.4 25 18.0 26 7.0 25 23.2* 26 12.1 25 4.3 25 17.3 28 14.8 29 3.8* 28 20.0 29 8.9 28 1.1 28 14.1 31 11.7 31 16.8 30 21.9

Jul. 1 10.9 Aug. 1 23.9 Sep. 2 12.8 Oct. 1 5.0 Nov. 1 18.0 Dec. 3 6.9 4 7.7 4 20.7 5 9.6 4 1.8* 4 14.8 6 3.7* 7 4.5 7 17.5 8 6.5 6 22.6* 7 11.6 9 0.6* 10 1.3 10 14.3 11 3.3 9 19.4 10 8.4 11 21.4* 12 22.1 13 11.1 14 0.1* 12 16.2 13 5.2 14 18.2 15 19.0 16 7.9 16 20.9 15 13.1 16 2.0* 17 15.0 18 15.8 19 4.7 19 17.7 18 9.9 18 22.8* 20 11.8 21 12.6 22 1.6* 22 14.5 21 6.7 21 19.7 23 8.6 24 9.4 24 22.4 25 11.4 24 3.5* 24 16.5 26 5.5 27 6.2 27 19.2 28 8.2 27 0.3* 27 13.3 29 2.3* 30 3.0 30 16.0 29 21.1 30 10.1 31 23.1*

RS Canum Venaticorum 7.9 to 9.1, Duration 13 hours

d h d h d h d h d h d h Jan. 4 2.2* Feb. 1 21.1 Mar. 1 15.9 Apr. 4 6.0 May 3 0.8 Jun. 5 14.8 8 21.3 6 16.2 6 11.1 9 1.1 7 20.0 10 10.0 13 16.5 11 11.4 11 6.2 13 20.2 12 15.1 15 5.1 18 11.6 16 6.5 16 1.4* 18 15.4 17 10.3 20 0.3 23 6.8 21 1.6* 20 20.5 23 10.5 22 5.4 24 19.4 28 1.9* 25 20.8 25 15.7 28 5.7 27 0.5 29 14.6 30 10.8 31 19.7

Jul. 4 9.7 Aug. 2 4.6 Sep. 4 18.6 Oct. 3 13.5 Nov. 1 8.3 Dec. 4 22.3* 9 4.8 6 23.7 9 13.7 8 8.6 6 3.5 9 17.5 14 0.0 11 18.9 14 8.9 13 3.7 10 22.6 14 12.6 18 19.1 16 14.0 19 4.0 17 22.9 15 17.8 19 7.8 23 14.3 21 9.2 23 23.2 22 18.0 20 12.9 24 2.9* 28 9.4 26 4.3 28 18.3 27 13.2 25 8.0 28 22.1* 30 23.4 30 3.2*

Minima marked with an asterisk (*) are favourable from the British Isles, taking into account the altitude of the variable and the distance of the Sun below the horizon (based on longitude 0° and latitude 52° N).

Heliocentric times must be UTC corrected for the light–time to the Sun. To calculate this, use the program on the Computing Section website. http://britastro.org/computing/applets_dt.html BAA Handbook 2020 Variable Stars 103 MIRA STARS Approximate dates of maxima and minima for Mira stars on the programme of the BAA Variable Star Section, together with (usually) the mean visual range(P), and fraction of the period taken in rising from minimum (m) to maximum (M) for each star. The predictions, which are subject to inevitable uncertainty, use data partly from the BAA and partly from the American Association of Variable Star Observers.

Star Range Period Max–Min Date of Max. Date of Min. Max Min Period d R And 6.9 14.3 409 0.38 Oct. May W And 7.4 13.7 396 0.42 Apr./May Dec./Jan. 2021 RW And 8.7 14.8 430 0.36 May – R Aqr 6.5 10.3 387 0.42 Jul. Jan./Feb. R Aql 6.1 11.5 284 0.42 Feb. & Nov./Dec. Jul./Aug. UV Aur* 7.4 10.6 394 0.50 Oct./Nov. Apr./May V Cam 9.9 15.4 522 0.31 Jun./Jul. Jan. X Cam 8.1 12.6 144 0.49 Jan./Feb. & Jun./Jul. Apr. & Aug./Sep. & Nov. SU Cnc* 10.5 [15.4 187 0.43 Feb./Mar. & Aug./Sep. Jun. & Dec./Jan 2021 U CVn 9.9 14.6 346 0.37 Jun. Jan./Feb. RT CVn* 9.9 [15.0 254 0.45 Jun./Jul. Mar. S Cas 9.7 14.8 612 0.43 Oct./Nov. Jan./Feb. T Cas 7.9 11.9 445 0.56 Oct./Nov. Apr. ο Cet 3.4 9.3 332 0.38 Sep./Oct. May/Jun. R Com 8.5 14.2 363 0.38 Jul./Aug. Mar. S CrB 7.3 12.9 360 0.35 Jul./Aug. Mar./Apr. V CrB 7.5 11.0 358 0.41 Sep. Apr./May W CrB 8.5 13.5 238 0.45 Jun. Feb./Mar. & Oct/Nov R Cyg 7.5 13.9 426 0.35 Oct/Nov. May/Jun. S Cyg 10.3 16.0 323 0.50 May Oct./Nov. V Cyg 9.1 12.8 421 0.46 Aug./Sep. Feb. χ Cyg 5.2 13.4 408 0.41 Jan. Sep. T Dra 9.6 12.3 422 0.44 Nov./Dec. May/Jun. RU Her 8.0 13.7 485 0.43 May – SS Her 9.2 12.4 107 0.48 Feb./Mar. & Jun. Jan. & Apr. & Sep./Oct. & Jul./Aug. R Hya 4.5 9.5 389 0.49 Oct./Nov. Apr./May SU Lac* 10.3 [15.0 302 0.40 Jun./Jul. Feb./Mar. RS Leo* 9.7 [15.5 208 0.31 Mar. & Oct. Jan. & Jul./Aug. W Lyn 9.9 ≈15.0 295 0.40 Sep./Oct. May/Jun. X Lyn 10.2 ≈15.0 321 0.40 Mar./Apr. – X Oph 6.8 8.8 329 0.53 Jan. & Nov./Dec. May/Jun. U Ori 6.3 12.0 368 0.38 Apr./May Dec. R Ser 6.9 13.4 356 0.41 May/Jun. Dec./Jan. 2021 T UMa 7.7 12.9 257 0.41 Mar./Apr. & Dec. Aug./Sep.

* Extreme range is given [ Fainter than ≈ Approximately

104 Variable Stars BAA Handbook 2020 VARIABLE STAR OF THE YEAR

Variable Star of the Year – SV Sagittae

SV Sagittae (SV Sge) has been known to astronomers since its variability was discovered photo- graphically by Russian astronomer Vladimir Albitsky in 1928. He published twenty observations from 1904 to 1926, revealing a rise in brightness from 13.9 to 11.6 during 1926. He didn’t, however, speculate on the type of variable star SV Sge might be, due to a lack of observations. In 1938 SV Sge was included in a list of suspected RCB type variables by Celia Payne and Sergei Gaposchkin – with some reservations – and finally included in the third supplement of the General Catalogue of Variable Stars (GCVS) as type RCB in 1976. [1] RCB stars (or R Coronae Borealis Stars) are F–G type supergiants and are some of the rarest types of star known to astronomers, wherein they contain very little or no hydrogen whatsoever (99.9% of stars do). Carbon and cyanogen are the dominant lines in the spectrum, along with helium and various metals. SV Sge itself is a rare carbon RCB star of spectral type C. Only 126 confirmed RCB stars are listed in VSX [2], of which 23 of them are type C. Fifty RCB stars can be found in Sagit- tarius (33) and Ophiuchus (17) alone! The name RCB derives from the prototype star in the constellation Corona Borealis – R CrB, the first to be recognised and also the brightest in its class (seeVSOTY 2003) [3]. The light curves for RCB stars are instantly recognisable, as long periods of inactivity are inter- rupted with sharp declines in brightness (sometimes by as much as ten magnitudes) followed by a much slower rise to maximum brightness, which on occasions can take many years to complete. These sudden fades are thought to be caused by ‘clouds’ of dusty carbon ejected at random which reduces the light from the star if the observer happens to lie in the line of sight. After time, these clouds thin out and disappear, resulting in a return to maximum brightness of the star. The fades and recoveries are totally unpredictable in nature, thus making the RCB stars wonderful targets for amateur variable star observers. SV Sge can be found at 19h 08m 11.8” +17d 37’ 42” (2000.0) and be seen at a maximum brightness varying between magnitudes 10 and 11. At minimum, SV Sge can fade by nearly seven magnitudes to below magnitude 17, but the depth of fade can vary quite a bit (see accompanying light curve). The field can be easily located and is a simple 3.8–degree north-east star hop from the naked-eye star zeta Aql (mag. 2.9) for those who use manual telescopes. The field is a rich star area, and care should be taken to correctly identify the variable when observing for the first time. That area of sky is also heavily reddened, contributing to the red appearance of SV Sge itself, and resulting in reddened stars with a high B–V value being used in the comparison star sequence. The BAAVSS have produced two finder charts with sequences – 30 arc minute and 10 arc minute fields – to help identify and measure the brightness of SV Sge. The BAAVSS has been observing SV Sge since 1988, and in that time have observed nine fades in all. The most recent period of activity started in 2018 September, after which SV Sge reached an historical low level of brightness in 2018 December, when it faded to V magnitude of 17.14. This extreme low state followed a period of 13 years at maximum brightness and was detected by BAAVSS observers who continued to monitor the star to its new record minimum despite its poor sky location in the winter of 2018–19. The star has been slowly recovering during 2019, and observers are encouraged to monitor closely for future fading episodes. Notes: [1] SV Sagittae 1899–1979, J.F. Manella, J. AAVSO, 9(1), 18-19 (1980). [2] VSX https://www.aavso.org/vsx/ [3] BAA Handbook 2003 http://www.britastro.org/vss/VSOTY_2003_rcrb.pdf [4] BAAVSS charts for SV Sge http://www.britastro.org/vss/xchartcat/sv–sge_.html

BAA Handbook 2020 Variable Stars 105 SV SAGITTAE LIGHT CURVE LIGHT SAGITTAE SV

106 Variable Stars BAA Handbook 2020 SV SAGITTAE FINDER CHART

BAA Handbook 2020 Variable Stars 107 EPHEMERIDES OF VISUAL BINARY STARS Inspection of the two–point ephemeris will indicate whether a pair is closing, relatively static, or opening up, and whether motion is direct or retrograde. A fast–mover of long period is probably near periastron, while a slow–mover of short period is likely to be near apastron. The orbital elements employed for the computation are those published in the Sixth Catalog of Orbits of Visual Binary Stars, by Stephen J. Williams, William I. Hartkopf and Brian D. Mason, U.S. Naval Observatory: https://ad.usno.navy.mil/wds/orb6.html

2000.0 2020.0 2021.0 Star Name ADS RA Dec. Mags. Period PA Dist. PA Dist. h m ° ′ y ° ″ ° ″ 85 Peg 17175 0 02.2 +27 05 5.8 8.9 26 123.0 0.75 132.7 0.78 OΣ 4 221 0 16.7 +36 29 7.9 9.8 109 333.5 0.17 322.5 0.18 λ Cas 434 0 31.8 +54 31 5.3 5.6 246 252.6 0.11 263.9 0.10 β 395 520 0 37.3 –24 46 6.6 6.2 25 130.8 0.33 154.6 0.17 η Cas 671 0 49.1 +57 49 3.5 7.3 479 326.4 13.41 327.6 13.43

36 And 755 0 55.0 +23 38 6.1 6.5 168 334.6 1.18 335.6 1.19 Howe 4 1223 1 33.7 –12 13 9.2 9.3 142 329.4 0.86 329.1 0.86 Dunlop 5 … 1 39.8 –56 12 5.7 5.9 475 185.9 11.63 185.6 11.63 Σ 186 1538 1 55.9 +01 51 6.7 6.8 166 74.8 0.64 75.8 0.62 α Psc 1615 2 02.0 +02 46 4.1 5.1 3267 260.2 1.84 259.5 1.84

10 Ari 1631 2 03.7 +25 56 5.8 7.8 325 349.0 1.57 349.3 1.58 Σ 228 1709 2 14.0 +47 29 6.5 7.2 145 308.9 0.59 311.4 0.56 h 3494 .. 2 19.8 –35 27 9.0 9.1 475 240.5 2.32 240.0 2.33 ι Cas AB 1860 2 29.1 +67 24 4.6 6.9 620 227.3 2.64 226.7 2.64 Σ 305 2122 2 47.5 +19 22 7.5 8.2 531 306.8 3.59 306.7 3.59

α For 2402 3 12.1 –28 59 3.9 7.1 269 300.7 5.45 300.7 5.47 Σ 367 2416 3 14.0 +00 44 8.1 8.1 420 129.6 1.27 129.2 1.27 7 Tau 2616 3 34.4 +24 28 6.6 6.8 522 350.2 0.77 349.7 0.77 OΣ 65 2799 3 50.3 +25 35 5.7 6.5 61 202.7 0.55 202.9 0.57 40 Eri BC 3093 4 15.3 –07 39 9.5 11.2 230 330.5 8.09 330.0 8.02

OΣ 77 AB 3082 4 15.9 +31 42 8.0 8.2 188 306.6 0.49 307.8 0.47 Hu 445 3614 5 01.7 +20 50 9.3 8.4 166 157.4 0.34 157.7 0.33 14 Ori 3711 5 07.9 +08 30 5.7 6.6 197 283.1 0.98 281.5 0.99 η Gem 4841 6 14.9 +22 30 3.5 6.1 474 251.6 1.61 251.2 1.61 OΣ 149 5234 6 36.4 +27 17 7.1 8.9 119 277.6 0.73 276.4 0.73

12 Lyn AB 5400 6 46.2 +59 27 5.4 6.0 908 65.1 1.92 64.1 1.92 14 Lyn 5514 6 53.1 +59 27 6.0 6.5 316 357.9 0.32 359.3 0.32 α Gem 6175 7 34.6 +31 53 1.9 2.9 460 52.2 5.38 51.6 5.44 9 Pup 6420 7 51.8 –13 54 5.6 6.4 23 307.2 0.39 311.6 0.35 ζ Cnc AB 6650 8 12.2 +17 39 5.3 6.3 60 5.2 1.13 2.0 1.14 ζ Cnc AB–C 6650 8 12.2 +17 39 4.9 5.8 1115 64.1 5.93 63.6 5.93 β 208 6914 8 39.1 –22 40 5.3 6.8 123 68.2 0.45 75.2 0.35 I 314 .. 8 39.4 –36 36 6.4 7.9 67 240.9 0.89 240.6 0.90 δ Vel .. 8 44.7 –54 43 1.9 5.5 147 198.7 0.77 195.1 0.86 ε Hya AB–C 6993 8 46.8 +06 25 3.4 5.0 15 271.7 0.18 314.6 0.09

Σ 1338 7307 9 21.0 +38 11 6.7 7.0 303 321.9 1.00 323.6 1.00 ω Leo 7390 9 28.5 +09 03 5.6 7.2 118 114.7 0.89 115.6 0.90 γ Sex 7555 9 52.5 –08 06 5.4 6.4 78 36.1 0.48 34.3 0.47 γ Leo 7724 10 20.0 +19 50 2.3 3.6 554 126.6 4.73 126.6 4.73 β 411 7846 10 36.1 –26 41 6.6 7.7 159 302.9 1.33 302.5 1.33

108 Double Stars BAA Handbook 2020 EPHEMERIDES OF VISUAL BINARY STARS 2000.0 2020.0 2021.0 Star Name ADS RA Dec. Mags. Period PA Dist. PA Dist. h m ° ′ y ° ″ ° ″

ξ UMa AB 8119 11 18.2 +31 32 4.3 4.8 60 152.5 2.10 148.7 2.29 ι Leo 8148 11 23.9 +10 32 4.0 6.7 186 92.0 2.20 91.2 2.25 BrsO 5 .. 11 24.7 –61 39 7.6 8.7 399 249.2 7.67 249.4 7.75 OΣ 235 8197 11 32.3 +61 05 5.6 7.5 73 46.4 0.95 48.5 0.97 Σ 1639 8539 12 24.4 +25 35 6.7 7.8 575 322.7 1.85 322.6 1.87

β 28 8573 12 30.1 –13 24 6.4 9.5 151 349.1 2.14 349.7 2.14 γ Cen .. 12 41.5 –48 58 2.8 2.8 84 28.5 0.39 24.3 0.48 γ Vir 8630 12 41.7 –01 27 3.4 3.5 169 357.4 2.93 356.2 3.05 35 Com 8695 12 53.3 +21 15 5.1 7.0 539 201.7 1.19 202.5 1.19 I 83 .. 12 56.7 –47 41 7.3 7.6 173 237.2 0.86 237.5 0.86

78 UMa 8739 13 00.7 +56 22 5.0 7.8 105 151.0 0.59 160.7 0.56 A1609 AB 8901 13 25.8 +44 30 9.4 8.7 44 84.6 0.26 95.6 0.23 25 CVn 8974 13 37.5 +36 18 4.9 6.9 228 93.6 1.66 93.3 1.65 α Cen .. 14 39.6 –60 50 0.0 1.3 80 345.3 5.49 352.1 6.17 ζ Boo 9343 14 41.1 +13 44 4.4 4.5 125 280.1 0.25 280.0 2.44

φ309 .. 14 46.2 –21 11 7.3 7.3 13 217.2 0.12 301.7 0.07 ξ Boo 9413 14 51.4 +19 06 4.7 6.9 152 296.4 5.21 295.1 5.12 OΣ 288 9425 14 53.4 +15 42 6.8 7.5 313 155.6 0.95 155.0 0.93 H 4707 .. 14 54.2 –66 25 7.5 8.0 346 266.1 1.28 265.7 1.30 44 Boo 9494 15 03.8 +47 39 5.2 6.1 210 112.0 0.27 150.3 0.23

η CrB 9617 15 23.2 +30 17 5.6 5.9 41 279.9 0.36 305.4 0.37 γ Lup .. 15 35.1 –41 10 2.9 4.4 190 276.0 0.82 276.0 0.82 π2 UMi 9769 15 39.6 +79 59 7.3 8.1 172 20.6 0.60 20.9 0.60 ξ Sco AB 9909 16 04.4 –11 22 5.1 4.8 46 11.5 1.13 13.0 1.13 σ CrB AB 9979 16 14.7 +33 52 5.6 6.5 136 209.6 7.27 136.9 7.30

λ Oph 10087 16 30.9 +01 59 4.1 5.1 129 45.2 1.40 46.2 1.40 ζ Her 10157 16 41.3 +31 36 2.9 5.4 34 106.1 1.40 100.9 1.44 20 Dra 10279 16 56.4 +65 02 7.0 7.3 422 66.3 1.13 66.4 1.13 MlbO 4 AB .. 17 19.0 –34 59 6.3 7.3 42 347.2 0.78 330.7 1.07 BrsO 13 .. 17 19.1 –46 38 5.6 8.8 953 258.8 10.76 259.2 10.83

26 Dra 10660 17 35.0 +61 53 5.2 8.5 76 191.5 0.45 181.3 0.56 τ Oph 11005 18 03.1 –08 11 5.2 5.8 257 289.3 1.47 289.9 1.46 70 Oph 11046 18 05.5 +02 30 4.2 6.1 88 121.7 6.61 120.9 6.65 h 5014 .. 18 06.8 –43 25 5.6 5.6 450 357.7 1.75 357.4 1.75 OΣ 358 11483 18 35.9 +16 59 6.9 7.0 380 143.6 1.48 143.1 1.48

ε1 Lyr AB 11635 18 44.3 +39 40 5.1 6.1 1725 344.3 2.31 344.2 2.29 ε2 Lyr CD 11635 18 44.3 +39 40 5.2 5.3 724 74.0 2.40 73.7 2.40 γ CrA .. 19 06.4 –37 04 4.5 6.4 122 328.5 1.50 324.9 1.53 δ Cyg 12880 19 45.0 +45 08 2.8 6.2 918 215.1 2.77 214.9 2.78 λ Cyg 14296 20 47.4 +36 29 4.7 6.2 391 358.1 0.92 357.7 0.92

4 Aqr 14360 20 51.4 –05 38 6.4 7.4 201 32.5 0.74 33.4 0.73 ε Equ AB 14499 20 59.1 +04 18 5.9 6.3 104 275.4 0.07 239.5 0.02 τ Cyg 14787 21 14.8 +38 03 3.8 6.5 49 183.7 1.01 179.7 1.01 μ Cyg 15270 21 44.1 +28 45 4.7 6.1 789 326.4 1.46 327.6 1.44 53 Aqr 15934 22 26.6 –16 45 6.2 6.3 3500 81.7 1.33 85.7 1.36

Kr 60 15972 22 28.0 +57 42 9.9 11.4 45 217.2 1.89 206.7 2.04 ζ Aqr AB 15971 22 28.8 –00 01 4.3 4.4 540 155.1 2.29 154.1 2.31 π Cep 16538 23 07.9 +75 23 4.6 6.8 163 3.4 1.12 59.2 0.01 β 80 16665 23 18.9 +05 24 8.1 9.3 97 253.5 0.83 255.2 0.85 72 Peg 16836 23 34.0 +31 20 5.6 6.1 492 107.1 0.58 107.7 0.58

BAA Handbook 2020 Double Stars 109 BRIGHT STARS FOR EPOCH 2020.5 Name RA Dec. V Name RA Dec. V h m s ° ' " h m s ° ' " α And 0 09 27.1 +29 12 13 2.07 α UMa 11 04 58.5 +61 38 24 1.81 β Cas* 0 10 17.1 +59 15 46 2.28 β Leo 11 50 06.2 +14 27 27 2.14 α Cas 0 41 41.0 +56 38 58 2.24 α Cru† 12 27 45.2 –63 12 45 0.77 β Cet 0 44 37.0 –17 52 28 2.04 γ Cru* 12 32 18.9 –57 13 40 1.59 β And 1 10 53.2 +35 43 43 2.07 γ Cen† 12 42 39.4 –49 04 20 2.20 α Eri 1 38 28.5 –57 07 59 0.45 β Cru* 12 48 56.0 –59 48 02 1.25 γ And 2 05 10.0 +42 25 38 2.10 ε UMa* 12 54 55.5 +55 50 56 1.76 α Ari 2 08 20.0 +23 33 30 2.01 ζ UMa 13 24 44.9 +54 49 08 2.23 α UMi* 2 57 49.6 +89 21 00 1.97 α Vir* 13 26 16.5 –11 16 04 0.98 β Per* 3 09 30.6 +41 01 59 2.09 ε Cen 13 41 12.0 –53 34 11 2.29 α Per 3 25 47.8 +49 55 57 1.79 η UMa 13 48 20.8 +49 12 41 1.85 η Tau 3 48 42.4 +24 10 01 2.85 β Cen* 14 05 17.3 –60 28 15 0.61 α Tau 4 37 06.0 +16 32 56 0.87 θ Cen 14 07 53.8 –36 28 12 2.06 β Ori 5 15 31.4 –8 10 46 0.18 α Boo 14 16 35.8 +19 04 35 –0.05 α Aur* 5 18 12.4 +46 01 00 0.08 η Cen* 14 36 49.0 –42 14 48 2.33 γ Ori 5 26 13.9 +6 22 00 1.64 α Cen cg* 14 41 00.5 –60 55 12 –0.01 β Tau 5 27 35.4 +28 37 22 1.65 α Lup* 14 43 18.2 –47 28 30 2.30 δ Ori* 5 33 03.3 +0 17 08 2.25 ε Boo 14 45 52.9 +26 59 19 2.35 ε Ori 5 37 15.3 –1 11 25 1.69 β UMi 14 50 40.0 +74 04 18 2.07 ζ Ori 5 41 47.6 –1 56 00 1.74 α CrB* 15 35 33.4 +26 38 48 2.22 κ Ori 5 48 43.8 –9 39 50 2.07 δ Sco 16 01 33.0 –22 40 43 2.29 α Ori* 5 56 16.9 +7 24 33 0.45 α Sco* 16 30 40.1 –26 28 33 1.06 β Aur* 6 01 02.0 +44 56 50 1.90 α TrA 16 50 51.2 –69 03 44 1.91 β CMa* 6 23 36.2 –17 58 03 1.98 ε Sco 16 51 29.7 –34 19 43 2.29 α Car* 6 24 24.4 –52 42 27 –0.62 λ Sco* 17 35 00.1 –37 07 00 1.62 γ Gem 6 38 53.7 +16 22 48 1.93 α Oph 17 35 53.2 +12 32 48 2.08 α CMa 6 46 02.7 –16 44 46 –1.44 θ Sco 17 38 47.6 –43 00 31 1.86 ε CMa 6 59 25.9 –29 00 04 1.50 γ Dra 17 57 05.0 +51 29 14 2.24 δ CMa 7 09 13.5 –26 25 37 1.83 ε Sgr 18 25 31.9 –34 22 23 1.79 α Gem† 7 35 54.0 +31 50 28 1.58 α Lyr 18 37 38.0 +38 48 14 0.03 α CMi 7 40 22.5 +5 10 14 0.40 σ Sgr 18 56 32.1 –26 16 10 2.05 β Gem 7 46 34.1 +27 58 30 1.16 β Cyg† 19 31 32.9 +28 00 14 3.05 ζ Pup 8 04 18.3 –40 03 43 2.21 α Aql 19 51 47.0 +8 55 26 0.76 γ Vel* 8 10 09.9 –47 23 52 1.75 γ Cyg 20 22 57.9 +40 19 23 2.23 ε Car* 8 22 56.0 –59 34 33 1.86 α Pav 20 27 15.4 –56 40 03 1.94 δ Vel 8 45 16.2 –54 47 05 1.93 α Cyg 20 42 07.9 +45 21 16 1.25 λ Vel* 9 08 45.1 –43 30 58 2.23 α Cep 21 19 04.0 +62 40 22 2.45 β Car 9 13 25.0 –69 48 07 1.67 ε Peg* 21 45 11.6 +9 58 11 2.38 ι Car* 9 17 38.3 –59 21 42 2.21 α Gru 22 09 30.9 –46 51 39 1.73 α Hya 9 28 35.7 –8 44 54 1.99 β Gru* 22 43 53.0 –46 46 37 2.07 α Leo 10 09 27.7 +11 51 59 1.36 α PsA 22 58 46.7 –29 30 47 1.17 γ Leo† 10 21 06.0 +19 44 13 2.01 β Peg* 23 04 46.3 +28 11 40 2.44 β UMa 11 03 03.9 +56 16 19 2.34 α Peg 23 05 47.0 +15 18 57 2.49

* = Variable star † = Double star

Note: double star co–ordinates refer to the brighter component, but magnitude refers to the combined light. 110 Bright Stars BAA Handbook 2020 ACTIVE GALAXIES

Object RA Dec. Const. Type V* U.2000 (2000.0) Chart No. h m ° 3C 66A 2 22 +43.0 And BL Lac 14.0 – 16.3 62 NGC 1275 3 20 +41.5 Per Seyfert 13.2 – 13.7 63 3C 120 (BW Tau) 4 33 +05.4 Tau BL Lac 13.7 – 14.6 178 S5 0716+71 7 22 +71.3 Cam BL Lac 12.3 – 15.3 21 OJ+287 8 54 +20.1 Cnc BL Lac 12.4 – 16.0 142 Markarian 421 11 04 +38.2 UMa BL Lac 12.3 – 14.2 106 NGC 4151 12 10 +39.4 CVn Seyfert 11.0 – 12.4 74 W Comae 12 21 +28.2 Com BL Lac 11.5 – 16.0 148 3C 273 12 26 +02.3 Vir Quasar 12.3 – 13.3 238 3C 279 12 56 –05.8 Vir Quasar 11.5 – 17.0 239 BL Lacertae 22 02 +42.3 Lac BL Lac 12.5 – 15.5 87

*Approximate range

FINDER CHARTS FOR ACTIVE GALAXIES

Charts for all of the active galaxies listed above have been included in previous BAA Handbooks and are listed below.

Object BAA VSS Chart Handbook Year 3C 66A 309.01 2010 NGC1275 296.01 2008 BW Tau 320.01 2011 S5 0716+71 310.01 2009 OJ+287 208.02 2004 Markarian 421 243.01 2001 NGC4151 297.01 2007 W Com 148.03 2002 3C 273 244.01 2003 3C 279 151.02 2006 BL Lac 242.01 2005

Direct links to individual BAA VSS charts for the Active Galaxies can be found in a more detailed table of these galaxies, on the Computing Section website at:

http://britastro.org/computing/handbooks_active.html

BAA Handbook 2020 Active Galaxies 111 TIME

Universal Time (UT, Greenwich Mean Time beginning at midnight) is used generally throughout the Handbook.

Terrestrial Time (TT) is the uniform time system used in computing the ephemerides of the bodies of the Solar System. TT is currently ahead of UT by a small amount ΔT which must be determined by observations; thus TT = UT + ΔT The value of ΔT for July 2020 is estimated to be about 70.2 seconds.

Greenwich Mean Astronomical Time (GMAT), or Greenwich Mean Time beginning at noon, was in use before 1925 January 1, and many astronomical records prior to that date are referred to this system. To convert UT to GMAT subtract 12 hours, and to convert GMAT to UT add 12 hours.

Greenwich Sidereal Time (GST) is given in the table below at 0h UT. It may be obtained with sufficient accuracy for setting the circles of a telescope at any other time by adding 3.94 minutes for every complete day after a tabulated date, together with the correction, ΔT, for parts of a day from the table which follows: Time ΔT Time ΔT Time ΔT Time ΔT h m h m h m h m 0 00.0 m 5 46.9 m 11 52.2 m 17 57.4 m 0.0 1.0 2.0 3.0 0 18.2 6 23.5 12 28.7 18 33.9 0.1 1.1 2.1 3.1 0 54.7 7 00.0 13 05.3 19 10.5 0.2 1.2 2.2 3.2 1 31.3 7 36.5 13 41.7 19 47.0 0.3 1.3 2.3 3.3 2 07.8 8 13.0 14 18.3 20 23.5 0.4 1.4 2.4 3.4 2 44.3 8 49.6 14 54.8 21 00.0 0.5 1.5 2.5 3.5 3 20.8 9 26.1 15 31.3 21 36.6 0.6 1.6 2.6 3.6 3 57.4 10 02.6 16 07.8 22 13.1 0.7 1.7 2.7 3.7 4 33.9 10 39.1 16 44.4 22 49.6 0.8 1.8 2.8 3.8 5 10.4 11 15.6 17 20.9 23 26.1 0.9 1.9 2.9 3.9

For greater accuracy (±0.2S) use the equation : GST (at 0h UT) = ' 6.609078h + 0.06570982h d where d is the number of days from January 0.

The tabulated sidereal time is actually the mean sidereal time. The difference between mean and apparent sidereal time is never more than about 1.2 seconds. Local Sidereal Time (LST) and Local Hour Angle (LHA) are found from LST = GST + λ LHA = LST – RA Where λ is the longitude, expressed in time, measured positive eastwards from Greenwich.

The Julian Date, in which the day begins at noon, is used in accurate computing work and is given in the table on p.111.

The Sun’s Longitude is used as a measure of time in meteor work. It may be interpolated from the table on p.111.

112 Time BAA Handbook 2020 TIME Julian Sun's Long. Julian Sun's Long. 2019/20 Date GST 2000.0 2020 Date GST 2000.0 2458 h m ° 2459 h m °

Dec 29 846.5 6 28.66 276.68 Jul. 1 031.5 18 38.04 99.35 5.10 4.77 Jan. 3 851.5 6 48.37 281.78 6 036.5 18 57.75 104.12 5.09 4.76 8 856.5 7 08.09 286.87 11 041.5 19 17.46 108.88 5.10 4.77 13 861.5 7 27.80 291.97 16 046.5 19 37.18 113.65 5.09 4.77 18 866.5 7 47.51 297.06 21 051.5 19 56.89 118.42 5.09 4.78 23 871.5 8 07.22 302.15 26 056.5 20 16.60 123.20 5.09 4.78 28 876.5 8 26.94 307.24 Aug. 31 061.5 20 38.54 127.98 5.08 4.78 Feb. 2 881.5 8 46.65 312.32 5 066.5 20 56.03 132.76 5.07 4.79 7 886.5 9 06.36 317.39 10 071.5 21 15.74 137.55 5.06 4.80 12 891.5 9 26.08 322.45 15 076.5 21 35.46 142.35 5.05 4.81 17 896.5 9 45.79 327.50 20 081.5 21 55.17 147.16 5.05 4.82 22 901.5 10 05.50 332.55 25 086.5 22 14.88 151.98 5.03 4.83 27 906.5 10 25.21 337.58 30 091.5 22 34.59 156.81 5.02 4.84 Mar. 3 911.5 10 44.93 342.60 Sep. 4 096.5 22 54.31 161.65 5.01 4.84 8 916.5 11 04.64 347.61 9 101.5 23 14.02 166.49 4.99 4.87 13 921.5 11 24.35 352.60 14 106.5 23 33.73 171.36 4.98 4.88 18 926.5 11 44.07 357.58 19 111.5 23 53.45 176.24 4.97 4.89 23 931.5 12 03.78 2.55 24 116.5 0 13.16 181.13 4.95 4.90 28 936.5 12 23.49 7.50 29 121.5 0 32.87 186.03 4.94 4.91 Apr. 2 941.5 12 43.21 12.44 Oct. 4 126.5 0 52.58 190.94 4.93 4.93 7 946.5 13 02.92 17.37 9 131.5 1 12.30 195.87 4.90 4.95 12 951.5 13 22.63 22.27 14 136.5 1 32.01 200.82 4.90 4.96 17 956.5 13 42.34 27.17 19 141.5 1 51.72 205.78 4.88 4.98 22 961.5 14 02.06 32.05 24 146.5 2 11.44 210.76 4.88 4.98 27 966.5 14 21.77 36.93 29 151.5 2 31.15 215.74 4.85 5.00 May 2 971.5 14 41.48 41.78 Nov. 3 156.5 2 50.86 220.74 4.85 5.01 7 976.5 15 01.20 46.63 8 161.5 3 10.58 225.75 4.83 5.03 12 981.5 15 20.91 51.46 13 166.5 3 30.29 230.78 4.82 5.04 17 986.5 15 40.62 56.28 18 171.5 3 50.00 235.82 4.82 5.05 22 991.5 16 00.34 61.10 23 176.5 4 09.71 240.87 4.80 5.06 27 996.5 16 20.05 65.90 28 181.5 4 29.43 245.93 4.80 5.06 Jun. 1 001.5 16 39.76 70.70 Dec. 3 186.5 4 49.14 250.99 4.78 5.07 6 006.5 16 59.47 75.48 8 191.5 5 08.85 256.06 4.78 5.09 11 011.5 17 19.19 80.26 13 196.5 5 28.57 261.15 4.78 5.09 16 016.5 17 38.90 85.04 18 201.5 5 48.28 266.24 4.77 5.09 21 021.5 17 58.61 89.81 23 206.5 6 07.99 271.33 4.78 5.09 26 026.5 18 18.33 94.59 28 211.5 6 27.70 276.42 4.76

The precession in longitude from 2000.0 to 2020.0 is +0.28° and from 2000.0 to 1950.0 is –0.70°.

BAA Handbook 2020 Time 113 ASTRONOMICAL AND PHYSICAL CONSTANTS General: Gaussian gravitational constant 0.01720209895 Astronomical unit (au) 149,597,870,700 metres Speed of light in vacuo 299,792.458 km s–1 Dynamical form–factor J2 for the Earth 0.001082636 Product of gravitational constant and mass of the Earth 398,600.5 km3 s–2 Earth–Moon mass ratio 81.3006 Moon’s sidereal mean motion 2.661699489x10–6 radians s–1 = 0.5490149294" s–1 Obliquity of the ecliptic (2000) 23° 26' 21.448" Constant of nutation in obliquity (2000) 9.2052331" Solar parallax 8.794143" Light–time for unit distance 499.004784 s = 0.005775518 d Constant of aberration 20.49551" Mean distance Earth to Moon 384,400 km Constant of sine Moon’s parallax 3422.451" Lunar inequality 6.43987" Parallactic inequality 124.986" Length of the year: Tropical (equinox to equinox) 365.24219d Sidereal (fixed star to fixed star) 365.25636d Anomalistic (apse to apse) 365.25964d Eclipse (Moon’s node to Moon’s node) 346.62003d Gaussian (Kepler’s law for a = 1) 365.25690d Length of the month: Tropical (equinox to equinox) 27.32158d Sidereal (fixed star to fixed star) 27.32166d Anomalistic (apse to apse) 27.55455d Draconic (node to node) 27.21222d Synodic (New Moon to New Moon) 29.53059d Length of the day: Mean solar day 24h 03m 56.555s = 1.00273791d mean sidereal time Mean sidereal day 23h 56m 04.091s = 0.99726957d mean solar time Sidereal rotation period of the Earth 23h 56m 04.099s = 0.99726966d mean solar time Solar radiation: Solar constant 1.366 x 103 J m–2 s–1 Radiation emitted 3.84 x 1026 J s–1 Radiation emittance at surface 6.32 x 107 J m–2 s–1 Total internal radiant energy 2.8 x 1040 J Radiation emitted per unit mass 1.932 x 10–4 J s–1 kg–1

Visual absolute magnitude (Mv) +4.82 Colour indices (B–V, U–B) +0.65, +0.19 Spectral type G2V Effective temperature 5,800 K Conversion factors: Light–year (ly) 9.4607 x 1012 km = 63,240 au = 0.30660 pc Parsec (pc) 30.857 x 1012 km = 206,265 au = 3.2616 ly

114 Astronomical and Physical Constants BAA Handbook 2020 ASTRONOMICAL AND PHYSICAL CONSTANTS

The Galaxy: Pole of galactic plane (2000) 12h 51m 26.28s, δ +27° 07' 42.0" Point of zero longitude (2000) 17h 45m 37.22s, δ –28° 56' 10.2" Galactic Longitude of North Celestial Pole (2000) 122.93° Mass 1.1 x 1011 solar masses = 2.2 x 1041 kg Average density 0.1 solar mass pc–3 = 7 x 10–21 kg m–3 Diameter 25,000 pc Thickness 4,000 pc Distance of Sun from centre 8,200 pc Distance of Sun above galactic plane 24 ±6 pc Solar apex (2000) (from radio astronomy) RA 18h 03.8m , Dec. 30° 00' Solar motion (from bright stars) 19.7 km s–1 Period of revolution of Sun about centre 2.2 x 108 yr Figure of the Earth: Equatorial radius 6,378,136.6 m Polar radius 6,356,751.9 m Flattening 0.0033528197 * ρ sin φ' = S sin φ, ρ cos φ' = C cos φ where: S = 0.99497418 – 0.00167082 cos 2φ +10–8 (210 cos 4φ + 15.7 h) C = 1.00167997 – 0.00168208 cos 2φ +10–8 (212 cos 4φ + 15.7 h) ρ = 0.99832707 + 0.00167644 cos 2φ –10–8 (352 cos 4φ – 15.7 h) + 10–8 cos 6φ tan φ' = [0.9933054 + (0.11 x 10–8 h)] tan φ φ – φ' = 692.74" sin 2φ – 1.16" sin 4φ 1° of latitude = [111.1333 – 0.5598 cos 2 φ + 0.0012 cos 4φ] km 1° of longitude = [111.4133 cos φ – 0.0935 cos 3 φ + 0.0001 cos 5φ] km Acceleration due to gravity g = 9.780310 [1 + 0.00530239 sin2φ – 0.00000587 sin2 2φ – (31.55 x 10–8) h] m s–2 Length of seconds pendulum l = [0.9935769 – 0.0026272 cos 2φ + 0.0000029 cos 4φ – (3133 x 10–10) h] m

Constant of gravitation 6.67430 x 10–11 kg–1 m3 s–2 Centennial general precession p = 5028.796195" + 2.2108696" T† ______* φ = Geographic or geodetic latitude ρ = Geocentric distance in equatorial radii φ' = Geocentric latitude h = Height in metres † T = Time measured in Julian centuries from J2000.0

GREEK ALPHABET

α alpha β beta γ gamma δ delta ε epsilon ζ zeta η eta θ theta ι iota κ kappa λ lamda μ mu ν nu ξ xi ο omicron π pi ρ rho σ sigma τ tau υ upsilon φ phi χ chi ψ psi ω omega

BAA Handbook 2020 Astronomical and Physical Constants & Greek Alphabet 115 ACKNOWLEDGEMENTS The Handbook would not be possible without the work of its many data contributors :

Andrew Sinclair contributed the diagrams showing the visibility of planets and their appearances and also data and diagrams for Saturn's satellites. Barry Leggett supplied data for Jovian satellite eclipses and transits. Des Loughney provided heliocentric times of primary minima of variable stars. Fred Espenak (previously of the NASA/Goddard Space Flight Center) for his Eclipse charts. Bob Dryden contributed the data on Mira stars. Jay Andersen contributed the cloud coverage charts for solar eclipse. (p.17) John Mason provided the meteor data. John Toone provided data on active galaxies. Gary Poyner provided data for variable stars and for the variable star of the year. Nick James provided data on comets. Charts produced using Megastar 4 software. Ken Hall provided lunar libration data. Richard Miles provided data for asteroids, near–earth objects, trans–neptunian and dwarf planets, and diagrams for Pluto. Asteroid Favourable Observing Opportunities data were prepared by him, using data from the MPCORB database by Brian D. Warner; Alan W. Harris (MoreData! Inc.); and Petr Pravec (Astronomical Institute, Ondrejov, Czech Republic). Richard Kaye provided the System III Jupiter data, using a program written by himself. Robert Mackenzie provided the start dates for Carrington rotations. Susan Stewart of the United States Naval Observatory provided the bright stars positional data. Tim Haymes provided lunar occultation data and, with Edwin Goffin and Eberhard Riedel (International Occultation Timing Association), the tables and maps for asteroid occultations and grazing lunar occultations. Mike Kretlow for use of his asteroid and TNO database of current predictions. Steve Bell (Her Majesty's Nautical Office) provided various data. Steve Preston for his global updates on asteroidoccultations.com Tony Evans provided data for Mercury, Venus and Mars. William Thuillot (Institut de Mécanique Céleste et de Calcul des Ephémérides) supplied the diagrams of Jupiter’s satellites.

Contributors have checked their own and others’ contributions and their comments have greatly improved the Handbook. The Editor gratefully acknowledges contributors’ support in answering any queries, and the many proof readers for their assistance. Any data not mentioned above have been provided by the Computing Section. STEVE HARVEY Director

ERRATA Handbook 2019 p.4 Entry '6 18 18 Mercury 0.2° of Mars' should be 0.2°N . p.5 Entry '7 12 05 Mercury greatest elongation' should be deleted. p.30 June 23 rise and set times should read ––:–– /09:44 p.52 The UT value for 489 Comacina should be 00:15, not 01:15. p.109 lamba Cygni STT413 ADS 14296 should have a period 391years and rho value 0.92.

116 Acknowledgements & Errata BAA Handbook 2020 The British Astronomical Association The British Astronomical Association was founded in 1890 and now has about 3,000 members. Its leading features are:

Membership – Open to all persons interested in astronomy.

Objectives – (1) The organisation of observers, including those using small telescopes or binoculars, for mutual help. (2) The analysis and publication of observations. (3) The circulation of current astronomical information. (4) The encouragement of a popular interest in astronomy.

Methods – (1) The organisation of members in sections under experienced directors. (2) The publication of a Journal, Newsletters, a Handbook and Bulletins. (3) The holding of meetings and workshops. (4) The affiliation of schools and societies.

Annual Subscriptions – Current rates are available from the Office.

MEETINGS Meetings are held at approximately monthly intervals, excluding July and August. Many are in London on either Wednesdays (starting at 17.30) or Saturdays (starting at 14.30). Meetings are also held at venues around the country. A very popular weekend meeting is held annually near Winchester in the Spring, along with a Summer Meeting or Exhibition. Back–to–Basics meetings for beginners are held outside London each year, usually in March and October. Observers’ workshops are also held twice per year. Many observing sections hold meetings every few years, some annually. Full details of the current programme are available from the office and the website.

PUBLICATIONS The principal publications are the Journal and the Handbook. In addition, e–mailed bulletins and section newsletters are available to members. The Journal is published six times a year. It contains reports of meetings, reports of the sections, papers, reviews, letters, images and notes on current astronomical news. The complete set of Journals from 1890 is available on DVD. Occasional longer Memoirs containing detailed section reports. This Handbook, prepared by the Computing Section, is published annually. The e–bulletins give early information on new and predicted events such as planetary phenomena and the dis- covery of novae and comets.

REGISTERED OFFICE The Registered Office of the Association is at Burlington House, Piccadilly, London, W1J 0DU. Email: [email protected] Telephone 020 7734 4145. Hours are 09.00 to 17.00, Monday to Friday. The BAA on the Internet BAA Home Page http://britastro.org

This website contains information about the BAA and how to become a member; it gives details about the meetings, publications and merchandise for sale. There is a “members only” area, plus links to pages maintained by the Observing Sections. You can find tutorials, news items, data on new comets, asteroid occultations and other topical events, plus photo galleries and links to many other sources of astronomical information. Members can also particpate by creating their own page for sharing observations.

BAA Computing Section http://britastro.org/computing

This website complements the Handbook by providing extra material for which there is not enough room in the Handbook. including : charts for many minor planets, calculational forms, graphical applications such as what is observable at any time and positions of satellites of major planets. Constant data that do not need to be printed every year, together with links to other useful websites.

BAA Journal http://britastro.org/journal

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