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The British Astronomical Association Handbook 2018 THE HANDBOOK OF THE BRITISH ASTRONOMICAL ASSOCIATION 2018 2017 October ISSN 0068–130–X CONTENTS PREFACE . 2 HIGHLIGHTS FOR 2018 . 3 SKY DIARY . .. 4-5 CALENDAR 2018 . 6 SUN . 7-9 ECLIPSES . 10-15 APPEARANCE OF PLANETS . 16 VISIBILITY OF PLANETS . 17 RISING AND SETTING OF THE PLANETS IN LATITUDES 52°N AND 35°S . 18-19 PLANETS – Explanatin of Tables . 20 ELEMENTS OF PLANETARY ORBITS . 21 MERCURY . 22-23 VENUS . 24 EARTH . 25 MOON . 25 LUNAR LIBRATION . 26 MOONRISE AND MOONSET . 27-31 SUN’S SELENOGRAPHIC COLONGITUDE . 32 LUNAR OCCULTATIONS . 33-39 GRAZING LUNAR OCCULTATIONS . 40-41 MARS . 42-43 ASTEROIDS . 44 ASTEROID EPHEMERIDES . 45-49 ASTEROID OCCULTATIONS (incl. TNO Hightlight:1998 WV31) . 50-53 ASTEROIDS: FAVOURABLE OBSERVING OPPORTUNITIES . 54-56 NEO CLOSE APPROACHES TO EARTH . 57 JUPITER . .. 58-62 SATELLITES OF JUPITER . .. 62-66 JUPITER ECLIPSES, OCCULTATIONS AND TRANSITS . 67-76 SATURN . 77-80 SATELLITES OF SATURN . 81-84 URANUS . 85 NEPTUNE . 86 TRANS–NEPTUNIAN & SCATTERED-DISK OBJECTS . 87 DWARF PLANETS . 88-91 COMETS . 92-96 METEOR DIARY . 97-99 VARIABLE STARS (RZ Cassiopeiae; Algol; RS Canum Venaticorum) . 100-101 MIRA STARS . 102 VARIABLE STAR OF THE YEAR (VV Cephei) . .. .. 103-105 EPHEMERIDES OF VISUAL BINARY STARS . 106-107 BRIGHT STARS . 108 ACTIVE GALAXIES . 109 TIME . 110-111 ASTRONOMICAL AND PHYSICAL CONSTANTS . 112-113 INTERNET RESOURCES . 114-115 GREEK ALPHABET . 115 ACKNOWLEDGEMENTS / ERRATA . 116 Front Cover: Mars - Apparent Diam. 18.4" taken from Barbados on 2016 June 05 by Damian Peach using a 356mm aper- ture Schmidt-Cassegrain telescope (North up) British Astronomical Association HANDBOOK FOR 2018 NINETY–SEVENTH YEAR OF PUBLICATION BURLINGTON HOUSE, PICCADILLY, LONDON, W1J 0DU Telephone 020 7734 4145 PREFACE Welcome to the 97th Handbook of the British Astronomical Association. The Handbook tries to highlight 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. Don't forget the special BAA Summer Meeting & Joint BAAVSS-AAVSO Meeting to be held at Warwick University : Saturday-Sunday July 7-8 (Organisers: Hazel Collett & Roger Pickard). (https://britastro.org/node/10727) You may also like to consider getting involved with the annual events organised as part of World Space Week (4-10 Oct.). 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. However, the Computing Section does try to publish all additional data on the section website (http://britastro.org/computing). 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 2018 ! Steve Harvey Director, Computing Section Email: [email protected] August 2017 2 Preface BAA Handbook 2018 HIGHLIGHTS FOR 2018 The following events during 2018 are worthy of note: Sun and Moon: There will be five eclipses (three of the Sun and two of the Moon). All three solar eclipses are partial and in polar regions so will be difficult to observe, The two lunar eclipse are both full. The eclipse of July 27 will be the most central umbral shadow since 2011. It will be visible (having already started) from moonrise in the UK. Planets, Dwarf Planets and Asteroids: Mercury is best seen in northern latitudes in the mornings in early January and mid to late August (for southern latitudes it is best seen in early to mid-January and mid-April to mid-May. In the evenings it is best seen around March and mid-June to early July.(July and late October to mid-November for southern latitudes). Venus is an evening object throughout the middle months of the year, reaching inferior conjunction on 26 Oct.., and then a morning object at the end of the year. A favourable Conjunction occurs with Mars and Jupiter (7 Jan.). Mars rises from the early morning hours at the beginning of the year and is visible throughout the year. Mars reaches perihelic opposition Jul. 27 (05:14) , with a diameter of 24.3" and magnitude -2.8 (From Greenwich transit is at 00:14 13°S) Meteors: Among the meteor showers, the most favourable are: the Lyrids (April), Perseids (August) and Draconids(October). Also favourable are: Capricornids, ι-Aquarids, Taurids, Leonids and Geminids. Comets: The comets 21P/Giacobini-Zinner and 46P/Wirtanen, which may reach naked eye brightness. 46P/Wirtanen is a special target for Pro-am observations in 2018. Also worth note (due to its tendency to outburst) is 29P/ Schwassmann-Wachmann. Refer to the BAA Comet Section for latest info : http://britastro.org/comet Space Probes and Artificial Satellites: NASA will launch its first mission to the sun during the summer of 2018 - the Parker Solar Probe. The Juno probe will deorbit into Jupiter during February. ESA's mission to Mercury, BepiColombo is sched- uled for launch in October. Predictions for the International Space Station and other bright satellites can be found for any geographic location at: http://www.heavens-above.com Highlights by date: Jan. 7 Mars 0.2° South of Jupiter 31 Total lunar eclipse visible from north-west America, the Pacific, Asia and Australia Feb. 15 Partial solar eclipse visible over Antarctica and finishing in South America. Mar. 20 The vernal equinox occurs in the northern hemisphere at 16:16 UT Apr. 22 Lyrid meteor shower May 9 Jupiter at opposition Jun. 28 Saturn at opposition.
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