JANUARY 2021 OBSERVING Celestial Calendar by Bob King Sky Highlights for 2021

Courtesy of Sky & Telescope

Sky Highlights for 2021 A full year of observing enjoyment awaits.

F or our January Celestial Calendar installment, we’ve decided to pres- The limb of the eclipsed ent a “sneak-peek” selection of some of the most interesting celestial Moon pokes out from highlights for 2021. (Each event will be described in greater detail in upcoming issues.) the umbra in this photo The coming year has its share of excitement, with several fi ne eclipses, captured during the the return of a few modestly bright periodic comets, and the usual April 15, 2014, total assortment of meteor showers and eye-catching conjunctions. lunar eclipse. This view January 3: The Quadrantid meteor shower peaks around 6:30 a.m. PST is similar to how the (14:30 UT). The timing of the peak means the display favors skywatchers Moon will appear at on the West Coast and in Alaska. Unfortunately, light from the waning gibbous Moon in Leo will blot out many of the fainter meteors. maximum eclipse during March 4: Vesta, the brightest and second-most massive asteroid, reaches November’s partial lunar opposition 1¼° northeast of 3.3-magnitude Theta Leonis, in the tail of eclipse. Leo. At magnitude 6.0, Vesta is bright enough to be glimpsed by keen- eyed observers without optical aid from a dark sky. Binoculars will make

the asteroid an easy catch. KING BOB

Page 1 BOB KING March 5 March cury Moon March 10 +0.1. magnitude at Mercury –2.0, and at magnitude shine will Jupiter date, this On at dawn. 21just April 2 April 14°. about span will group The twilight. May 12 of357,377tance (222,063 km miles). atadis- later, 12 hours than less little perigee (3:31EDT 27th) reaches April UT, and at11:31 full is Moon The p.m. tonight. a“supermoon”), occurs called ularly 26 April twilight. evening during sky western the lowin very 1° apart and 25 April star.) the Iooccults America, ofSouth regions northern and America Central in (From locations America. ofNorth middle the in observers favors and sky southeastern the lowin Jupiter with occurs 5:20 event CDT. a.m. The nitude star 44 Capricorni 0.5 just passes visible from western North America, America, North western from visible May 26 atdusk. west-northwest cent hours of January3rd. Given thetiming ofthedisplay’speak,best timetolookwillbeinthepredawn from awaning gibbous Moon,whichrisesin theearlyeveningonJanuary 2nd. SJanuary 2021'sQuadrantidmeteor showerwillbehamperedsomewhatbylight Page 2 Polaris MINOR Venus Moon , Jupiter URSA joins the planetary trio of trio planetary the joins (when it’s closest to Earth) a Earth) (when to it’s closest apart, low in the east-southeast east-southeast the lowin ′ apart, : Jupiter’s innermost moon, moon, : Jupiter’s innermost : Atotal lunar eclipse : Venus : : Mercury A perigean full Moon full : Aperigean Mercury : A thin, waning crescent crescent waning : Athin, are only 1° apart, low in the the lowin 1° only are apart, (–3.9) are a little more than (–3.9) than more alittle are DRACO south of the 5.9-mag- ofthe ″ south and Saturn, and and a very thin cres- thin avery and Dipper Little (magnitude –1.6) (magnitude and Jupiter and around in morning is Looking Northeast ECULES HERC are are Mer- (pop- Io , Quadrantid radiant nearly full Moon full nearly the watch can America ofNorth half 25June conjunction. this view to wide-fi or asmall, oculars bin- Use atdusk. sky northwestern the lowin Cancer, in (M44) Cluster hive ofthe middle the in smack-dab see can America 23 June 51 at10:42utes UT. seconds) occurs 3min- (lasting eclipse Greatest Moon. the by covered Sun ofthe 80% roughly with sunrise adramatic see will U.S. northeastern the in risers Early sunrise. at occurs eclipse maximum rior, where Supe- ofLake shore north the along end southern Pole) atits North except the (including locations remote mostly crosses ofannularity path The Russia. and Greenland, Canada, in visible is 10June 357,310perigee, Earth. from km reaching after 9hours than more little (at 11:15 full is moon.” Moon The a UT) “super- another presents also night (11:11 11:26 to this ithappens, As UT). 4:11 from 4:26 to lasting a.m. PDT a.m. brief, and bright relatively be will ity total- umbra, Earth’s the inside barely is limb Moon’s the northern Because event. ofthe part atleast see able to be will locations other many though nitude star Nunki MAJOR URSA Mizar Quadrantid MeteorShower : Skywatchers in the western western the in : Skywatchers : Observers across North North across : Observers : An annular solar eclipse : An Mars occult the 2nd-mag- the occult (Sigma Sagittarii), in in (Sigma Sagittarii), (magnitude 1.8) (magnitude BOÖTES eld telescope telescope eld 1 am,Jan3 Arcturus Bee- 10° my telescope’s reach. me totrackeveryfuture cometwithin watching thecometevolveinspired of Pollux,inGemini.Back1982, for viewing,positioned3°southwest helion (November2nd)it’s wellplaced grew apretty tail.Onthenightofperi- comet reached 9thmagnitudeand lar totheoneithadin1982,when system. Thisyear’s apparitionissimi- simenko returnstotheinnersolar Comet 67P/Churyumov-Gera- Sagittarius. travels from Ophiuchusinto southern in lateAugustandSeptemberasit brighten tomagnitude9atitspeak favorable return in2021andcould Comet 6P/d’Arrest hasamoderately early asApril. Ophiuchusas the cometinnorthern decades. You canbeginsearching for to beitsbestapparitioninseveral June. Comet-watchersexpectthis Piscis Austrinusduringmid-tolate sky asitshuttlesfrom Aquariusto reach magnitude10inthe morning a favorablereturn in2021andmay Comet 7P/Pons-Winneckemakes 2021 Returning Comets highlighted above. see —includingthe trioofperiodiccomets mon faintercometsrequire telescopesto rather thantherule.Themuchmore com- NEOWISE (C/2020F3)are theexception S Comets asspectacularlastsummer’s from the Americas, northern Europe, east Asia, Australia, and the Pacifi c. A full 97.4% of the Moon will dip into Earth’s umbral shadow. The remaining 2.6% of the southern limb will glow brightly, giving the Moon the appear- ance of Mars with a polar cap. First umbral contact is at 2:19 a.m. EST (7:19 UT); greatest eclipse is at 4:03 a.m.; and the Moon exits the umbra at 5:47 a.m. November 27: Ceres is at opposition and shines at magnitude 7.0 in Taurus. The asteroid spends November crossing the Hyades and on the night of Novem- ber 4-5 passes just a few arcminutes south of Aldebaran. December 5: Jupiter, Saturn, Venus, Shortly after Jupiter occults and the Moon form a spectacular 50°- 44 Capricorni on April 2nd, the long line in the western sky in twilight. star passes just 0.5″ north of the Jovian moon Io, as seen Over the following three evenings, the in this simulation. Moon will visit each planet in turn. Towards the end of December, Mercury joins the gathering. the early morning hours. the third full Moon in a season that December 14: The Geminid meteor July 11: The thin, waning crescent contains four. This is the original (and shower peaks around 2 a.m. EST Moon shines 5° right of Venus and largely forgotten) defi nition of the Blue (7 UT), which is nearly ideal for North Mars, which are separated by 1° low in Moon as outlined in the Maine Farmers’ American viewers. Unfortunately, the the western sky at dusk. On the 12th, Almanac. waxing gibbous Moon (80% illumi- Venus and Mars are a scant ½° apart September 14: Neptune is at opposi- nated) will spoil the show until it sets and shine at magnitudes of –3.9 and tion. at around 3 a.m. local time. For a few 1.8, respectively. November 4: Uranus is at opposition. hours before morning twilight, there August 2: Saturn is at opposition. November 19: A near-total lunar should be some excellent, moonfree August 12: The Perseid meteor eclipse occurs this morning, visible meteor watching. shower peaks in the predawn hours. The waxing crescent Moon won’t spoil the view because it sets around 10 p.m. local daylight time on the 11th. There might be a few extra meteors visible, courtesy of Comet Chacornac (C/1852 K1). On August 12th around 4:22 UT, the Earth will pass very close (15,000 km) to the comet’s dust tail. The radiant for the resulting meteors lies in south- eastern Cetus near the star Pi Ceti. August 18: The variable star Mira (Omicron Ceti) will be at or near its maximum brightness of magnitude 3. August 19: The waxing gibbous Moon occults Nunki (Sigma Sagittarii) for observers in the southernmost U.S., Central America, and northern South America. August 19: Jupiter is at opposition. August 22: This morning features a Seasonal Blue Moon, that is,

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