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Contents 2 Jan Mars shines brilliantly and looms large through a telescope this year as it puts on its best display in more than 10 years. NASA/JPL/USGS By Martin Ratcliffe Skyand Richard Talcott Guide 2016 contents 2 Jan. 2016 A stellar year for Aldebaran 3 Feb. 2016 Jupiter blazes across Leo 4 March 2016 Eclipse over Indonesia 5 April 2016 The Red Planet returns to glory 6 May 2016 Mercury transits the Sun 7 June 2016 Saturn’s summer splendor 8 July 2016 Tracking a recently exposed planet 9 Aug. 2016 The Perseids in prime time 10 Sept. 2016 Ice giants come in from the cold 11 Oct. 2016 Brilliant Venus rules the evening sky 12 Nov. 2016 The Sun’s dynamic face 13 Dec. 2016 A fleeting glimpse of Mercury 14 2017 Preview Looking ahead to next year . Martin Ratcliffe provides professional planetarium development for Sky-Skan, Inc. 15 Spacecraft A year of exploration Richard Talcott is a senior editor of Astronomy. 618329 A supplement to Astronomy magazine 2016 Jan S M T W T F S A stellar year for 1 3 4 5 6 7 8 10 11 12 13 14 15 Aldebaran 17 18 19 20 21 22 24 25 26 27 28 29 30 uring its monthly out. The star’s orbit around decline may be pro- Earth, the Moon longed if you live passes in front where the occul- 3 The Moon passes of thousands of tation occurs near 1.5° north of Mars, stars. Most of these distant suns the Moon’s curved 2 P.M. EST D are faint, however, and the so- northern or south- 4 Quadrantid meteor shower peaks called occultations that result ern limb. pass with little notice. Just four A few people 5 Pluto is in conjunc- tion with the Sun, 1st-magnitude stars — Aldeba- will get to witness a 10 P.M. EST ran, Antares, Regulus, and drama-filled grazing 6 Venus passes 6° Spica — lie close enough to the occultation. If you north of Antares, Moon’s path to get in on the view from a line that noon EST action. Aldebaran is 2016’s runs across north- The Moon passes clear winner, with the Moon ern Mexico and the 3° north of Venus, occulting it a dozen times. U.S. Gulf Coast (see 7 P.M. EST Ruddy Aldebaran sat to the upper right of a The best event for North the map below), crescent Moon August 9, 2015. A gibbous Moon The Moon passes American observers occurs the Aldebaran will skim occults the same star January 19. Tunç Tezel 3° north of Saturn, midnight EST evening of January 19. Resi- the Moon’s southern dents across Canada, most of limb, ducking behind though not all of these events 8 Venus passes 0.09° north of Saturn, the United States, and north- mountain ranges and reappear- are created equal. Some of the 11 P.M. EST western Mexico will see an ing in lunar valleys. This graze occultations occur when the 13 The Moon passes occultation. Set up early and track is only a few miles wide, Moon and star lie below the 2° north of Nep- center Aldebaran in your tele- but serious observers often horizon, and others when the tune, 10 A.M. EST scope’s eyepiece. Gradually, the travel large distances to be in Sun shares the sky and reduces 16 The Moon passes dark limb of the waxing gib- the path. Accurately timing the drama. 1.5° south of Ura- bous Moon will approach the when the star disappears and North American observers nus, 1 A.M. EST star. Although most stars dis- reappears gives astronomers have seven opportunities to 19 The Moon passes appear from view instanta- precise information about the see Aldebaran pass behind the 0.5° north of Aldeb- aran, 10 P.M. EST neously, Aldebaran is a red Moon’s limb profile. Moon during 2016. Events giant and likely will take a The Moon occults Aldeba- occur January 19, February 27 The Moon passes 1.4° south of Jupi- tenth of a second or so to fade ran once each orbit this year, 15/16 (western U.S. only), ter, 8 P.M. EST April 10 (daylight), July 29, CANADA August 25 (daylight), October Moon Phases 18/19, and December 12/13. Because the Moon’s orbit First Quarter lies close to the path of the Full Moon UNITED STATES solar system’s planets, Luna also occasionally occults one Last Quarter n of Earth’s neighbors. The best Aldebara New Moon cults n oc planetary occultation this year oo ble e M on visi The Moon’s comes September 2 when a Th ltati u southern limb Jaeger and Kellie : Roen Kelly occ No grazes Aldebaran 1.5-day-old Moon hides Jupi- Events that can be viewed M ter during daylight. Along with the naked eye E Astronomy X a track from Oregon to the Events that can be viewed I C 0 250 miles O Texas coast, the planet grazes with binoculars 0 500 km the northern lunar limb; peo- Events that can be viewed illustrations: All ple south of this line can view with a telescope People north of a line that runs across northern Mexico and southern Texas to the Georgia coast CIR-PB-618329_20will see the Moon occult Aldebaran on January 19. a complete occultation. 2 Sky Guide 2016 2016 Feb Jupiter blazes S M T W T F S 1 2 3 4 5 6 7 9 10 11 12 13 across Leo 14 16 17 18 19 20 21 23 24 25 26 27 28 29 upiter puts on an the star, impressive show and Jupiter throughout this appears as winter and spring. if it has Although it doesn’t gained a 1 The Moon passes 3° north of Mars, reach opposition and peak moon. J 4 A.M. EST visibility until March 8, few Jupiter 3 The Moon passes observers will notice any reaches oppo- 3° north of Saturn, difference in its appearance sition March 8, 2 P.M. EST during the longer nights of when it shines 6 The Moon passes January and February. brightest (magnitude 4° north of Venus, As 2016 opens, Jupiter –2.5) and remains visible all 3 A.M. EST Jupiter will look striking through dominates the late evening night. It is unmistakable in the amateur telescopes in the first The Moon passes sky. It rises before 11 p.m. local east as soon as night starts to half of 2016. The planet’s banded 4° north of Mer- time January 1 when it stands fall. The world also appears atmosphere and Great Red Spot cury, noon EST stand out in this image, captured Mercury is at in eastern Leo next to that largest at opposition, span- in December 2000 by the Cassini greatest western spacecraft. NASA/JPL/University of Arizona constellation’s border with ning 44" across its equator, elongation (26°), Virgo. The planet starts mov- though it stays above 43" from 8 P.M. EST ing westward relative to the early February to early April. near the planet, it means one 9 The Moon passes background stars just a week Any telescope delivers stun- or more of the moons is hiding 2° north of Nep- later, however, which carries it ning views of the giant planet. behind Jupiter’s disk or passing tune, 7 P.M. EST into the sparsely lit region of The smallest instruments in front of it. 12 The Moon passes southeastern Leo. Shining reveal two dark equatorial Larger scopes reveal finer 1.7° south of Ura- brighter than magnitude –2, belts straddling a brighter zone detail in the jovian atmosphere. nus, 9 A.M. EST Jupiter is the lone standout. that coincides with the planet’s A series of alternating bright 16 The Moon passes The giant world’s path has equator. Also look for Jupiter’s zones and darker belts comes 0.3° north of Aldeb- aran, 3 A.M. EST it heading straight for 4th- four biggest moons, which into view as do turbulent fea- σ 23 The Moon passes magnitude Sigma ( ) Leonis. change positions from night to tures in the swirl of clouds near 1.7° south of Jupi- On the night of March 2/3, the night and often by the hour. If the borders of these bands. ter, 11 P.M. EST planet passes just 14' south of you don’t see four bright dots Jupiter remains a fasci- 28 Neptune is in con- nating target throughout the junction with the N spring. On April 7/8, it slides Sun, 11 A.M. EST 7' north of 5th-magnitude Chi 29 The Moon passes (χ) Leonis. And it remains on 4° north of Mars, 1 P.M. EST LEO May 10 view past midnight local day- April 10 light time as late as early July. χ Although it dips lower as March 10 summer progresses, keep an E σ eye on Jupiter. On August 27, it has a fine conjunction with Feb 10 Jupiter reaches opposition March 8 Venus. The sky’s two brightest Jan 10 points of light then lie 5' apart and stand 5° above the western τ horizon 30 minutes after sun- 1° set. Jupiter passes behind the Sun in late September and a few weeks later returns to view The solar system’s biggest planet shines brilliantly nearly all night this winter and spring. It spendsCIR-PB-618329_21 this peak period in southeastern Leo, not far before dawn, where it remains from the border with Virgo.
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