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Contents 2 Jan By Martin Ratcliffe and Richard Talcott Sky Guide 2018 Mars shines brilliantly and looms large through telescopes this year as it puts on its finest show since 2003. NASA/JPL-CALTECH contents 2 Jan. 2018 Eclipse of the Blue Moon 3 Feb. 2018 Target galaxies these cool winter nights 4 March 2018 Catch Mercury at dusk 5 April 2018 The Lyre plays a sweet meteor song 6 May 2018 Jupiter rules spring nights 7 June 2018 Saturn’s rings on gorgeous display 8 July 2018 Red Planet renaissance 9 Aug. 2018 Prime time for the Perseids 10 Sept. 2018 Venus blazes in the evening twilight 11 Oct. 2018 An ice giant butts into the Ram Martin Ratcliffe provides professional 12 Nov. 2018 Juno at its best in 35 years planetarium development for Sky-Skan, Inc. Richard Talcott is a senior editor of Astronomy. 13 Dec. 2018 Making a swing past Earth 14 2019 Preview Looking ahead to next year ... A supplement to Astronomy magazine 618364 2018 Jan. S M T W T F S Eclipse of the 2 3 4 5 6 7 9 10 11 12 13 14 15 17 18 19 20 Blue Moon 21 22 23 25 26 27 28 29 30 anuary features two third of the country experience Full Moons, both of only the initial partial phases. which command our The Moon dips into Earth’s attention. The first dark umbral shadow at 1 Mercury is at great- comes New Year’s 6:48 a.m. EST (3:48 a.m. PST), est western elonga- night and arrives less than five but the Moon sets before total- tion (23°), 3 P.M. EST J hours after our satellite’s clos- ity begins at 7:52 a.m. EST 3 Quadrantid meteor shower peaks est approach to Earth during (4:52 a.m. PST). 2018. Its 33.5' apparent diam- Viewers in the central U.S. 5 The Moon passes 0.9° north of eter makes it the biggest Full see at least some of the total Regulus, 3 A.M. EST Moon of the year — a “Super phase. The Moon passes closest Moon” in popular parlance. to the center of our planet’s A total lunar eclipse always looks 6 Mars passes 0.2° dramatic. Here, Greece’s Temple of south of Jupiter, The Full Moon before dawn shadow at 7:30 a.m. CST Poseidon stands before a February 11 P.M. EST January 31 is a touch smaller, (5:30 a.m. PST) and starts to 2008 eclipsed Moon. ANTHONY AYIOMAMITIS 9 Venus is in superior 33.2' across, and ranks as the exit the umbra at 8:08 a.m. CST conjunction, second largest of 2018. As the (6:08 a.m. PST). During the which wraps up at 7:11 a.m. 2 A.M. EST month’s second Full Moon, it 76 minutes of totality, the Moon PST. Observers in Alaska and Pluto is in conjunc- also will be touted as a “Blue should take on an orange glow, Hawaii can watch the final tion with the Sun, 5 A.M. EST Moon.” But to observers, the looking a bit like a Chinese lan- penumbral phases play out as January 31 Full Moon places tern dangling among the back- the Moon departs Earth’s 11 The Moon passes 4° north of Jupiter, first because it dives deeply ground stars of Cancer, with lighter outer shadow. 1 A.M. EST into Earth’s shadow, bringing Leo standing above. If the Moon’s position dur- The Moon passes the first total lunar eclipse Observers in the western ing totality seems familiar to 5° north of Mars, since September 2015. third of the U.S. get to see all you, it should. When the New 5 A.M. EST People across North of totality, and progressively Moon passed between the Sun 13 Mercury passes 0.6° America, the Pacific Ocean, more of the concluding partial and Earth last August 21, it south of Saturn, Australia, and Asia can see at phases the farther west they created a total solar eclipse in 2 A.M. EST least part of this eclipse. For live. People with clear skies in Leo. In the nearly half-year 14 The Moon passes those in the United States, bet- northern California, Oregon, since, the Sun has moved 3° north of Saturn, 9 P.M. EST ter views come the farther west and Washington can witness almost halfway around the sky, you live. Those in the eastern the entire umbral eclipse, so the Full Moon (which lies 15 The Moon passes 3° north of opposite the Sun) appears in Mercury, 2 A.M. EST N the same general area as last August’s New Moon. 20 The Moon passes Penumbra 1.6° south of The January 31 eclipse is Neptune, 3 P.M. EST the first of five during 2018, Partial 23 The Moon passes Umbra eclipse begins though it is by far the best for 5° south of Uranus, A.M. PST Partial Greatest eclipse 3:48 North Americans. A second 8 P.M. EST 5:30 A.M. PST E eclipse ends total lunar eclipse occurs 27 The Moon passes 7:11 A.M. PST July 27, but it completely 0.7° north of Aldebaran, misses the continent. The year 6 A.M. EST Penumbral also features three solar eclipse begins eclipses — on February 15, 31 Dwarf planet Ceres 2:51 A.M. PST is at opposition, Totality ends Totality begins July 13, and August 11 — but 8 A.M. EST Penumbral 6:08 A.M. PST 4:52 A.M. PST all are partials. The first two eclipse ends Total lunar eclipse, favor observers deep in the 8:08 A.M. PST 8 A.M. EST Southern Hemisphere, while The first total lunar eclipse since September 2015 graces the predawn skies the last occurs in northern above North America onASY-PB-618364_20 January 31. ALL ILLUSTRATIONS: ASTRONOMY: ROEN KELLY Europe and northern Asia. 2 Sky Guide 2018 2018 Feb. Target galaxies these S M T W T F S 1 2 3 4 5 6 8 9 10 cool winter nights 11 12 13 14 16 17 18 19 20 21 22 24 25 26 27 28 ate winter and early spring are superb times for galaxy hunters. By late eve- ning, Earth’s night- 1 The Moon passes 1.0° north of side has turned away from the L Regulus, 2 P.M. EST myriad stars and obscuring 7 The Moon passes clouds of gas and dust in the 4° north of Jupiter, Milky Way’s plane. In its place, 3 P.M. EST countless galaxies from the 8 The Moon passes depths of intergalactic space 4° north of Mars, swing into view. midnight EST To spot these “faint fuzzies,” 10 Mars passes 5° you’ll need a dark sky and a north of Antares, telescope. Choose a clear night 10 A.M. EST within a week of the New 11 The Moon passes 2° north of Saturn, Moon and plan an escape 10 A.M. EST from light-polluted skies to The beautiful spiral galaxies M81 (right) and M82 in Ursa Major make a fine Asteroid Juno is in starting point for an evening of galaxy hunting. JASE JENNINGS 14 the darkness of the country. conjunction with Your reward will be a treasure the Sun, 6 A.M. EST trove of spirals, ellipticals, and wonders lurking in Canes southwest lies a 9th-magnitude 15 Partial solar eclipse, clusters of galaxies. Venatici and Coma Berenices, elliptical, M85, which marks 4 P.M. EST The first good opportunity followed soon after by the the northern edge of the giant 17 Mercury is in supe- this year comes around the mother lode in Virgo. Let’s Virgo Cluster. rior conjunction, New Moon on February 15. start with the four 8th- and From M85 south into 7 A.M. EST The Last Quarter Moon exits 9th-magnitude galaxies in Virgo lie some two dozen gal- 20 The Moon passes Virgo and enters Libra on Canes Venatici. The standout axies that glow at 11th magni- 5° south of Uranus, 3 A.M. EST February 7, marking the start here is the Whirlpool Galaxy tude or brighter. All told, the of the galaxy-viewing season. (M51), a dazzling spiral that is cluster contains more than 23 The Moon passes 0.7° north Dark skies stretch through the a favorite of astroimagers. Aim 1,500 galaxies. The largest is of Aldebaran, 21st, when the waxing cres- your telescope 12° due west M87, a giant elliptical with a 1 P.M. EST cent Moon sets shortly before and you’ll land on another nice central black hole weighing midnight local time. spiral, M106. The Hunting several billion Suns. Several The tip of the galactic ice- Dogs boast two more gems other cluster members dwarf berg comes into view as Ursa — M63 and M94 — farther the Milky Way. Moon phases Major climbs in the northeast. south. M63 has broad spiral The Virgo Cluster spans First Quarter A great pair of galaxies, M81 arms in contrast to M94’s tight 15°. Ponder that as you gaze Full Moon and M82, reaches the same spiral. Small telescopes show toward Virgo and Coma altitude as Polaris around the core of each galaxy as a Berenices — a cluster of galax- Last Quarter 7 p.m. local time, just as twi- faint smudge similar to a com- ies some 55 million light-years New Moon light ends. About three hours et’s head, while larger scopes distant so big that it spans later, Leo achieves the same reveal the fainter extremities.
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