Astronomy Club of Asheville January 2016 Sky Events

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1 January 2016 Sky Events The Planets this Month - page 2 Planet Highlights - page 7 All 5 Naked-Eye Planets in the Dawn Sky - page 10 Moon Phases - page 11 Earth Reaches Perihelion on Jan. 4 - page 12 Quadrantid Meteor Shower Peaks - page 13 Comet Catalina in the Early Morning Sky - page 14 Lunar Occultation of the Star Aldebaran - page 18

2 January 2016 Sky Events the Planets The only naked-eye planet visible in the early evening sky this month is Mercury, and its twilight appearance will last for only the first week of the January. Find Mercury very low in the SW at dusk; use binoculars to assist you in spotting it. Mercury reaches inferior conjunction (passing between the Earth and the Sun) on January 14 th. At its next inferior conjunction on May 9 th, Mercury will pass directly across the Sun s disk for its first transit in 10 years. With clear skies, this 7½ hour event will be visible in its entirety from Asheville.

3 January 2016 Sky Events the Planets Uranus and Neptune continue to be visible in the early evening sky. Find them shortly after dark - Uranus in the constellation Pisces and Neptune in the constellation Aquarius. You will need to observe these two planets early, before they set this month. Neptune is best viewed just after dark during the first two weeks of the month, and Uranus is best viewed after dark but before 9:00 p.m. all month. You will need a telescope to easily observe these two faint planetary disks. Find a location chart for Uranus and Neptune at this link.

4 January 2016 Sky Events the Planets The planets Jupiter, Mars, Saturn and Venus can be found all month in the south to southeast pre-dawn and dawn skies. All 4 bright planets should be very easy to spot in this early morning lineup along the ecliptic. Moving to the west side of the Sun (following its January 14 th inferior conjunction), Mercury will join Jupiter, Mars, Saturn and Venus at dawn by monthend. Find Mercury rather low in the east-southeast twilight zone during the last week of the month. This will be the first time in 11 years that all 5 visible planets will be observable simultaneously!

5 January 2016 Sky Events the Planets All month in the dawn skies, find 4 bright naked-eye planets aligned along the ecliptic. The view from Asheville, NC about one hour before sunrise on Jan. 15 th Horizon The bright stars Spica and Antares are located 263 and 604 light years, respectively, behind the planets.

6 January 2016 Sky Events Venus Passes Saturn in the Dawn Skies At dawn on January 9 th, the bright planet Venus will appear close to the fainter planet Saturn. Conjunction of Venus and Saturn In another week, Venus will appear well below Saturn, as it orbits toward the back side of the Sun, while Earth s solar orbit will cause Saturn to appear higher in the sky. Saturn is some 883 million miles behind Venus! Image courtesy of Sky & Telescope

7 January 2016 Planet Highlights Planet Avg. Distance from Earth Constellation(s) Avg. Diameter in arc seconds Avg. Magnitude Comments Page 1 of 3 Mercury 0.8 AUs Venus 1.2 AUs Mars 1.4 AUs Sagittarius & Capricornus Scorpius, Ophiuchus & Sagittarius Virgo & Libra Reaches inferior conjunction on Jan. 14 th Prominent as the morning star this month Positioned in the morning sky all month

8 January 2016 Planet Highlights Planet Avg. Distance from Earth Constellation(s) Avg. Diameter in arc seconds Avg. Magnitude Comments Page 2 of 3 Jupiter 4.8 AUs Leo Rising in the east by 9:05 p.m. at month end. Saturn 10.7 AUs Ophiuchus Can be found in the SE dawn sky all month Uranus 20 AUs Pisces Observe it early in the evening this month

9 January 2016 Planet Highlights Planet Avg. Distance from Earth Constellation(s) Avg. Diameter in arc seconds Avg. Magnitude Comments Page 3 of 3 Neptune 31 AUs Aquarius Sets soon after dusk this month

10 January 2016 Sky Events Catch all 5 Naked-eye Planets and the Moon in the Dawn Skies The view from Asheville, NC at 6:45 a.m. EST on Sunday, January 31 st, about 46 minutes before sunrise. Notice the gibbous Moon above Mars. Use binoculars to help you locate fainter Mercury near the horizon. Dawn on Jan. 31 st Horizon 5 planets from left to right along the ecliptic: Mercury, Venus, Saturn, Mars & Jupiter.

11 The Moon January 2016 Last Quarter 2 nd 12:30 a.m. New Moon 9 th 8:30 p.m. First Quarter 16 th 6:26 p.m. Full Moon** 23 rd 8:46 p.m. Last Quarter 31 st 10:28 p.m. ** The Wolf Moon Unless otherwise indicated, all times are EST

12 January 2016 Sky Events On January 2 nd, Saturday, the Earth reaches perihelion - closest approach to the Sun for the year. The word perhelion is from the Greek: peri meaning near and helios meaning Sun. Earth is some 3 million miles closer (or one part in 30 closer) at perihelion than at the farthest point in its elliptical orbit (aphelion) in early July. Yet we experience our coldest weather in the northern hemisphere during January. It s the Earth s 23½ axial tilt combined with its orbit, not its distance from the Sun, that causes the seasons. In January the northern hemisphere is pointed away from the warmth of the Sun.

13 January 2016 Sky Events Quadrantid Meteor Shower Peaks This year s Quadrantid Meteor Shower is predicted to peak in the Asheville area during the early pre-dawn hours of Monday - January 4, Under clear dark open skies, you can expect from 60 to 200 meteors per hour, but these numbers are difficult to predict reliably. A 30% illuminated waning crescent Moon will rise about 2:26 a.m. on Jan. 4 th, but it should not create a significant problem for the meteor observing. The source of this meteor shower is the debris from an object labeled 2003 EH1 an asteroid Image courtesy of Sky & Telescope or possibly an extinct comet.

14 January 2016 Sky Events the Planets Comet Catalina in the early morning skies all month Discovered in 2013 by observations of the Catalina Sky Survey, Comet C/2013 US10 (Catalina) has steadily brightened. This new comet comes from the Oort Cloud in the outer regions of the solar system. Will it become visible to the unaided eye? Comet predictions are challenging, but Catalina is presently brightening and forecasted to reach magnitude 4.8 this month visible to the naked eye under clear dark skies. Its closest approach to Earth (some 67 million miles) occurs on January 12 th. Observing Catalina will require an early rise as it will be visible in our pre-dawn/dawn skies. Comet Catalina passes very close to the bright star Arcturus in the constellation Bootes on Jan. 1. Telescopic image of Comet Catalina taken in early August 2015

15 January 2016 Sky Events the Planets Comet Catalina s path as viewed from the ecliptic plane on Jan. 12, 2016 Having rounded the Sun below the Earth s orbital plane, Comet Catalina continues its journey back to the Oort Cloud in the outer reaches of our solar system. Sun Image courtesy of Sky & Telescope

16 January 2016 Sky Events Comet Catalina s Path through the January Pre-Dawn Skies In January Comet Catalina is leaving the inner solar system, as it continues its long journey back toward the Oort Cloud. Follow this comet through our northeast skies this month. Chart courtesy of Sky & Telescope be

17 January 2016 Sky Events The view from Asheville, NC looking southeast about 6:00 a.m. EST on January 12 th Comet Catalina near the zenith in the early morning of January 12th Comet Catalina The 4 planets Jupiter, Mars, Venus & Saturn join Comet Catalina in the dawn skies. Using binoculars or a small telescope will help in locating this faint comet. The comet is located just off the end star (Alkaid) in the handle of the Big Dipper. On January 12 th Catalina is at its closest approach to Earth about 67 million miles away. Horizon Horizon Horizon

18 January 2016 Sky Events The Moon Occults the Star Aldebaran The waxing gibbous Moon will occult (pass in front of) the bright, orange, giant star Aldebaran on the night of January 19 th Tuesday. Aldebaran (in the constellation Taurus) is the brightest star that the Moon can pass across; Aldebaran shines at magnitude With binoculars or a small telescope, watch this star disappear from view behind the dark limb of the Moon about 9:21 p.m. EST, and reappear on the other side, from the illuminated limb, about 10:17 p.m. EST a 56 minute stellar blackout. These times are for Asheville, NC.

19 January 2016 Sky Events The Gibbous Moon Occults the Star Aldebaran on Tuesday, January 19th Disappearance about 9:21 p.m. Aldebaran Look to the south-southwest into the constellation Taurus to observe this event. All times are approximate for Asheville, NC using EST. Aldebaran is 65 light years behind the Moon! Reappearance about 10:17 p.m. Aldebaran

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