Post by Dave Mitsky on Dec 31, 2014 20:52:36 GMT
January Celestial Calendar by Dave Mitsky
All times are UT (subtract five hours, and one calendar day when appropriate, for EST)
1/2 The Moon is 1.4 degrees north of the first-magnitude star Aldebaran (Alpha Tauri) at 12:00; a double Galilean satellite shadow transit begins at 22:55
1/4 The latest sunrise of 2015 at latitude 40 degrees north occurs today; Pluto is in conjunction with the Sun at 0:00; the peak of the Quadrantid meteor shower (40 to 120 or more per hour) occurs at 2:00; the Earth is at perihelion (147,096,204 kilometers or 91,401,344 miles distant from the Sun) at 7:00; a double Galilean satellite shadow transit begins at 17:23
1/5 Full Moon (known as the Ice Moon, the Moon After Yule, the Old Moon, and the Wolf Moon) occurs at 4:53
1/6 A double Galilean satellite shadow transit begins at 11:56
1/8 The latest onset of morning twilight of 2015 at latitude 40 degrees north occurs today; Jupiter is 5 degrees north of the Moon at 8:00
1/9 The Moon is at apogee, subtending 29'29" minutes from a distance of 405,408 kilometers (251,909 miles), at 9:18
1/10 A double Galilean satellite shadow transit begins at 1:15
1/11 Asteroid 4 Vesta is in conjunction with the Sun at 6:00; a double Galilean satellite shadow transit begins at 21:16
1/13 Last Quarter Moon occurs at 9:46;
1/14 The Curtiss Cross, an X-shaped illumination effect located between the craters Parry and Gambart, is predicted to begin at 1:36; Mercury is at greatest eastern elongation (19.0 degrees) at 20:00
1/16 Saturn is 1.9 degrees south of the Moon at 12:00
1/17 Mercury is at the ascending node today; a double Galilean satellite shadow transit begins at 3:51
1/18 Venus is at its greatest heliocentric latitude south today
1/19 Mars is 0.2 degree south of Neptune at 21:00
1/20 New Moon (lunation 1139) occurs at 13:14; a double Galilean satellite shadow transit begins at 17:09
1/21 Mercury is at perihelion today; Mercury is stationary at 4:00; Mercury is 3 degrees south of the Moon at 18:00; the Moon is at perigee, subtending 33'14" arc minutes from a distance of 359,645 kilometers (223,473 miles), at 20:07
1/22 Venus is 6 degrees south of the Moon at 0:00
1/23 Neptune is 4 degrees south of the Moon at 1:00; Mars is 4 degrees south of the Moon at 5:00
1/24 A double Galilean satellite shadow transit begins at 4:35; a rare triple Galilean satellite shadow transit begins at 6:28; a rare triple Galilean satellite transit begins at 7:08
1/25 Uranus is 0.6 degree south of the Moon, with an occultation occurring in northern Asia, Russia, the Middle East, southern Europe, and the northern half of Africa, at 12:00
1/27 First Quarter Moon occurs at 4:48; the Lunar X (the Purbach or Werner Cross), an X-shaped illumination effect involving various rims and ridges between the craters La Caille, Blanchinus, and Purbach, is predicted to begin at 14:39; a double Galilean satellite shadow transit begins at 19:45
1/29 The Hesiodus Lunar Crater Light Ray is predicted to begin at 6:26; the Moon is 1.2 degrees north of Aldebaran, with an occultation occurring in far northern Canada, at 18:00; asteroid 3 Juno (magnitude 7.8) is at opposition at 23:00
1/30 Mercury is in inferior conjunction at 14:00
Johannes Hevelius (1611-1687) was born this month.
Galileo Galilei discovered Io, Europa, and Callisto on January 7, 1610. He discovered Ganymede on January 13, 1610. William Herschel discovered Titania and Oberon, two satellites of Uranus, on January 11, 1787. Giuseppe Piazzi discovered the first asteroid, 1 Ceres, on January 1, 1801.
The Quadrantid meteor shower peaks on the morning of January 4th. Unfortunately, the Full Moon occurs a day after the peak and will strongly interfere with observing the shower. This shower can sometimes reach zenithal hourly rates of more than 100 meteors per hour. The radiant of the Quadrantids lies at the junction of the constellations of Boötes, Hercules, and Draco, in what was once called Quadrans Muralis. The near-Earth asteroid 2003 EH1, which may be an extinct comet, is believed to be the source of these meteors. Browse meteorshowersonline.com/quadrantids.html and earthsky.org/astronomy-essentials/quadrantid-meteor-shower-before-dawn-in-early-january for more on the Quadrantids.
Information on Iridium flares and passes of the ISS, the Tiangong-1, the X-37B, the HST, and other satellites can be found at www.heavens-above.com/
The Moon is 9.9-days old, is illuminated 82.5%, and is located in Aries on January 1st at 0:00 UT. The waxing gibbous Moon enters the Hyades late on the night of January 1st-January 2nd and occults Delta 1 and/or Delta 2 Tauri from the southern and western portions of the United States. See www.lunar-occultations.com/iota/bstar/bstar.htm for information on this event. The two-day-old Moon forms a tight triangle with Mercury and Venus just after sunset on January 21st. Large tides will occur on January 21st through January 24th. The Moon attains its greatest northern declination (+18.6 degrees) for the month on January 3rd and (+18.5 degrees) on January 31st and its greatest southern declination (-18.6 degrees) on January 18th. Longitudinal libration is at a maximum of +5.3 degrees on January 1st and +6.6 degrees on January 27th and a minimum of -7.4 degrees on January 16th. Latitudinal libration is at a maximum of +6.6 degrees on January 5th and a minimum of -6.5 degrees on January 19th. Visit saberdoesthestars.wordpress.com/2011/07/05/saber-does-the-stars/ for tips on spotting extreme crescent Moons and www.curtrenz.com/moon06.html for Full Moon data. Times and dates for the lunar light rays predicted to occur this month are available at www.lunar-occultations.com/rlo/rays/rays.htm
The Sun is located in Sagittarius on January 1st.
Data (magnitude, apparent size, illumination, and distance from the Earth in astronomical units) for the planets and Pluto on January 1: Mercury (-0.8, 5.3", 91%, 1.28 a.u., Sagittarius), Venus (-3.9, 10.3", 96%, 1.62 a.u., Sagittarius), Mars (+1.1, 4.8", 94%, 1.97 a.u., Capricornus), Jupiter (-2.4, 43.4", 100%, 4.54 a.u., Leo), Saturn (+0.6, 15.5", 100%, 10.70 a.u., Libra), Uranus (+5.8, 3.5", 100%, 20.20 a.u. on December 16th, Pisces), Neptune (+7.9, 2.2", 100%, 30.71 a.u. on December 16th, Aquarius), Pluto (+14.2, 0.1", 100%, 33.76 a.u. on December 16th, Sagittarius).
During the evening, Mercury, Venus, Mars, and Neptune lie in the southwest and Uranus in the south. At midnight, Jupiter is in the southeast. Jupiter can be seen in the west and Saturn in the southeast in the morning.
At midmonth, Mercury is visible during evening twilight, Venus sets at 7:00 p.m., Mars sets at 8:00 p.m., Jupiter rises at 7:00 p.m. and transits the meridian at 2:00 a.m., and Saturn rises at 3:00 a.m. local time for observers at latitude 40 degrees north.
One hour after sunset on January 23rd, Mercury and Venus lie close to the horizon, while Neptune, Mars, and the thin crescent Moon are positioned to their upper left. Uranus is located about as far to the upper left of the Moon as Venus is to the lower right.
Although Mercury never reaches more than seven degrees above the horizon for observers in mid-northern latitudes, it is still the second highest evening apparition of the planet this year. Mercury is less than one degree from Venus from January 8th to January 12th. The speediest planet reaches greatest eastern elongation on January 14th and perihelion on January 21st. It is 3 degrees south of the Moon on January 21st. Mercury dims from magnitude -0.8 on January 1st to magnitude +1.4 on January 23rd. It is in inferior conjunction on January 30th.
Venus shines at magnitude -3.9 throughout January. Venus and Mercury lie within one degree of each other from January 8th through January 12th. A close quasi-conjunction, the first quasi-conjunction of bright planets since 2012 and the closest encounter of Mercury and Venus since 2001, takes place at 7:00 p.m. EST on January 10th, when the two planets are separated by only 39 arc minutes. Venus is about six degrees from Mercury on the evening of January 21st and six degrees from the Moon later that night.
Earth is 0.983 astronomical units distant from the Sun at perihelion on January 4th. On that date, it’s about 3% (5.0 million kilometers or 3.1 million miles) closer to the Sun than at aphelion.
Mars departs Capricornus and enters Aquarius on January 9th. The Red Planet is now a miniscule four arc seconds in size. Mars (magnitude +1.1) passes 0.2 degree south of Neptune (magnitude +7.9) on January 19th.
During January, Jupiter’s disk increases in size by 1.9 arc seconds. It brightens from magnitude -2.4 to magnitude -2.6. The angular distance between Jupiter and the first-magnitude star Regulus (Alpha Leonis) increases from eight to twelve degrees this month. The waning gibbous Moon passes five degrees south of Jupiter on January 8th. Click on www.skyandtelescope.com/observing/interactive-sky-watching-tools/ or consult page 53 of the January issue of Sky & Telescope to determine transit times of the central meridian by the Great Red Spot. Data on Galilean satellite events is available online at www.shallowsky.com/jupiter/ and www.skyandtelescope.com/observing/interactive-sky-watching-tools/ and on page 53 of the January issue of Sky & Telescope. A rare triple Galilean satellite shadow transit occurs on the night of January 23rd-January 24th. Callisto’s shadow ingresses at 10:11 p.m. EST, Io’s at 11:35 p.m. EST, and Europa’s at 1:28 a.m. EST. All three shadows are then visible for 25 minutes. The three satellites themselves are in transit simultaneously from 2:08 to 2:12 a.m. EST. Another triple transit won’t take place until 2032. Mutual events of the Jovian moons visible from North America take place on January 15th, January 19th, January 23rd, January 26th, January 28th, and January 29th. For further information on these events, consult www.skyandtelescope.com/sky-and-telescope-magazine/beyond-the-printed-page/mutual-events-jupiters-satellites-201415/ and page 52 of the January issue of Sky & Telescope.
Saturn rises after 4:00 a.m. local time at the start of January. On January 16th, a crescent Moon passes two degrees north of Saturn. Saturn leaves Libra and heads into Scorpius on January 17th. Saturn’s rings are inclined some 24 degrees with respect to the Earth this month. During 2015, the northern side of Saturn’s rings is visible. The planet’s disk subtends 16 arc seconds and its rings span 36 arc seconds. (Saturn’s rings are 2.27 times larger in extent than the planet’s equatorial diameter.) For information on the satellites of Saturn, browse www.skyandtelescope.com/observing/interactive-sky-watching-tools/
Uranus can be found 3.2 degrees south of the fourth-magnitude star Delta Piscium in southern Pisces. The first of twelve occultations of Uranus by the Moon occurring this year takes place on January 25th.
Neptune is located low in the western sky at sunset. It has close encounters with Mars on the evening of January 19th and Venus on January 31st at twilight.
Finder charts for Uranus and Neptune can be found at www.skyandtelescope.com/wp-content/uploads/WEB_Uranus_Neptune_2014.pdf and on page 51 of the September issue of Sky & Telescope. See www.curtrenz.com/uranep.html for additional information on the two outer planets.
The dwarf planet Pluto is in conjunction with the Sun on January 4th UT.
For more on the planets and how to locate them, browse www.nakedeyeplanets.com/
The NEO 2004 BL86 (asteroid 357439) will pass within pass within 1,200,000 kilometers (750,000 miles) of the Earth at 16:00 UT (11:00 a.m. EST) on January 26th. Observers in North and South America, Europe, and Africa will have the best views of 2004 BL86 when it is at its brightest, from 1:00 to 6:00 UT (8:00 p.m. to 1:00 a.m. EST) on January 27th. During that time, it will be heading northeastward through Cancer and will pass through the eastern boundary of M44 at 5:00 UT (12:00 a.m. EST). The asteroid should be visible through a 3 or 4-inch aperture. 2004 BL86 will be traveling at approximately two arc seconds per second or two degrees per hour so its motion will be apparent in real time. For additional information on the event and a finder chart, see pages 50 and 51 of the February issue of Sky & Telescope. Asteroid 3 Juno travels northwestward through northern Hydra this month. Juno, which is the smallest of the first four asteroids to be discovered, shines at magnitude +8.1 when it reaches opposition on January 29th. Click on in-the-sky.org/news.php?id=20150130_14_100 for a finder chart and an ephemeris. Other asteroids coming to opposition this month include 94 Aurora (magnitude 12.1) on January 2nd, 69 Hesperia (magnitude 10.6) on January 16th, and 42 Isis (magnitude 12.0) on January 31st. Consult www.curtrenz.com/asteroids to learn more about a number of asteroids. Occultations of eighth-to-tenth-magnitude stars by the faint asteroids 1333 Cevenola, 753 Tiflis, 110 Lydia, and 166 Rhodope are visible from various locations in the United States and Canada this month. Browse asteroidoccultation.com/2015_01_si.htm for information on these asteroid occultations.
Comet C/2014 Q2 (Lovejoy) brightens to fourth magnitude and should be readily visible to the naked-eye from a dark site, as it heads northwestward through Lepus, Eridanus, Taurus, Aries, Triangulum, and Andromeda. Browse www.skyandtelescope.com/astronomy-news/observing-news/binocular-comet-lovejoy-heading-c2014-q2-lovejoy-1211142/ and in-the-sky.org/cometephem.php for more on Comet Lovejoy. Visit cometchasing.skyhound.com/ and www.aerith.net/comet/future-n.html for information on comets visible this month and in the near future.
A wealth of information on solar system celestial bodies is posted at www.curtrenz.com/astronomical
Click on astrocast.tv/ for an informative video on astronomical events taking place this month.
Free star maps for January can be downloaded at www.skymaps.com/downloads.html and www.telescope.com/content.jsp?pageName=Monthly-Star-Chart
Omicron2 (40) Eridani is a fourth-magnitude triple star system consisting of three dwarf stars: a type K1V yellow-orange dwarf (A) known as Keid, a type DA4 white dwarf (B), and a type M4.5e red dwarf (C). Omicron is located about 16 light years from the Earth at 4h15m16.32s, -7°39′10.34″. Ninth-magnitude Omicron B is the most easily visible white dwarf star and can be seen with an aperture of 6 inches.
During January, the Mira-type variable star R Geminorum brightens by about two magnitudes. A finder chart for the spectral type S star can be found on page 51 of the January issue of Sky & Telescope.
An eclipse of the fourth-magnitude visual binary star Alpha Comae Berenices may take place around January 25th, with January 23rd and January 24th being likely dates. A central eclipse would mean a drop of about eight-tenths of a magnitude for several hours. See www.aavso.org/observing-campaign-alf-Com and page 50 of the January issue of Sky & Telescope for additional information on this rare event.
The famous eclipsing variable star Algol (Beta Persei) is at a minimum, decreasing in magnitude from 2.1 to 3.4, on January 2nd, 5th, 8th, 10th, 13th, 16th, 19th, 22nd, 25th, 28th and 31st. Consult page 51 of the January issue of Sky & Telescope for the times of the minima. For more on Algol, see stars.astro.illinois.edu/sow/Algol.html and www.solstation.com/stars2/algol3.htm
One hundred and five binary and multiple stars for January: Omega Aurigae, 5 Aurigae, Struve 644, 14 Aurigae, Struve 698, Struve 718, 26 Aurigae, Struve 764, Struve 796, Struve 811, Theta Aurigae (Auriga); Struve 485, 1 Camelopardalis, Struve 587, Beta Camelopardalis, 11 & 12 Camelopardalis, Struve 638, Struve 677, 29 Camelopardalis, Struve 780 (Camelopardalis); h3628, Struve 560, Struve 570, Struve 571, Struve 576, 55 Eridani, Struve 596, Struve 631, Struve 636, 66 Eridani, Struve 649 (Eridanus); Kappa Leporis, South 473, South 476, h3750, h3752, h3759, Beta Leporis, Alpha Leporis, h3780, Lallande 1, h3788, Gamma Leporis (Lepus); Struve 627, Struve 630, Struve 652, Phi Orionis, Otto Struve 517, Beta Orionis (Rigel), Struve 664, Tau Orionis, Burnham 189, h697, Struve 701, Eta Orionis, h2268, 31 Orionis, 33 Orionis, Delta Orionis (Mintaka), Struve 734, Struve 747, Lambda Orionis, Theta-1 Orionis (the Trapezium), Theta-2 Orionis, Iota Orionis, Struve 750, Struve 754, Sigma Orionis, Zeta Orionis (Alnitak), Struve 790, 52 Orionis, Struve 816, 59 Orionis, 60 Orionis (Orion); Struve 476, Espin 878, Struve 521, Struve 533, 56 Persei, Struve 552, 57 Persei (Perseus); Struve 479, Otto Struve 70, Struve 495, Otto Struve 72, Struve 510, 47 Tauri, Struve 517, Struve 523, Phi Tauri, Burnham 87, Xi Tauri, 62 Tauri, Kappa & 67 Tauri, Struve 548, Otto Struve 84, Struve 562, 88 Tauri, Struve 572, Tau Tauri, Struve 598, Struve 623, Struve 645, Struve 670, Struve 674, Struve 680, 111 Tauri, 114 Tauri, 118 Tauri, Struve 730, Struve 742, 133 Tauri (Taurus)
Notable carbon star for January: R Leporis (Hind’s Crimson Star)
Seventy deep-sky objects for January: B26-28, B29, M36, M37, M38, NGC 1664, NGC 1778, NGC 1857, NGC 1893, NGC 1907, NGC 1931 (Auriga); IC 361, Kemble 1 (Kemble’s Cascade asterism), NGC 1501, NGC 1502, NGC 1530, NGC 1569 (Camelopardalis); NGC 1507, NGC 1518, NGC 1531, NGC 1532, NGC 1535, NGC 1537, NGC 1600, NGC 1637, NGC 1659, NGC 1700 (Eridanus); IC 418, M79, NGC 1832, NGC 1888, NGC 1964 (Lepus); B33, Cr65, Cr69, Cr70, IC 434, M42, M43, M78, NGC 1662, NGC 1973-75-77, NGC 1981, NGC 1999, NGC 2022, NGC 2023, NGC 2024, NGC 2112 (Orion); Be11, NGC 1491, NGC 1496, NGC 1499, NGC 1513, NGC 1528, NGC 1545, NGC 1548, NGC 1579, NGC 1582, NGC 1605, NGC 1624 (Perseus); DoDz3, DoDz4, M1, Mel 25, NGC 1514, NGC 1587, NGC 1647, NGC 1746, NGC 1807, NGC 1817 (Taurus)
Top ten binocular deep-sky objects for January: Cr65, Kemble 1, M36, M37, M38, M42, NGC 1528, NGC 1647, NGC 1746, NGC 1981
Top ten deep-sky objects for January: M1, M36, M37, M38, M42, M43, M78, M79, NGC 1501, NGC 2024
Challenge deep-sky object for January: IC 2118 (Eridanus)
The objects listed above are located between 4:00 and 6:00 hours of right ascension.
All times are UT (subtract five hours, and one calendar day when appropriate, for EST)
1/2 The Moon is 1.4 degrees north of the first-magnitude star Aldebaran (Alpha Tauri) at 12:00; a double Galilean satellite shadow transit begins at 22:55
1/4 The latest sunrise of 2015 at latitude 40 degrees north occurs today; Pluto is in conjunction with the Sun at 0:00; the peak of the Quadrantid meteor shower (40 to 120 or more per hour) occurs at 2:00; the Earth is at perihelion (147,096,204 kilometers or 91,401,344 miles distant from the Sun) at 7:00; a double Galilean satellite shadow transit begins at 17:23
1/5 Full Moon (known as the Ice Moon, the Moon After Yule, the Old Moon, and the Wolf Moon) occurs at 4:53
1/6 A double Galilean satellite shadow transit begins at 11:56
1/8 The latest onset of morning twilight of 2015 at latitude 40 degrees north occurs today; Jupiter is 5 degrees north of the Moon at 8:00
1/9 The Moon is at apogee, subtending 29'29" minutes from a distance of 405,408 kilometers (251,909 miles), at 9:18
1/10 A double Galilean satellite shadow transit begins at 1:15
1/11 Asteroid 4 Vesta is in conjunction with the Sun at 6:00; a double Galilean satellite shadow transit begins at 21:16
1/13 Last Quarter Moon occurs at 9:46;
1/14 The Curtiss Cross, an X-shaped illumination effect located between the craters Parry and Gambart, is predicted to begin at 1:36; Mercury is at greatest eastern elongation (19.0 degrees) at 20:00
1/16 Saturn is 1.9 degrees south of the Moon at 12:00
1/17 Mercury is at the ascending node today; a double Galilean satellite shadow transit begins at 3:51
1/18 Venus is at its greatest heliocentric latitude south today
1/19 Mars is 0.2 degree south of Neptune at 21:00
1/20 New Moon (lunation 1139) occurs at 13:14; a double Galilean satellite shadow transit begins at 17:09
1/21 Mercury is at perihelion today; Mercury is stationary at 4:00; Mercury is 3 degrees south of the Moon at 18:00; the Moon is at perigee, subtending 33'14" arc minutes from a distance of 359,645 kilometers (223,473 miles), at 20:07
1/22 Venus is 6 degrees south of the Moon at 0:00
1/23 Neptune is 4 degrees south of the Moon at 1:00; Mars is 4 degrees south of the Moon at 5:00
1/24 A double Galilean satellite shadow transit begins at 4:35; a rare triple Galilean satellite shadow transit begins at 6:28; a rare triple Galilean satellite transit begins at 7:08
1/25 Uranus is 0.6 degree south of the Moon, with an occultation occurring in northern Asia, Russia, the Middle East, southern Europe, and the northern half of Africa, at 12:00
1/27 First Quarter Moon occurs at 4:48; the Lunar X (the Purbach or Werner Cross), an X-shaped illumination effect involving various rims and ridges between the craters La Caille, Blanchinus, and Purbach, is predicted to begin at 14:39; a double Galilean satellite shadow transit begins at 19:45
1/29 The Hesiodus Lunar Crater Light Ray is predicted to begin at 6:26; the Moon is 1.2 degrees north of Aldebaran, with an occultation occurring in far northern Canada, at 18:00; asteroid 3 Juno (magnitude 7.8) is at opposition at 23:00
1/30 Mercury is in inferior conjunction at 14:00
Johannes Hevelius (1611-1687) was born this month.
Galileo Galilei discovered Io, Europa, and Callisto on January 7, 1610. He discovered Ganymede on January 13, 1610. William Herschel discovered Titania and Oberon, two satellites of Uranus, on January 11, 1787. Giuseppe Piazzi discovered the first asteroid, 1 Ceres, on January 1, 1801.
The Quadrantid meteor shower peaks on the morning of January 4th. Unfortunately, the Full Moon occurs a day after the peak and will strongly interfere with observing the shower. This shower can sometimes reach zenithal hourly rates of more than 100 meteors per hour. The radiant of the Quadrantids lies at the junction of the constellations of Boötes, Hercules, and Draco, in what was once called Quadrans Muralis. The near-Earth asteroid 2003 EH1, which may be an extinct comet, is believed to be the source of these meteors. Browse meteorshowersonline.com/quadrantids.html and earthsky.org/astronomy-essentials/quadrantid-meteor-shower-before-dawn-in-early-january for more on the Quadrantids.
Information on Iridium flares and passes of the ISS, the Tiangong-1, the X-37B, the HST, and other satellites can be found at www.heavens-above.com/
The Moon is 9.9-days old, is illuminated 82.5%, and is located in Aries on January 1st at 0:00 UT. The waxing gibbous Moon enters the Hyades late on the night of January 1st-January 2nd and occults Delta 1 and/or Delta 2 Tauri from the southern and western portions of the United States. See www.lunar-occultations.com/iota/bstar/bstar.htm for information on this event. The two-day-old Moon forms a tight triangle with Mercury and Venus just after sunset on January 21st. Large tides will occur on January 21st through January 24th. The Moon attains its greatest northern declination (+18.6 degrees) for the month on January 3rd and (+18.5 degrees) on January 31st and its greatest southern declination (-18.6 degrees) on January 18th. Longitudinal libration is at a maximum of +5.3 degrees on January 1st and +6.6 degrees on January 27th and a minimum of -7.4 degrees on January 16th. Latitudinal libration is at a maximum of +6.6 degrees on January 5th and a minimum of -6.5 degrees on January 19th. Visit saberdoesthestars.wordpress.com/2011/07/05/saber-does-the-stars/ for tips on spotting extreme crescent Moons and www.curtrenz.com/moon06.html for Full Moon data. Times and dates for the lunar light rays predicted to occur this month are available at www.lunar-occultations.com/rlo/rays/rays.htm
The Sun is located in Sagittarius on January 1st.
Data (magnitude, apparent size, illumination, and distance from the Earth in astronomical units) for the planets and Pluto on January 1: Mercury (-0.8, 5.3", 91%, 1.28 a.u., Sagittarius), Venus (-3.9, 10.3", 96%, 1.62 a.u., Sagittarius), Mars (+1.1, 4.8", 94%, 1.97 a.u., Capricornus), Jupiter (-2.4, 43.4", 100%, 4.54 a.u., Leo), Saturn (+0.6, 15.5", 100%, 10.70 a.u., Libra), Uranus (+5.8, 3.5", 100%, 20.20 a.u. on December 16th, Pisces), Neptune (+7.9, 2.2", 100%, 30.71 a.u. on December 16th, Aquarius), Pluto (+14.2, 0.1", 100%, 33.76 a.u. on December 16th, Sagittarius).
During the evening, Mercury, Venus, Mars, and Neptune lie in the southwest and Uranus in the south. At midnight, Jupiter is in the southeast. Jupiter can be seen in the west and Saturn in the southeast in the morning.
At midmonth, Mercury is visible during evening twilight, Venus sets at 7:00 p.m., Mars sets at 8:00 p.m., Jupiter rises at 7:00 p.m. and transits the meridian at 2:00 a.m., and Saturn rises at 3:00 a.m. local time for observers at latitude 40 degrees north.
One hour after sunset on January 23rd, Mercury and Venus lie close to the horizon, while Neptune, Mars, and the thin crescent Moon are positioned to their upper left. Uranus is located about as far to the upper left of the Moon as Venus is to the lower right.
Although Mercury never reaches more than seven degrees above the horizon for observers in mid-northern latitudes, it is still the second highest evening apparition of the planet this year. Mercury is less than one degree from Venus from January 8th to January 12th. The speediest planet reaches greatest eastern elongation on January 14th and perihelion on January 21st. It is 3 degrees south of the Moon on January 21st. Mercury dims from magnitude -0.8 on January 1st to magnitude +1.4 on January 23rd. It is in inferior conjunction on January 30th.
Venus shines at magnitude -3.9 throughout January. Venus and Mercury lie within one degree of each other from January 8th through January 12th. A close quasi-conjunction, the first quasi-conjunction of bright planets since 2012 and the closest encounter of Mercury and Venus since 2001, takes place at 7:00 p.m. EST on January 10th, when the two planets are separated by only 39 arc minutes. Venus is about six degrees from Mercury on the evening of January 21st and six degrees from the Moon later that night.
Earth is 0.983 astronomical units distant from the Sun at perihelion on January 4th. On that date, it’s about 3% (5.0 million kilometers or 3.1 million miles) closer to the Sun than at aphelion.
Mars departs Capricornus and enters Aquarius on January 9th. The Red Planet is now a miniscule four arc seconds in size. Mars (magnitude +1.1) passes 0.2 degree south of Neptune (magnitude +7.9) on January 19th.
During January, Jupiter’s disk increases in size by 1.9 arc seconds. It brightens from magnitude -2.4 to magnitude -2.6. The angular distance between Jupiter and the first-magnitude star Regulus (Alpha Leonis) increases from eight to twelve degrees this month. The waning gibbous Moon passes five degrees south of Jupiter on January 8th. Click on www.skyandtelescope.com/observing/interactive-sky-watching-tools/ or consult page 53 of the January issue of Sky & Telescope to determine transit times of the central meridian by the Great Red Spot. Data on Galilean satellite events is available online at www.shallowsky.com/jupiter/ and www.skyandtelescope.com/observing/interactive-sky-watching-tools/ and on page 53 of the January issue of Sky & Telescope. A rare triple Galilean satellite shadow transit occurs on the night of January 23rd-January 24th. Callisto’s shadow ingresses at 10:11 p.m. EST, Io’s at 11:35 p.m. EST, and Europa’s at 1:28 a.m. EST. All three shadows are then visible for 25 minutes. The three satellites themselves are in transit simultaneously from 2:08 to 2:12 a.m. EST. Another triple transit won’t take place until 2032. Mutual events of the Jovian moons visible from North America take place on January 15th, January 19th, January 23rd, January 26th, January 28th, and January 29th. For further information on these events, consult www.skyandtelescope.com/sky-and-telescope-magazine/beyond-the-printed-page/mutual-events-jupiters-satellites-201415/ and page 52 of the January issue of Sky & Telescope.
Saturn rises after 4:00 a.m. local time at the start of January. On January 16th, a crescent Moon passes two degrees north of Saturn. Saturn leaves Libra and heads into Scorpius on January 17th. Saturn’s rings are inclined some 24 degrees with respect to the Earth this month. During 2015, the northern side of Saturn’s rings is visible. The planet’s disk subtends 16 arc seconds and its rings span 36 arc seconds. (Saturn’s rings are 2.27 times larger in extent than the planet’s equatorial diameter.) For information on the satellites of Saturn, browse www.skyandtelescope.com/observing/interactive-sky-watching-tools/
Uranus can be found 3.2 degrees south of the fourth-magnitude star Delta Piscium in southern Pisces. The first of twelve occultations of Uranus by the Moon occurring this year takes place on January 25th.
Neptune is located low in the western sky at sunset. It has close encounters with Mars on the evening of January 19th and Venus on January 31st at twilight.
Finder charts for Uranus and Neptune can be found at www.skyandtelescope.com/wp-content/uploads/WEB_Uranus_Neptune_2014.pdf and on page 51 of the September issue of Sky & Telescope. See www.curtrenz.com/uranep.html for additional information on the two outer planets.
The dwarf planet Pluto is in conjunction with the Sun on January 4th UT.
For more on the planets and how to locate them, browse www.nakedeyeplanets.com/
The NEO 2004 BL86 (asteroid 357439) will pass within pass within 1,200,000 kilometers (750,000 miles) of the Earth at 16:00 UT (11:00 a.m. EST) on January 26th. Observers in North and South America, Europe, and Africa will have the best views of 2004 BL86 when it is at its brightest, from 1:00 to 6:00 UT (8:00 p.m. to 1:00 a.m. EST) on January 27th. During that time, it will be heading northeastward through Cancer and will pass through the eastern boundary of M44 at 5:00 UT (12:00 a.m. EST). The asteroid should be visible through a 3 or 4-inch aperture. 2004 BL86 will be traveling at approximately two arc seconds per second or two degrees per hour so its motion will be apparent in real time. For additional information on the event and a finder chart, see pages 50 and 51 of the February issue of Sky & Telescope. Asteroid 3 Juno travels northwestward through northern Hydra this month. Juno, which is the smallest of the first four asteroids to be discovered, shines at magnitude +8.1 when it reaches opposition on January 29th. Click on in-the-sky.org/news.php?id=20150130_14_100 for a finder chart and an ephemeris. Other asteroids coming to opposition this month include 94 Aurora (magnitude 12.1) on January 2nd, 69 Hesperia (magnitude 10.6) on January 16th, and 42 Isis (magnitude 12.0) on January 31st. Consult www.curtrenz.com/asteroids to learn more about a number of asteroids. Occultations of eighth-to-tenth-magnitude stars by the faint asteroids 1333 Cevenola, 753 Tiflis, 110 Lydia, and 166 Rhodope are visible from various locations in the United States and Canada this month. Browse asteroidoccultation.com/2015_01_si.htm for information on these asteroid occultations.
Comet C/2014 Q2 (Lovejoy) brightens to fourth magnitude and should be readily visible to the naked-eye from a dark site, as it heads northwestward through Lepus, Eridanus, Taurus, Aries, Triangulum, and Andromeda. Browse www.skyandtelescope.com/astronomy-news/observing-news/binocular-comet-lovejoy-heading-c2014-q2-lovejoy-1211142/ and in-the-sky.org/cometephem.php for more on Comet Lovejoy. Visit cometchasing.skyhound.com/ and www.aerith.net/comet/future-n.html for information on comets visible this month and in the near future.
A wealth of information on solar system celestial bodies is posted at www.curtrenz.com/astronomical
Click on astrocast.tv/ for an informative video on astronomical events taking place this month.
Free star maps for January can be downloaded at www.skymaps.com/downloads.html and www.telescope.com/content.jsp?pageName=Monthly-Star-Chart
Omicron2 (40) Eridani is a fourth-magnitude triple star system consisting of three dwarf stars: a type K1V yellow-orange dwarf (A) known as Keid, a type DA4 white dwarf (B), and a type M4.5e red dwarf (C). Omicron is located about 16 light years from the Earth at 4h15m16.32s, -7°39′10.34″. Ninth-magnitude Omicron B is the most easily visible white dwarf star and can be seen with an aperture of 6 inches.
During January, the Mira-type variable star R Geminorum brightens by about two magnitudes. A finder chart for the spectral type S star can be found on page 51 of the January issue of Sky & Telescope.
An eclipse of the fourth-magnitude visual binary star Alpha Comae Berenices may take place around January 25th, with January 23rd and January 24th being likely dates. A central eclipse would mean a drop of about eight-tenths of a magnitude for several hours. See www.aavso.org/observing-campaign-alf-Com and page 50 of the January issue of Sky & Telescope for additional information on this rare event.
The famous eclipsing variable star Algol (Beta Persei) is at a minimum, decreasing in magnitude from 2.1 to 3.4, on January 2nd, 5th, 8th, 10th, 13th, 16th, 19th, 22nd, 25th, 28th and 31st. Consult page 51 of the January issue of Sky & Telescope for the times of the minima. For more on Algol, see stars.astro.illinois.edu/sow/Algol.html and www.solstation.com/stars2/algol3.htm
One hundred and five binary and multiple stars for January: Omega Aurigae, 5 Aurigae, Struve 644, 14 Aurigae, Struve 698, Struve 718, 26 Aurigae, Struve 764, Struve 796, Struve 811, Theta Aurigae (Auriga); Struve 485, 1 Camelopardalis, Struve 587, Beta Camelopardalis, 11 & 12 Camelopardalis, Struve 638, Struve 677, 29 Camelopardalis, Struve 780 (Camelopardalis); h3628, Struve 560, Struve 570, Struve 571, Struve 576, 55 Eridani, Struve 596, Struve 631, Struve 636, 66 Eridani, Struve 649 (Eridanus); Kappa Leporis, South 473, South 476, h3750, h3752, h3759, Beta Leporis, Alpha Leporis, h3780, Lallande 1, h3788, Gamma Leporis (Lepus); Struve 627, Struve 630, Struve 652, Phi Orionis, Otto Struve 517, Beta Orionis (Rigel), Struve 664, Tau Orionis, Burnham 189, h697, Struve 701, Eta Orionis, h2268, 31 Orionis, 33 Orionis, Delta Orionis (Mintaka), Struve 734, Struve 747, Lambda Orionis, Theta-1 Orionis (the Trapezium), Theta-2 Orionis, Iota Orionis, Struve 750, Struve 754, Sigma Orionis, Zeta Orionis (Alnitak), Struve 790, 52 Orionis, Struve 816, 59 Orionis, 60 Orionis (Orion); Struve 476, Espin 878, Struve 521, Struve 533, 56 Persei, Struve 552, 57 Persei (Perseus); Struve 479, Otto Struve 70, Struve 495, Otto Struve 72, Struve 510, 47 Tauri, Struve 517, Struve 523, Phi Tauri, Burnham 87, Xi Tauri, 62 Tauri, Kappa & 67 Tauri, Struve 548, Otto Struve 84, Struve 562, 88 Tauri, Struve 572, Tau Tauri, Struve 598, Struve 623, Struve 645, Struve 670, Struve 674, Struve 680, 111 Tauri, 114 Tauri, 118 Tauri, Struve 730, Struve 742, 133 Tauri (Taurus)
Notable carbon star for January: R Leporis (Hind’s Crimson Star)
Seventy deep-sky objects for January: B26-28, B29, M36, M37, M38, NGC 1664, NGC 1778, NGC 1857, NGC 1893, NGC 1907, NGC 1931 (Auriga); IC 361, Kemble 1 (Kemble’s Cascade asterism), NGC 1501, NGC 1502, NGC 1530, NGC 1569 (Camelopardalis); NGC 1507, NGC 1518, NGC 1531, NGC 1532, NGC 1535, NGC 1537, NGC 1600, NGC 1637, NGC 1659, NGC 1700 (Eridanus); IC 418, M79, NGC 1832, NGC 1888, NGC 1964 (Lepus); B33, Cr65, Cr69, Cr70, IC 434, M42, M43, M78, NGC 1662, NGC 1973-75-77, NGC 1981, NGC 1999, NGC 2022, NGC 2023, NGC 2024, NGC 2112 (Orion); Be11, NGC 1491, NGC 1496, NGC 1499, NGC 1513, NGC 1528, NGC 1545, NGC 1548, NGC 1579, NGC 1582, NGC 1605, NGC 1624 (Perseus); DoDz3, DoDz4, M1, Mel 25, NGC 1514, NGC 1587, NGC 1647, NGC 1746, NGC 1807, NGC 1817 (Taurus)
Top ten binocular deep-sky objects for January: Cr65, Kemble 1, M36, M37, M38, M42, NGC 1528, NGC 1647, NGC 1746, NGC 1981
Top ten deep-sky objects for January: M1, M36, M37, M38, M42, M43, M78, M79, NGC 1501, NGC 2024
Challenge deep-sky object for January: IC 2118 (Eridanus)
The objects listed above are located between 4:00 and 6:00 hours of right ascension.