Post by Dave Mitsky on Dec 30, 2018 23:12:21 GMT
January Celestial Calendar by Dave Mitsky
All times are UT (subtract five hours, and one calendar day when appropriate, for EST)
1/1 The Moon is 1.3 degrees north of Venus at 22:00
1/2 Mercury is at the descending node through the ecliptic plane at 0:00; Mars crosses north of the celestial equator at 1:00; Saturn is in conjunction with the Sun at 6:00
1/3 The Moon is 8.4 degrees north-northeast of first-magnitude star Antares (Alpha Scorpii) at 5:00; the Earth is at perihelion (147,099,761 kilometers or 91,403,554 miles distant from the Sun) at 5:20; the Moon is 3.1 degrees north-northeast of Jupiter at 10:00
1/4 The latest sunrise of 2019 at latitude 40 degrees north occurs today; the peak of the Quadrantid meteor shower (40 to 120 or more per hour) is predicted to occur at 2:30; the Moon is 2.8 degrees north of Mercury at 19:00
1/5 The Moon is 0.9 degree north of Saturn at 19:00; Venus is at dichotomy (50% illuminated) at 19:00; a partial solar eclipse visible from China, Korea, Japan, Russia, the northern Pacific Ocean, and the Aleutian Islands begins at 23:34
1/6 New Moon (lunation 1188) occurs at 1:28; the instant of greatest eclipse for the ongoing partial solar eclipse takes place at 01:41; the partial solar eclipse ends at 3:48; Venus is at greatest western elongation (46.9 degrees) at 5:00; Uranus is stationary in longitude at 18:00
1/7 Uranus is stationary in right ascension, with direct motion to resume, at 0:00; the Moon is at descending node (longitude 296.7 degrees) at 0:08; the Moon displays minimum libration for the year (1.2 degrees) at 15:00
1/8 The latest onset of morning twilight of 2019 at latitude 40 degrees north occurs today
1/9 The Moon is at apogee, subtending 29' 25" from a distance of 406,117 kilometers (252,850 miles), at 4:00
1/10 Mercury is at its southernmost declination (-24.1 degrees) at 18:00; the Moon is 3.0 degrees south of Neptune at 22:00
1/11 Pluto is in conjunction with the Sun at 12:00
1/12 Mercury is at aphelion (0.4667 a.u. from the Sun) at 8:00
1/13 The Moon is 5.0 degrees south-southeast of Mars at 1:00; Mercury (magnitude -0.6) is 1.7 degrees south of Saturn (magnitude +0.5) at 12:00; 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 be fully formed at approximately 12:35
1/14 First Quarter Moon occurs at 6:46; the Moon is 4.8 degrees south-southeast of Uranus at 17:00
1/15 Mars is at the ascending node through the ecliptic plane at 5:00
1/16 Venus (magnitude -4.4) is 7.8 degrees north of the first-magnitude star Antares at 23:00
1/17 The Moon is 8.5 degrees south-southeast of the bright open cluster M45 (the Pleiades or Subaru) in Taurus at 3:00; the middle of the eclipse season (the Sun is at same longitude as the descending node of the Moon, 296.7 degrees) occurs at 8:00; Venus is at its northernmost latitude from the ecliptic plane (3.4 degrees) at 8:00; the Moon is 1.6 degrees north of the first magnitude star Aldebaran (Alpha Tauri) at 19:00
1/18 Mercury (magnitude -0.8) is 1.5 degrees south of Pluto (magnitude +14.3) at 20:00
1/19 Uranus is at eastern quadrature (90 degrees from the Sun) at 1:00
1/20 The Sun enters Capricornus (ecliptic longitude 299.7 degrees) at 2:00; the Moon is 7.0 degrees south of the first-magnitude star Pollux (Beta Geminorum) at 19:00; the Moon is at the ascending node (longitude 116.8 degrees) at 22:48
1/21 A partial lunar eclipse begins at 3:34; the instant of greatest eclipse occurs at 5:12; Full Moon (known as the Ice Moon, the Moon after Yule, the Old Moon, and the Wolf Moon) occurs at 5:16; the partial lunar eclipse ends at 6:51; the Moon is 0.6 degree south of the bright open cluster M44 (the Beehive Cluster or Praesepe) in Cancer at 15:32; the Moon is at perigee (just 14.7 hours after Full Moon), subtending 33' 26" from a distance of 357,342 kilometers (222,042 miles), at 20:00
1/22 Venus (magnitude -4.3) is 2.4 degrees north of Jupiter (magnitude -1.8) at 16:00
1/23 The Moon is 2.5 degrees north-northeast of the first-magnitude star Regulus (Alpha Leonis) at 4:00
1/26 The Moon is 7.3 degrees north-northeast of the first-magnitude star Spica (Alpha Virginis), at 21:00
1/27 The Moon displays maximum libration for the year (10.1 degrees) at 17:00; Last Quarter Moon occurs at 21:10
1/29 The Curtiss Cross, an X-shaped clair-obscure illumination effect located between the craters Parry and Gambart, is predicted to be fully formed at 15:54
1/30 Mercury is at superior conjunction with the Sun (latitude -6.9 degrees) at 3:00; the Moon is 8.4 degrees north-northeast of Antares at 11:00
1/31 The Moon is 2.7 degrees north-northeast of Jupiter at 2:00; the Moon is 0.1 degree east-northeast of Venus, with an occultation occurring in western South America and Polynesia, at 18:00
Johannes Hevelius (1611-1687), Ernst Abbe (1840-1905), George Van Biesbroeck (1880-1974), Luboš Kohoutek (1935), and Stephen Hawking (1942) were born this month.
Galileo Galilei discovered Io, Europa, and Callisto on January 7, 1610. Galileo Galilei discovered Ganymede on January 13, 1610. Nicolas-Louis de Lacaille discovered the emission nebula NGC 3372 (the Eta Carinae Nebula) on January 25, 1752. Charles Messier discovered the globular cluster M56 on January 23, 1779. Charles Messier discovered the globular cluster M80 on January 4, 1781. William Herschel discovered the spiral galaxy NGC 1084 on January 10, 1785. Pierre François André Méchain discovered Comet 2P/Encke on January 17, 1786. 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. Louis Daguerre took the first photograph of the Moon on January 2, 1839. Alvan Clark discovered the white dwarf star Sirius B (the Pup) on January 31, 1862. The 36-inch Clark refractor at the Lick Observatory saw first light on January 3, 1888. Charles Perrine discovered the Jovian satellite Elara on January 2, 1905. Philibert Jacques Melotte discovered the Jovian satellite Pasiphae on January 27, 1908. Clyde Tombaugh photographed Pluto on January 23, 1930. Mike Brown, Chad Trujillo, and David Rabinowitz discovered Eris on January 5, 2005.
The Quadrantid meteor shower is predicted to peak around 9:00 p.m. EST on January 3rd. Unfortunately, the radiant, which lies at the junction of the constellations of Boötes, Hercules, and Draco, in what was once called Quadrans Muralis, will be below the horizon at that time. However, a waning crescent Moon will not compromise this year’s Quadrantids. The Quadrantid shower can sometimes reach zenithal hourly rates of more than 100 meteors per hour for a relatively short period of time. The near-Earth asteroid 2003 EH1, which may be an extinct comet, is believed to be the source of these meteors. See pages 48 and 49 of the January 2019 issue of Sky & Telescope or browse earthsky.org/?p=155137 and amsmeteors.org/2018/12/viewing-the-2019-quadrantid-meteor-shower/ for more on the Quadrantids.
Information on Iridium flares and passes of the ISS, the Tiangong-2, the X-37B, the HST, and other satellites can be found at www.heavens-above.com/ and www.calsky.com/cs.cgi/Satellites?obs=42301117054103
The Moon is 24.5 days old, is illuminated 25.0%, subtends 30.4 arc minutes, and is located in Libra on January 1st at 0:00 UT. The Moon is at apogee (distance 63.67 Earth-radii) on January 9th and is at perigee (distance 56.03 Earth-radii) on January 21st. New Moon occurs on January 6th. A so-called supermoon, the first of three for 2019, occurs on January 21st. A supermoon is more accurately described as a perigee syzygy of the Earth-Moon-Sun system or more simply as a perigean Full Moon. A total lunar eclipse, the 27th of Saros 134, takes place throughout most of North America, South America, the eastern Pacific Ocean, the western Atlantic Ocean, extreme western Europe, and extreme western Africa on January 21st. The Moon is located in Gemini during this event. The first penumbral contact occurs at 2:36 UT and the fourth at 7:48 UT. The partial phase begins at 3:34 UT and ends at 6:51 UT. Totality starts at 7:41 UT and ends at 7:44 UT. The instant of greatest eclipse takes place at 5:12 UT. The bright open cluster M44 lies some seven degrees to the east of the Moon during the eclipse. For more on this event, browse eclipse.gsfc.nasa.gov/LEplot/LEplot2001/LE2019Jan21T.pdf and www.eclipsewise.com/lunar/LEprime/2001-2100/LE2019Jan21Tprime.html or see pages 18-21 of the January 2019 issue of Sky & Telescope and page 36 of the January 2019 issue of Astronomy. The Moon occults Venus on January 31st from western South America and Polynesia. See www.lunar-occultations.com/iota/planets/0131venus.htm for further information. Click on www.lunar-occultations.com/iota/iotandx.htm for information on other lunar occultation events. 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 crater 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. It enters Capricornus on January 20th. A partial solar eclipse, the 58th of Saros 102, will be visible from parts of northeastern Asia and the northern Pacific Ocean on January 6th. For more on this eclipse, see eclipse.gsfc.nasa.gov/SEplot/SEplot2001/SE2019Jan06P.GIF and www.eclipsewise.com/solar/SEprime/2001-2100/SE2019Jan06Pprime.html
Data (magnitude, apparent size, illumination, and distance from the Earth in astronomical units) for the planets and Pluto on January 1st: Mercury (-0.4, 5.2", 89%, 1.30 a.u., Ophiuchus), Venus (-4.6, 26.3", 47%, 0.64 a.u., Libra), Mars (+0.5, 7.4", 87%, 1.26 a.u., Pisces), Jupiter (-1.8, 31.8", 100%, 6.19 a.u., Ophiuchus), Saturn (+0.5, 15.0", 100%, 11.04 a.u., Sagittarius), Uranus (+5.8, 3.6", 100%, 19.78 a.u. on January 16th, Pisces), Neptune (+7.9, 2.2", 100%, 30.58 a.u. on January 16th, Aquarius), Pluto (+14.3, 0.1", 100%, 34.70 a.u. on January 16th, Sagittarius).
During the evening, Mars and Neptune lie in the southwest and Uranus lies in the south. At midnight, Uranus is in the west. Mercury, Venus, Jupiter, and Saturn can be seen in the southeast in the morning.
On New Year’s Day, three bright planets (Mercury, Venus, and Jupiter) and a waning crescent Moon will form a 35-degree-long span across the southeast at dawn.
Mercury brightens this month but after January 4th grows too low to be seen as it heads sunward. A waning crescent Moon passes three degrees north of the planet on that date. Mercury reaches superior conjunction on January 30th.
Venus rises more than 3.5 hours before sunrise on New Year’s Day for observers at 40 degrees north. The waning crescent Moon passes within five degrees of the planet that morning. Venus reaches maximum western elongation on January 6th. Venus, Jupiter, and Antares form a rough right triangle on January 19th. On January 22nd, Venus and Jupiter lie within 2.4 degrees of each other. Antares is located just a bit more than eight degrees from the pair. The two brightest planets are separated by a bit more than four degrees on January 26th. By the end of the month, that gap increases to over nine degrees. On the morning of January 31st, the waning crescent Moon lies between Venus and Jupiter and is situated about two degrees from Venus. During January, Venus decreases in apparent diameter from 26.3 arc seconds to 19.4 arc seconds but increases in illumination from 47% to 62%.
Earth is 0.9833 a.u. distant from the Sun at perihelion on January 3rd. On that date, it’s 3% (5.0 million kilometers or 3.1 million miles) closer to the Sun than at aphelion on July 6th and about 2.7% closer to the Sun than on average.
Mars fades from magnitude +0.5 to magnitude +0.9 this month and shrinks to an apparent diameter of 6.2 arc seconds. A waxing crescent Moon passes five degrees south-southeast of Mars on the night of January 12th/13th. The Red Planet sets by 11:00 p.m. local time
Jupiter’s disk increases in apparent size from 31.8 arc seconds to 33.6 arc seconds as the planet brightens slightly from magnitude -1.8 to magnitude -1.9 during January. A slender waning crescent Moon lies about three degrees from Jupiter on the morning of January 3rd and about six degrees from the planet on January 30th. 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 51 of the January 2019 issue of Sky & Telescope. Click on www.skyandtelescope.com/observing/interactive-sky-watching-tools/ or consult page 50 of the January 2019 issue of Sky & Telescope to determine transit times of the central meridian by the Great Red Spot.
Saturn is in conjunction with the Sun on January 2nd and is not visible again until the second half of the month. The Ringed Planet attains an altitude of approximately seven degrees in the southeast about 45 minutes before sunrise on January 31st.
Uranus is located in extreme eastern Pisces. It’s situated 1.2 degrees north of the fourth-magnitude star Omicron Piscium during the first half of the month. By January 31st, Uranus has moved to a position 1.4 degrees north-northeast of the star. Uranus is stationary on January 7th and is at eastern quadrature on January 19th. The First Quarter Moon passes five degrees south-southeast of Uranus on January 14th. The seventh planet sets after midnight.
As twilight ends in early January, Neptune lies about 30 degrees above the southwestern horizon. The eighth planet can be found halfway between the fourth-magnitude stars Lambda and Phi Aquarii. On January 1st, it is located 14 arc minutes southeast of the sixth-magnitude star 81 Aquarii. By the end of the month, Neptune lies 55 arc minutes east of that star and 46 arc minutes north of the fifth-magnitude star 83 Aquarii. The waxing crescent Moon passes three degrees south of Neptune on January 10th.
Online finder charts for Uranus and Neptune can be found at www.nakedeyeplanets.com/uranus.htm and www.nakedeyeplanets.com/neptune.htm and also at www.skyandtelescope.com/wp-content/uploads/WEB_UrNep18.pdf and on pages 48 and 49 of the September 2018 issue of Sky & Telescope.
See www.curtrenz.com/uranep.html for additional information on the two outer planets.
Click on www.skyandtelescope.com/observing/interactive-sky-watching-tools/ for JavaScript utilities that will illustrate the positions of the five brightest satellites of Uranus and the position of Triton, Neptune’s brightest satellite.
The dwarf planet Pluto is in conjunction with the Sun on January 11th.
For more on the planets and how to locate them, browse www.nakedeyeplanets.com/
Asteroid 433 Eros heads southeastward along the Perseus-Auriga border this month, eventually entering Taurus as January ends. It comes closest to the Earth on January 15th. On that date, 433 Eros will be approximately 19,000,000 miles from the Earth and will shine at ninth magnitude, the brightest it will be until 2056. 433 Eros will be moving almost one degree per day so a noticeable change in its position should be noticeable in 30 minutes time at a magnification of 100x. Asteroids brighter than magnitude +11.0 that reach opposition this month include 216 Kleopatra (magnitude +10.6) on January 10th, 704 Interamnia (magnitude +10.3) on January 15th, and 324 Bamberga (magnitude +10.4) on January 21st. See asteroidoccultation.com/2019_01_si.htm for information on asteroid occultation events taking place this month. Consult www.curtrenz.com/asteroids.html to learn more about a number of asteroids.
Comet 46P/Wirtanen glides northeastward through Lynx and Ursa Major during January. On January 10th, the brightest periodic comet of last year passes one degree south of the third magnitude star Ursae Majoris. As the comet departs the inner solar system, its brightness may drop to ninth magnitude. The recently discovered Comet C/2018 Y1 (Iwamoto) will reach perihelion in Leo in early February and may brighten to seventh or eighth magnitude. During January, it travels northwestward through northeastern Hydra and southern Virgo. Browse www.britastro.org/sites/default/files/2018y1.pdf for a finder chart and earthsky.org/astronomy-essentials/c-2018-y1-iwamoto-jan-feb-2019 for an article on the comet. Visit cometchasing.skyhound.com/ and www.aerith.net/comet/future-n.html for information on these and other comets visible this month.
A wealth of information on solar system celestial bodies is posted at www.curtrenz.com/astronomy.html and nineplanets.org/
The major meteor showers that will occur this year are discussed at www.skyandtelescope.com/observing/best-meteor-showers-in-2019/
Various events taking place within our solar system are discussed at www.bluewaterastronomy.info/styled-4/index.html
Information on the celestial events transpiring each week can be found at astronomy.com/skythisweek and www.skyandtelescope.com/observing/sky-at-a-glance/
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 six inches.
The famous eclipsing variable star Algol (Beta Persei) is at a minimum, decreasing in magnitude from 2.1 to 3.4, on January 3rd, 6th, 9th, 12th, 15th, 17th, 20th, 23rd, 26th, and 29th. The Demon Star is at minimum brightness for approximately two hours and is well-placed for observers in North America on the night of January 11th/12th, centered at 1:21 a.m. EST. Minima can also be observed on the night of January 14th/15th, centered at 10:10 p.m. EST, and on the evening of January 17th, centered at 6:59 p.m. EST. Consult page 50 of the January 2019 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
Data on current supernovae can be found at www.rochesterastronomy.org/snimages/
Information on observing some of the more prominent Messier galaxies is available at www.cloudynights.com/topic/358295-how-to-locate-some-of-the-major-messier-galaxies-and-helpful-advice-for-novice-amateur-astronomers/
Finder charts for the Messier objects and other deep-sky objects are posted at freestarcharts.com/messier and freestarcharts.com/ngc-ic and www.cambridge.org/turnleft/seasonal_skies_january-march
Telrad finder charts for the Messier Catalog and the SAC’s 110 Best of the NGC are posted at www.astro-tom.com/messier/messier_finder_charts/messier_maps.htm and sao64.free.fr/observations/catalogues/cataloguesac.pdf
Deep-sky object list generators can be found at dso-browser.com/ and www.virtualcolony.com/sac/ and tonightssky.com/MainPage.php
Free sky atlases can be downloaded at www.deepskywatch.com/files/deepsky-atlas/Deep-Sky-Hunter-atlas-full.pdf and www.cloudynights.com/articles/cat/articles/observing-skills/free-mag-7-star-charts-r1021 and allans-stuff.com/triatlas/
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)
1/1 The Moon is 1.3 degrees north of Venus at 22:00
1/2 Mercury is at the descending node through the ecliptic plane at 0:00; Mars crosses north of the celestial equator at 1:00; Saturn is in conjunction with the Sun at 6:00
1/3 The Moon is 8.4 degrees north-northeast of first-magnitude star Antares (Alpha Scorpii) at 5:00; the Earth is at perihelion (147,099,761 kilometers or 91,403,554 miles distant from the Sun) at 5:20; the Moon is 3.1 degrees north-northeast of Jupiter at 10:00
1/4 The latest sunrise of 2019 at latitude 40 degrees north occurs today; the peak of the Quadrantid meteor shower (40 to 120 or more per hour) is predicted to occur at 2:30; the Moon is 2.8 degrees north of Mercury at 19:00
1/5 The Moon is 0.9 degree north of Saturn at 19:00; Venus is at dichotomy (50% illuminated) at 19:00; a partial solar eclipse visible from China, Korea, Japan, Russia, the northern Pacific Ocean, and the Aleutian Islands begins at 23:34
1/6 New Moon (lunation 1188) occurs at 1:28; the instant of greatest eclipse for the ongoing partial solar eclipse takes place at 01:41; the partial solar eclipse ends at 3:48; Venus is at greatest western elongation (46.9 degrees) at 5:00; Uranus is stationary in longitude at 18:00
1/7 Uranus is stationary in right ascension, with direct motion to resume, at 0:00; the Moon is at descending node (longitude 296.7 degrees) at 0:08; the Moon displays minimum libration for the year (1.2 degrees) at 15:00
1/8 The latest onset of morning twilight of 2019 at latitude 40 degrees north occurs today
1/9 The Moon is at apogee, subtending 29' 25" from a distance of 406,117 kilometers (252,850 miles), at 4:00
1/10 Mercury is at its southernmost declination (-24.1 degrees) at 18:00; the Moon is 3.0 degrees south of Neptune at 22:00
1/11 Pluto is in conjunction with the Sun at 12:00
1/12 Mercury is at aphelion (0.4667 a.u. from the Sun) at 8:00
1/13 The Moon is 5.0 degrees south-southeast of Mars at 1:00; Mercury (magnitude -0.6) is 1.7 degrees south of Saturn (magnitude +0.5) at 12:00; 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 be fully formed at approximately 12:35
1/14 First Quarter Moon occurs at 6:46; the Moon is 4.8 degrees south-southeast of Uranus at 17:00
1/15 Mars is at the ascending node through the ecliptic plane at 5:00
1/16 Venus (magnitude -4.4) is 7.8 degrees north of the first-magnitude star Antares at 23:00
1/17 The Moon is 8.5 degrees south-southeast of the bright open cluster M45 (the Pleiades or Subaru) in Taurus at 3:00; the middle of the eclipse season (the Sun is at same longitude as the descending node of the Moon, 296.7 degrees) occurs at 8:00; Venus is at its northernmost latitude from the ecliptic plane (3.4 degrees) at 8:00; the Moon is 1.6 degrees north of the first magnitude star Aldebaran (Alpha Tauri) at 19:00
1/18 Mercury (magnitude -0.8) is 1.5 degrees south of Pluto (magnitude +14.3) at 20:00
1/19 Uranus is at eastern quadrature (90 degrees from the Sun) at 1:00
1/20 The Sun enters Capricornus (ecliptic longitude 299.7 degrees) at 2:00; the Moon is 7.0 degrees south of the first-magnitude star Pollux (Beta Geminorum) at 19:00; the Moon is at the ascending node (longitude 116.8 degrees) at 22:48
1/21 A partial lunar eclipse begins at 3:34; the instant of greatest eclipse occurs at 5:12; Full Moon (known as the Ice Moon, the Moon after Yule, the Old Moon, and the Wolf Moon) occurs at 5:16; the partial lunar eclipse ends at 6:51; the Moon is 0.6 degree south of the bright open cluster M44 (the Beehive Cluster or Praesepe) in Cancer at 15:32; the Moon is at perigee (just 14.7 hours after Full Moon), subtending 33' 26" from a distance of 357,342 kilometers (222,042 miles), at 20:00
1/22 Venus (magnitude -4.3) is 2.4 degrees north of Jupiter (magnitude -1.8) at 16:00
1/23 The Moon is 2.5 degrees north-northeast of the first-magnitude star Regulus (Alpha Leonis) at 4:00
1/26 The Moon is 7.3 degrees north-northeast of the first-magnitude star Spica (Alpha Virginis), at 21:00
1/27 The Moon displays maximum libration for the year (10.1 degrees) at 17:00; Last Quarter Moon occurs at 21:10
1/29 The Curtiss Cross, an X-shaped clair-obscure illumination effect located between the craters Parry and Gambart, is predicted to be fully formed at 15:54
1/30 Mercury is at superior conjunction with the Sun (latitude -6.9 degrees) at 3:00; the Moon is 8.4 degrees north-northeast of Antares at 11:00
1/31 The Moon is 2.7 degrees north-northeast of Jupiter at 2:00; the Moon is 0.1 degree east-northeast of Venus, with an occultation occurring in western South America and Polynesia, at 18:00
Johannes Hevelius (1611-1687), Ernst Abbe (1840-1905), George Van Biesbroeck (1880-1974), Luboš Kohoutek (1935), and Stephen Hawking (1942) were born this month.
Galileo Galilei discovered Io, Europa, and Callisto on January 7, 1610. Galileo Galilei discovered Ganymede on January 13, 1610. Nicolas-Louis de Lacaille discovered the emission nebula NGC 3372 (the Eta Carinae Nebula) on January 25, 1752. Charles Messier discovered the globular cluster M56 on January 23, 1779. Charles Messier discovered the globular cluster M80 on January 4, 1781. William Herschel discovered the spiral galaxy NGC 1084 on January 10, 1785. Pierre François André Méchain discovered Comet 2P/Encke on January 17, 1786. 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. Louis Daguerre took the first photograph of the Moon on January 2, 1839. Alvan Clark discovered the white dwarf star Sirius B (the Pup) on January 31, 1862. The 36-inch Clark refractor at the Lick Observatory saw first light on January 3, 1888. Charles Perrine discovered the Jovian satellite Elara on January 2, 1905. Philibert Jacques Melotte discovered the Jovian satellite Pasiphae on January 27, 1908. Clyde Tombaugh photographed Pluto on January 23, 1930. Mike Brown, Chad Trujillo, and David Rabinowitz discovered Eris on January 5, 2005.
The Quadrantid meteor shower is predicted to peak around 9:00 p.m. EST on January 3rd. Unfortunately, the radiant, which lies at the junction of the constellations of Boötes, Hercules, and Draco, in what was once called Quadrans Muralis, will be below the horizon at that time. However, a waning crescent Moon will not compromise this year’s Quadrantids. The Quadrantid shower can sometimes reach zenithal hourly rates of more than 100 meteors per hour for a relatively short period of time. The near-Earth asteroid 2003 EH1, which may be an extinct comet, is believed to be the source of these meteors. See pages 48 and 49 of the January 2019 issue of Sky & Telescope or browse earthsky.org/?p=155137 and amsmeteors.org/2018/12/viewing-the-2019-quadrantid-meteor-shower/ for more on the Quadrantids.
Information on Iridium flares and passes of the ISS, the Tiangong-2, the X-37B, the HST, and other satellites can be found at www.heavens-above.com/ and www.calsky.com/cs.cgi/Satellites?obs=42301117054103
The Moon is 24.5 days old, is illuminated 25.0%, subtends 30.4 arc minutes, and is located in Libra on January 1st at 0:00 UT. The Moon is at apogee (distance 63.67 Earth-radii) on January 9th and is at perigee (distance 56.03 Earth-radii) on January 21st. New Moon occurs on January 6th. A so-called supermoon, the first of three for 2019, occurs on January 21st. A supermoon is more accurately described as a perigee syzygy of the Earth-Moon-Sun system or more simply as a perigean Full Moon. A total lunar eclipse, the 27th of Saros 134, takes place throughout most of North America, South America, the eastern Pacific Ocean, the western Atlantic Ocean, extreme western Europe, and extreme western Africa on January 21st. The Moon is located in Gemini during this event. The first penumbral contact occurs at 2:36 UT and the fourth at 7:48 UT. The partial phase begins at 3:34 UT and ends at 6:51 UT. Totality starts at 7:41 UT and ends at 7:44 UT. The instant of greatest eclipse takes place at 5:12 UT. The bright open cluster M44 lies some seven degrees to the east of the Moon during the eclipse. For more on this event, browse eclipse.gsfc.nasa.gov/LEplot/LEplot2001/LE2019Jan21T.pdf and www.eclipsewise.com/lunar/LEprime/2001-2100/LE2019Jan21Tprime.html or see pages 18-21 of the January 2019 issue of Sky & Telescope and page 36 of the January 2019 issue of Astronomy. The Moon occults Venus on January 31st from western South America and Polynesia. See www.lunar-occultations.com/iota/planets/0131venus.htm for further information. Click on www.lunar-occultations.com/iota/iotandx.htm for information on other lunar occultation events. 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 crater 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. It enters Capricornus on January 20th. A partial solar eclipse, the 58th of Saros 102, will be visible from parts of northeastern Asia and the northern Pacific Ocean on January 6th. For more on this eclipse, see eclipse.gsfc.nasa.gov/SEplot/SEplot2001/SE2019Jan06P.GIF and www.eclipsewise.com/solar/SEprime/2001-2100/SE2019Jan06Pprime.html
Data (magnitude, apparent size, illumination, and distance from the Earth in astronomical units) for the planets and Pluto on January 1st: Mercury (-0.4, 5.2", 89%, 1.30 a.u., Ophiuchus), Venus (-4.6, 26.3", 47%, 0.64 a.u., Libra), Mars (+0.5, 7.4", 87%, 1.26 a.u., Pisces), Jupiter (-1.8, 31.8", 100%, 6.19 a.u., Ophiuchus), Saturn (+0.5, 15.0", 100%, 11.04 a.u., Sagittarius), Uranus (+5.8, 3.6", 100%, 19.78 a.u. on January 16th, Pisces), Neptune (+7.9, 2.2", 100%, 30.58 a.u. on January 16th, Aquarius), Pluto (+14.3, 0.1", 100%, 34.70 a.u. on January 16th, Sagittarius).
During the evening, Mars and Neptune lie in the southwest and Uranus lies in the south. At midnight, Uranus is in the west. Mercury, Venus, Jupiter, and Saturn can be seen in the southeast in the morning.
On New Year’s Day, three bright planets (Mercury, Venus, and Jupiter) and a waning crescent Moon will form a 35-degree-long span across the southeast at dawn.
Mercury brightens this month but after January 4th grows too low to be seen as it heads sunward. A waning crescent Moon passes three degrees north of the planet on that date. Mercury reaches superior conjunction on January 30th.
Venus rises more than 3.5 hours before sunrise on New Year’s Day for observers at 40 degrees north. The waning crescent Moon passes within five degrees of the planet that morning. Venus reaches maximum western elongation on January 6th. Venus, Jupiter, and Antares form a rough right triangle on January 19th. On January 22nd, Venus and Jupiter lie within 2.4 degrees of each other. Antares is located just a bit more than eight degrees from the pair. The two brightest planets are separated by a bit more than four degrees on January 26th. By the end of the month, that gap increases to over nine degrees. On the morning of January 31st, the waning crescent Moon lies between Venus and Jupiter and is situated about two degrees from Venus. During January, Venus decreases in apparent diameter from 26.3 arc seconds to 19.4 arc seconds but increases in illumination from 47% to 62%.
Earth is 0.9833 a.u. distant from the Sun at perihelion on January 3rd. On that date, it’s 3% (5.0 million kilometers or 3.1 million miles) closer to the Sun than at aphelion on July 6th and about 2.7% closer to the Sun than on average.
Mars fades from magnitude +0.5 to magnitude +0.9 this month and shrinks to an apparent diameter of 6.2 arc seconds. A waxing crescent Moon passes five degrees south-southeast of Mars on the night of January 12th/13th. The Red Planet sets by 11:00 p.m. local time
Jupiter’s disk increases in apparent size from 31.8 arc seconds to 33.6 arc seconds as the planet brightens slightly from magnitude -1.8 to magnitude -1.9 during January. A slender waning crescent Moon lies about three degrees from Jupiter on the morning of January 3rd and about six degrees from the planet on January 30th. 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 51 of the January 2019 issue of Sky & Telescope. Click on www.skyandtelescope.com/observing/interactive-sky-watching-tools/ or consult page 50 of the January 2019 issue of Sky & Telescope to determine transit times of the central meridian by the Great Red Spot.
Saturn is in conjunction with the Sun on January 2nd and is not visible again until the second half of the month. The Ringed Planet attains an altitude of approximately seven degrees in the southeast about 45 minutes before sunrise on January 31st.
Uranus is located in extreme eastern Pisces. It’s situated 1.2 degrees north of the fourth-magnitude star Omicron Piscium during the first half of the month. By January 31st, Uranus has moved to a position 1.4 degrees north-northeast of the star. Uranus is stationary on January 7th and is at eastern quadrature on January 19th. The First Quarter Moon passes five degrees south-southeast of Uranus on January 14th. The seventh planet sets after midnight.
As twilight ends in early January, Neptune lies about 30 degrees above the southwestern horizon. The eighth planet can be found halfway between the fourth-magnitude stars Lambda and Phi Aquarii. On January 1st, it is located 14 arc minutes southeast of the sixth-magnitude star 81 Aquarii. By the end of the month, Neptune lies 55 arc minutes east of that star and 46 arc minutes north of the fifth-magnitude star 83 Aquarii. The waxing crescent Moon passes three degrees south of Neptune on January 10th.
Online finder charts for Uranus and Neptune can be found at www.nakedeyeplanets.com/uranus.htm and www.nakedeyeplanets.com/neptune.htm and also at www.skyandtelescope.com/wp-content/uploads/WEB_UrNep18.pdf and on pages 48 and 49 of the September 2018 issue of Sky & Telescope.
See www.curtrenz.com/uranep.html for additional information on the two outer planets.
Click on www.skyandtelescope.com/observing/interactive-sky-watching-tools/ for JavaScript utilities that will illustrate the positions of the five brightest satellites of Uranus and the position of Triton, Neptune’s brightest satellite.
The dwarf planet Pluto is in conjunction with the Sun on January 11th.
For more on the planets and how to locate them, browse www.nakedeyeplanets.com/
Asteroid 433 Eros heads southeastward along the Perseus-Auriga border this month, eventually entering Taurus as January ends. It comes closest to the Earth on January 15th. On that date, 433 Eros will be approximately 19,000,000 miles from the Earth and will shine at ninth magnitude, the brightest it will be until 2056. 433 Eros will be moving almost one degree per day so a noticeable change in its position should be noticeable in 30 minutes time at a magnification of 100x. Asteroids brighter than magnitude +11.0 that reach opposition this month include 216 Kleopatra (magnitude +10.6) on January 10th, 704 Interamnia (magnitude +10.3) on January 15th, and 324 Bamberga (magnitude +10.4) on January 21st. See asteroidoccultation.com/2019_01_si.htm for information on asteroid occultation events taking place this month. Consult www.curtrenz.com/asteroids.html to learn more about a number of asteroids.
Comet 46P/Wirtanen glides northeastward through Lynx and Ursa Major during January. On January 10th, the brightest periodic comet of last year passes one degree south of the third magnitude star Ursae Majoris. As the comet departs the inner solar system, its brightness may drop to ninth magnitude. The recently discovered Comet C/2018 Y1 (Iwamoto) will reach perihelion in Leo in early February and may brighten to seventh or eighth magnitude. During January, it travels northwestward through northeastern Hydra and southern Virgo. Browse www.britastro.org/sites/default/files/2018y1.pdf for a finder chart and earthsky.org/astronomy-essentials/c-2018-y1-iwamoto-jan-feb-2019 for an article on the comet. Visit cometchasing.skyhound.com/ and www.aerith.net/comet/future-n.html for information on these and other comets visible this month.
A wealth of information on solar system celestial bodies is posted at www.curtrenz.com/astronomy.html and nineplanets.org/
The major meteor showers that will occur this year are discussed at www.skyandtelescope.com/observing/best-meteor-showers-in-2019/
Various events taking place within our solar system are discussed at www.bluewaterastronomy.info/styled-4/index.html
Information on the celestial events transpiring each week can be found at astronomy.com/skythisweek and www.skyandtelescope.com/observing/sky-at-a-glance/
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 six inches.
The famous eclipsing variable star Algol (Beta Persei) is at a minimum, decreasing in magnitude from 2.1 to 3.4, on January 3rd, 6th, 9th, 12th, 15th, 17th, 20th, 23rd, 26th, and 29th. The Demon Star is at minimum brightness for approximately two hours and is well-placed for observers in North America on the night of January 11th/12th, centered at 1:21 a.m. EST. Minima can also be observed on the night of January 14th/15th, centered at 10:10 p.m. EST, and on the evening of January 17th, centered at 6:59 p.m. EST. Consult page 50 of the January 2019 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
Data on current supernovae can be found at www.rochesterastronomy.org/snimages/
Information on observing some of the more prominent Messier galaxies is available at www.cloudynights.com/topic/358295-how-to-locate-some-of-the-major-messier-galaxies-and-helpful-advice-for-novice-amateur-astronomers/
Finder charts for the Messier objects and other deep-sky objects are posted at freestarcharts.com/messier and freestarcharts.com/ngc-ic and www.cambridge.org/turnleft/seasonal_skies_january-march
Telrad finder charts for the Messier Catalog and the SAC’s 110 Best of the NGC are posted at www.astro-tom.com/messier/messier_finder_charts/messier_maps.htm and sao64.free.fr/observations/catalogues/cataloguesac.pdf
Deep-sky object list generators can be found at dso-browser.com/ and www.virtualcolony.com/sac/ and tonightssky.com/MainPage.php
Free sky atlases can be downloaded at www.deepskywatch.com/files/deepsky-atlas/Deep-Sky-Hunter-atlas-full.pdf and www.cloudynights.com/articles/cat/articles/observing-skills/free-mag-7-star-charts-r1021 and allans-stuff.com/triatlas/
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.