Post by Dave Mitsky on Jan 31, 2019 9:38:49 GMT
February Celestial Calendar by Dave Mitsky
All times, unless otherwise noted, are UT (subtract five hours and, when appropriate, one calendar day for EST)
2/1 Mercury is at its southernmost latitude from the ecliptic plane (-7.0 degrees) at 15:00
2/2 The Moon is 0.6 degree north of Saturn, with an occultation occurring in portions of southern Russia, western Asia, the Middle East, southern and central Europe, and northern and northeastern Africa, at 7:00; the Moon is 0.6 degree north of Pluto, with an occultation occurring in western and central North America (with the exception of Alaska), the Aleutian Islands, Hawaii, and northern Micronesia, at 20:00
2/3 The astronomical cross-quarter day (i.e., a day half way between a solstice and an equinox) known as Imbolc, Candlemas, or Groundhog Day occurs astronomically at 3:01; the Moon is at the descending node (longitude 296.8 degrees) at 7:00
2/4 New Moon (lunation 1189) occurs at 21:04
2/5 The Moon is 0.2 degree southeast of Mercury at 8:00; the Moon is at apogee, subtending 29' 23" from a distance of 406,555 kilometers (252,622 miles), at 9:29
2/6 Asteroid 532 Herculina (magnitude +8.9) is at opposition at 3:00; the Moon is 1.1 degrees north of asteroid 4 Vesta, with an occultation occurring in portions of western Russia, at 8:00
2/7 The Moon is 3.0 degrees south-southeast of Neptune at 9:00
2/10 The Moon, Mars, and Uranus lie within a circle with a diameter of 5.7 degrees at 20:00; the Moon is 5.7 degrees south-southeast of Mars at 22:00
2/11 The Moon is 4.7 degrees south-southeast of Uranus at 1:00; the equation of time is at a minimum for the year (-14.24 minutes) at 16:00
2/12 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 2:13; First Quarter Moon occurs at 22:26
2/13 Mars (magnitude +1.0) is 1.0 degree north-northwest of Uranus (magnitude +5.8) at 6:00; the Moon is 8.4 degrees south-southeast of the bright open cluster M45 (the Pleiades or Subaru) in Taurus at 11:00
2/14 The Moon is 1.7 degrees north of the first-magnitude star Aldebaran (Alpha Tauri) at 4:00
2/16 The Sun enters Aquarius (ecliptic longitude 327.9 degrees) at 21:00
2/17 The Moon is 7.0 degrees south of the first-magnitude star Pollux (Beta Geminorum) at 6:00; the Moon is at the ascending node (longitude 116.5 degrees) at 10:00
2/18 Venus (magnitude -4.1) is 1.1 degrees north of Saturn (magnitude +0.7) at 13:00; the Sun is at a longitude of 330 degrees at 23:00
2/19 Mercury (magnitude -1.0) is 0.7 degree north-northwest of Neptune (magnitude +8.0) at 6:00; the Moon is at perigee, subtending 33' 29" from a distance of 356,761 kilometers (221,681 miles), at 9:03; the Moon is 2.4 degrees north-northeast of the first-magnitude star Regulus (Alpha Leonis) at 15:00; Full Moon (known as the Hunger, Snow, or Storm Moon) occurs at 15:54
2/20 Mercury is at the ascending node through the ecliptic plane at 16:00
2/23 Venus, Saturn, and Pluto lie within a circle 5.1 degrees in diameter at 0:00; Venus (magnitude -4.1) is 1.4 degrees north of Pluto (magnitudes +14.3) at 6:00; the Moon is 7.2 degrees north-northeast of Spica at 6:00; Mars and Jupiter are at heliocentric opposition (longitudes 71.0 degrees and 251.0 degrees) at 11:00
2/25 Mercury is at perihelion (0.3075 astronomical units from the sun) at 8:00
2/26 Last Quarter Moon occurs at 11:28; the Moon is 8.3 degrees north-northeast of the first-magnitude star Antares (Alpha Scorpii) at 17:00
2/27 Mercury is at greatest eastern elongation (18.0 degrees) at 1:00; the Moon is 2.3 degrees north-northeast of Jupiter at 16:00
2/28 The Curtiss Cross, an X-shaped clair-obscure illumination effect located between the craters Parry and Gambart, is predicted to be visible at 6:06
Nicolas Copernicus (1473-1543), Galileo Galilei (1564-1642), Jacques Cassini (1677-1756), William Huggins (1824-1910), John Dreyer (1852-1926), Bernard Lyot (1897-1952), and Clyde Tombaugh (1906-1997) were born this month.
Nicolas Louis de Lacaille discovered the open cluster NGC 3228 in Vela on February 11, 1752. Nicolas Louis de Lacaille discovered the face-on barred spiral galaxy M83in Hydra on February 23, 1752. Johann Bode discovered the globular cluster M53 in Coma Berenices on February 3, 1775. The planetary nebula M97 in Ursa Major was discovered by Pierre François André Méchain on February 16, 1781. Caroline Herschel discovered the open cluster NGC 2360 in Canis Major on February 26, 1783. William Herschel discovered the face-on barred spiral galaxy NGC 4027 in Corvus on February 7, 1785. William Herschel’s 40-foot-focal-length telescope saw first light on February 19, 1787. Clyde Tombaugh discovered Pluto on February 18, 1930. James Hey detected radio waves emitted by the Sun on February 27, 1942. Gerald Kuiper discovered the Uranian satellite Miranda (magnitude +15.8) on February 16, 1948. The first pulsar, PSR B1919+21, was discovered by Jocelyn Bell Burnell and Antony Hewish on February 24, 1967. Supernova 1987A was discovered by Ian Shelton, Oscar Duhalde, and Albert Jones on February 23, 1987.
The zodiacal light should be visible from a dark location in the west after evening twilight for two weeks starting on February 21st. Click on www.atoptics.co.uk/highsky/zod1.htm for more on the zodiacal light.
Information on Iridium flares, which will soon be coming to an end, and passes of the ISS, the Tiangong-2, the USAF’s X-37B, the HST, and other satellites can be found at www.heavens-above.com/
The Moon is 25.7 days old, is illuminated 14.5%, subtends 29.5', and is located in the constellation of Sagittarius at 0:00 UT on February 1st. The Moon attains its greatest northern declination (+21.5 degrees) for the month on February 16th and greatest southern declination (-21.5 degrees) on February 2nd. Longitudinal libration is at a maximum of +7.7 degrees on February 25th and at a minimum of -7.7 degrees on February 12th. Latitudinal libration is at a maximum of +6.8 degrees on February 11th and a minimum of -6.7 degrees on December 23rd. New Moon occurs on February 4th. The Moon is at the farthest apogee of the year (distance 63.74 Earth-radii) on February 5th and at the nearest perigee of the year (distance 55.94 Earth-radii) on February 19th. Large tides will occur following the Full Moon on February 19th. On February 10th, the waxing crescent Moon, Mars, and Uranus lie within a circle with a diameter of less than six degrees. The waning crescent Moon lies almost halfway between Jupiter and Saturn, with Venus positioned to the lower left of the two gas giants, on the morning of February 28th. The Lunar X occurs on February 12th and the Curtiss Cross on February 28th. The Moon, from certain parts of the world, occults Saturn and Pluto on February 2nd and Vesta on February 6th. Browse www.lunar-occultations.com/iota/ for information on these events and upcoming lunar occultations. Click on www.calendar-12.com/moon_calendar/2019/february for a February 2019 lunar calendar. Visit saberdoesthestars.wordpress.com/2011/07/05/saber-does-the-stars/ for tips on spotting extreme crescent Moons. 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 the constellation of Capricornus on February 1st. It enters Aquarius on February 16th.
Brightness, apparent size, illumination, distance from the Earth in astronomical units, and location data for the planets and Pluto on February 1: Mercury (magnitude -1.5, 4.8", 100% illuminated, 1.40 a.u., Capricornus), Venus (magnitude -4.3, 19.2", 62% illuminated, 0.87 a.u., Sagittarius), Mars (magnitude +0.9, 6.1", 89% illuminated, 1.53 a.u., Pisces), Jupiter (magnitude -1.9, 33.6", 99% illuminated, 5.86 a.u., Ophiuchus), Saturn (magnitude +0.6, 15.2", 100% illuminated, 10.93 a.u., Sagittarius), Uranus (magnitude +5.8, 3.5", 100% illuminated, 20.28 a.u. on February 15th, Pisces), Neptune (magnitude +8.0, 2.2", 100% illuminated, 30.87 a.u. on February 15th, Aquarius), and Pluto (magnitude +14.3, 0.1", 100% illuminated, 34.30 a.u. on February 15th, Sagittarius).
Mercury can be seen in the west and Mars, Uranus, and Neptune in the southwest in the evening sky. In the morning sky, Venus, Jupiter, and Saturn lie in the southeast.
Mercury is at its greatest heliocentric latitude south on February 1st. It reappears from superior conjunction low in the west at dusk around February 11th or February 12th. Mercury is at the ascending node on February 20th and at perihelion on February 25th. The speediest planet reaches greatest eastern elongation on the North American evening of February 26th. Mercury is approximately nine degrees above the horizon 45 minutes after sunset at that time. This will be the best evening apparition of 2019 for northern hemisphere observers.
Venus is visible low in the southeast before sunrise. Observers in the southern hemisphere are favored. Venus decreases in apparent size from 19.2 arc seconds to 15.7 arc seconds and increases in illumination from 62% to 72% this month. It will remain in the gibbous phase for the rest of the year. The brightest planet passes two degrees north of M20 (the Trifid Nebula) on February 4th, two degrees south of the open cluster M25 and three degrees north of the globular cluster M22 on February 10th and February 11th, and just over one degree north of Saturn on February 18th. The planet’s eastward motion of about one degree per day places it less than three degrees north-northwest of the globular cluster M75 by the end of February.
Mars dims from magnitude +0.9 to magnitude +1.2 and shrinks in apparent diameter from 6.1 arc seconds to 5.3 arc seconds by the end of February. A crescent Moon passes six degrees southeast of Mars on February 10th. Mars departs Pisces and enters Aries on February 12th.
As February begins, Jupiter rises after 3:30 a.m. local time. By the end of February, the gas giant planet rises at 2:00 a.m. local time. It brightens from magnitude -1.9 to magnitude -2.0 and increases in apparent diameter from 33.6 arc seconds to 36.1 arc seconds this month. The waning crescent Moon passes two degrees to the north of Jupiter on February 27th. A shadow transit by the Galilean satellite Io takes place on the morning of February 6th starting at 10:45 UT (5:45 a.m. EST). Just over an hour later at 11:49 UT (6:49 a.m. EST), Io begins to transit the planet. Callisto lies due north of Jupiter that morning. 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 February 2019 issue of Sky & Telescope. Click on www.skyandtelescope.com/observing/interactive-sky-watching-tools/ or consult pages 50 and 51 of the February 2019 issue of Sky & Telescope to determine transit times of the central meridian by the Great Red Spot.
As the month ends, Saturn shines at magnitude +0.6. Its ring system spans 35 arc seconds and is inclined 24 degrees from edge-on. The waning crescent Moon passes less than one degree north of Saturn of February 2nd. Saturn and Venus lie within 2.5 degrees of each other from February 16th to February 20th. Saturn is 1.1 degrees south of Venus on February 18th. The Ringed Planet rises shortly after 4:00 a.m. local time by the end of February. For information on the satellites of Saturn, browse www.skyandtelescope.com/observing/interactive-sky-watching-tools/
Uranus enters Aries on February 5th, where it will remain for the remainder of the year. On February 1st, Uranus is located seven degrees east-northeast of Mars. The angular distance between the two planets decreases by more than one half degree per day. The gap narrows to 1.5 degrees by February 10th. On February 12th, Uranus is 1.0 degree south-southeast of Mars. The following day it is 1.1 degrees south of Mars.
Neptune lies 0.8 degree due north of the fifth-magnitude star 83 Aquarii on February 1st. The eighth planet moves to a position 0.9 degree northeast of 83 Aquarii a week later. Neptune disappears from view by the second week of February.
See curtrenz.com/uranep.html for additional information on the two outer planets.
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.
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 not visible this month.
For more on the planets and how to locate them, browse www.nakedeyeplanets.com/
Comet 46P/Wirtanen travels southeastward through Ursa Major during February. It passes less than one half of a degree west of the third-magnitude star Theta Ursa Majoris on February 10th and February 11th. Comet C/2018 Y1 (Iwamoto) will reach perihelion in early February. This speedy comet comes close to the spiral galaxy M104 (the Sombrero Galaxy) in Virgo on February 2nd and very close to the barred spiral galaxy M95 in Leo on February 10th. Comet Iwamoto will pass within 45 million kilometers (28 million miles) of the Earth on February 10th and reach a maximum predicted brightness of seventh magnitude. Click on earthsky.org/astronomy-essentials/c-2018-y1-iwamoto-jan-feb-2019 for more on this comet. Visit cometchasing.skyhound.com/ and www.aerith.net/comet/future-n.html for additional information on comets visible this month.
Asteroid 532 Herculina heads north-westward through Leo and Cancer this month. It reaches a peak magnitude of +8.9 when it reaches opposition on February 6th. Other asteroids brighter than magnitude +11.0 that reach opposition this month include 129 Antigone (magnitude +10.8) in Leo on February 17th and 349 Dembowska (magnitude +10.3) in Leo on February 27th. On the morning of February 11th, the sixteenth-magnitude asteroid 301 Bavaria occults the ninth-magnitude star HD 144893 (HIP 79094) in Scorpius for a maximum of 2.3 seconds for observers in parts of North America. Browse asteroidoccultation.com/2019_02/0211_301_62730.htm for more on this occultation. The seventeenth-magnitude asteroid 4388 occults the first-magnitude star Sirius (Alpha Canis Majoris) for a maximum of 1.8 seconds on the night of February 18th/19th from parts of North America. See asteroidoccultation.com/2019_02/0219_4388_62950.htm for additional information on this event and asteroidoccultation.com/2019_02_si.htm for information on other asteroid occultation events taking place this month. Consult www.curtrenz.com/asteroids.html to learn more about a number of asteroids
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 the month can be downloaded at www.skymaps.com/downloads.html and www.telescope.com/content.jsp?pageName=Monthly-Star-Chart
The famous eclipsing variable star Algol (Beta Persei) is at a minimum, decreasing in magnitude from 2.1 to 3.4, on February 1st, 4th, 7th, 9th, 12th, 15th, 18th, 21st, 24th, and 27th. Consult page 50 of the February 2019 issue of Sky & Telescope for the times of the minima. The Demon Star is at minimum brightness for approximately two hours centered at 11:55 p.m. EST on February 3rd (4:55 UT on February 4th), at 8:45 p.m. EST on February 6th (1:45 UT on February 7th), at 1:41 a.m. EST on February 24th (6:41 UT on February 24th), and at 10:30 p.m. EST on February 26th (3:30 UT on February 27th). 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/
Forty binary and multiple stars for February: 41 Aurigae, Struve 872, Otto Struve 147, Struve 929, 56 Aurigae (Auriga); Nu-1 Canis Majoris, 17 Canis Majoris, Pi Canis Majoris, Mu Canis Majoris, h3945, Tau Canis Majoris (Canis Major); Struve 1095, Struve 1103, Struve 1149, 14 Canis Minoris (Canis Minor); 20 Geminorum, 38 Geminorum, Alpha Geminorum (Castor), 15 Geminorum, Lambda Geminorum, Delta Geminorum, Struve 1108, Kappa Geminorum (Gemini); 5 Lyncis, 12 Lyncis, 19 Lyncis, Struve 968, Struve 1025 (Lynx); Epsilon Monocerotis, Beta Monocerotis, 15 (S) Monocerotis (Monoceros); Struve 855 (Orion); Struve 1104, k Puppis, 5 Puppis (Puppis)
Notable carbon star for February: BL Orionis (Orion)
Fifty deep-sky objects for February: NGC 2146, NGC 2403 (Camelopardalis); M41, NGC 2345, NGC 2359, NGC 2360, NGC 2362, NGC 2367, NGC 2383 (Canis Major); M35, NGC 2129, NGC 2158, NGC 2266, NGC 2355, NGC 2371-72, NGC 2392, NGC 2420 (Gemini); NGC 2419 (Lynx); M50, NGC 2232, NGC 2237, NGC 2238, NGC 2244, NGC 2245, NGC 2251, NGC 2261, NGC 2264, NGC 2286, NGC 2301, NGC 2311, NGC 2324, NGC 2335, NGC 2345, NGC 2346, NGC 2353 (Monoceros); NGC 2169, NGC 2174, NGC 2194 (Orion); M46, M47, M93, Mel 71, NGC 2421, NGC 2423, NGC 2438, NGC 2439, NGC 2440, NGC 2467, NGC 2506, NGC 2509 (Puppis)
Top ten binocular deep-sky objects for February: M35, M41, M46, M47, M50, M93, NGC 2244, NGC 2264, NGC 2301, NGC 2360
Top ten deep-sky objects for February: M35, M41, M46, M47, M50, M93, NGC 2261, NGC 2362, NGC 2392, NGC 2403
Challenge deep-sky object for February: IC 443 (Gemini)
The objects listed above are located between 6:00 and 8:00 hours of right ascension.
All times, unless otherwise noted, are UT (subtract five hours and, when appropriate, one calendar day for EST)
2/1 Mercury is at its southernmost latitude from the ecliptic plane (-7.0 degrees) at 15:00
2/2 The Moon is 0.6 degree north of Saturn, with an occultation occurring in portions of southern Russia, western Asia, the Middle East, southern and central Europe, and northern and northeastern Africa, at 7:00; the Moon is 0.6 degree north of Pluto, with an occultation occurring in western and central North America (with the exception of Alaska), the Aleutian Islands, Hawaii, and northern Micronesia, at 20:00
2/3 The astronomical cross-quarter day (i.e., a day half way between a solstice and an equinox) known as Imbolc, Candlemas, or Groundhog Day occurs astronomically at 3:01; the Moon is at the descending node (longitude 296.8 degrees) at 7:00
2/4 New Moon (lunation 1189) occurs at 21:04
2/5 The Moon is 0.2 degree southeast of Mercury at 8:00; the Moon is at apogee, subtending 29' 23" from a distance of 406,555 kilometers (252,622 miles), at 9:29
2/6 Asteroid 532 Herculina (magnitude +8.9) is at opposition at 3:00; the Moon is 1.1 degrees north of asteroid 4 Vesta, with an occultation occurring in portions of western Russia, at 8:00
2/7 The Moon is 3.0 degrees south-southeast of Neptune at 9:00
2/10 The Moon, Mars, and Uranus lie within a circle with a diameter of 5.7 degrees at 20:00; the Moon is 5.7 degrees south-southeast of Mars at 22:00
2/11 The Moon is 4.7 degrees south-southeast of Uranus at 1:00; the equation of time is at a minimum for the year (-14.24 minutes) at 16:00
2/12 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 2:13; First Quarter Moon occurs at 22:26
2/13 Mars (magnitude +1.0) is 1.0 degree north-northwest of Uranus (magnitude +5.8) at 6:00; the Moon is 8.4 degrees south-southeast of the bright open cluster M45 (the Pleiades or Subaru) in Taurus at 11:00
2/14 The Moon is 1.7 degrees north of the first-magnitude star Aldebaran (Alpha Tauri) at 4:00
2/16 The Sun enters Aquarius (ecliptic longitude 327.9 degrees) at 21:00
2/17 The Moon is 7.0 degrees south of the first-magnitude star Pollux (Beta Geminorum) at 6:00; the Moon is at the ascending node (longitude 116.5 degrees) at 10:00
2/18 Venus (magnitude -4.1) is 1.1 degrees north of Saturn (magnitude +0.7) at 13:00; the Sun is at a longitude of 330 degrees at 23:00
2/19 Mercury (magnitude -1.0) is 0.7 degree north-northwest of Neptune (magnitude +8.0) at 6:00; the Moon is at perigee, subtending 33' 29" from a distance of 356,761 kilometers (221,681 miles), at 9:03; the Moon is 2.4 degrees north-northeast of the first-magnitude star Regulus (Alpha Leonis) at 15:00; Full Moon (known as the Hunger, Snow, or Storm Moon) occurs at 15:54
2/20 Mercury is at the ascending node through the ecliptic plane at 16:00
2/23 Venus, Saturn, and Pluto lie within a circle 5.1 degrees in diameter at 0:00; Venus (magnitude -4.1) is 1.4 degrees north of Pluto (magnitudes +14.3) at 6:00; the Moon is 7.2 degrees north-northeast of Spica at 6:00; Mars and Jupiter are at heliocentric opposition (longitudes 71.0 degrees and 251.0 degrees) at 11:00
2/25 Mercury is at perihelion (0.3075 astronomical units from the sun) at 8:00
2/26 Last Quarter Moon occurs at 11:28; the Moon is 8.3 degrees north-northeast of the first-magnitude star Antares (Alpha Scorpii) at 17:00
2/27 Mercury is at greatest eastern elongation (18.0 degrees) at 1:00; the Moon is 2.3 degrees north-northeast of Jupiter at 16:00
2/28 The Curtiss Cross, an X-shaped clair-obscure illumination effect located between the craters Parry and Gambart, is predicted to be visible at 6:06
Nicolas Copernicus (1473-1543), Galileo Galilei (1564-1642), Jacques Cassini (1677-1756), William Huggins (1824-1910), John Dreyer (1852-1926), Bernard Lyot (1897-1952), and Clyde Tombaugh (1906-1997) were born this month.
Nicolas Louis de Lacaille discovered the open cluster NGC 3228 in Vela on February 11, 1752. Nicolas Louis de Lacaille discovered the face-on barred spiral galaxy M83in Hydra on February 23, 1752. Johann Bode discovered the globular cluster M53 in Coma Berenices on February 3, 1775. The planetary nebula M97 in Ursa Major was discovered by Pierre François André Méchain on February 16, 1781. Caroline Herschel discovered the open cluster NGC 2360 in Canis Major on February 26, 1783. William Herschel discovered the face-on barred spiral galaxy NGC 4027 in Corvus on February 7, 1785. William Herschel’s 40-foot-focal-length telescope saw first light on February 19, 1787. Clyde Tombaugh discovered Pluto on February 18, 1930. James Hey detected radio waves emitted by the Sun on February 27, 1942. Gerald Kuiper discovered the Uranian satellite Miranda (magnitude +15.8) on February 16, 1948. The first pulsar, PSR B1919+21, was discovered by Jocelyn Bell Burnell and Antony Hewish on February 24, 1967. Supernova 1987A was discovered by Ian Shelton, Oscar Duhalde, and Albert Jones on February 23, 1987.
The zodiacal light should be visible from a dark location in the west after evening twilight for two weeks starting on February 21st. Click on www.atoptics.co.uk/highsky/zod1.htm for more on the zodiacal light.
Information on Iridium flares, which will soon be coming to an end, and passes of the ISS, the Tiangong-2, the USAF’s X-37B, the HST, and other satellites can be found at www.heavens-above.com/
The Moon is 25.7 days old, is illuminated 14.5%, subtends 29.5', and is located in the constellation of Sagittarius at 0:00 UT on February 1st. The Moon attains its greatest northern declination (+21.5 degrees) for the month on February 16th and greatest southern declination (-21.5 degrees) on February 2nd. Longitudinal libration is at a maximum of +7.7 degrees on February 25th and at a minimum of -7.7 degrees on February 12th. Latitudinal libration is at a maximum of +6.8 degrees on February 11th and a minimum of -6.7 degrees on December 23rd. New Moon occurs on February 4th. The Moon is at the farthest apogee of the year (distance 63.74 Earth-radii) on February 5th and at the nearest perigee of the year (distance 55.94 Earth-radii) on February 19th. Large tides will occur following the Full Moon on February 19th. On February 10th, the waxing crescent Moon, Mars, and Uranus lie within a circle with a diameter of less than six degrees. The waning crescent Moon lies almost halfway between Jupiter and Saturn, with Venus positioned to the lower left of the two gas giants, on the morning of February 28th. The Lunar X occurs on February 12th and the Curtiss Cross on February 28th. The Moon, from certain parts of the world, occults Saturn and Pluto on February 2nd and Vesta on February 6th. Browse www.lunar-occultations.com/iota/ for information on these events and upcoming lunar occultations. Click on www.calendar-12.com/moon_calendar/2019/february for a February 2019 lunar calendar. Visit saberdoesthestars.wordpress.com/2011/07/05/saber-does-the-stars/ for tips on spotting extreme crescent Moons. 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 the constellation of Capricornus on February 1st. It enters Aquarius on February 16th.
Brightness, apparent size, illumination, distance from the Earth in astronomical units, and location data for the planets and Pluto on February 1: Mercury (magnitude -1.5, 4.8", 100% illuminated, 1.40 a.u., Capricornus), Venus (magnitude -4.3, 19.2", 62% illuminated, 0.87 a.u., Sagittarius), Mars (magnitude +0.9, 6.1", 89% illuminated, 1.53 a.u., Pisces), Jupiter (magnitude -1.9, 33.6", 99% illuminated, 5.86 a.u., Ophiuchus), Saturn (magnitude +0.6, 15.2", 100% illuminated, 10.93 a.u., Sagittarius), Uranus (magnitude +5.8, 3.5", 100% illuminated, 20.28 a.u. on February 15th, Pisces), Neptune (magnitude +8.0, 2.2", 100% illuminated, 30.87 a.u. on February 15th, Aquarius), and Pluto (magnitude +14.3, 0.1", 100% illuminated, 34.30 a.u. on February 15th, Sagittarius).
Mercury can be seen in the west and Mars, Uranus, and Neptune in the southwest in the evening sky. In the morning sky, Venus, Jupiter, and Saturn lie in the southeast.
Mercury is at its greatest heliocentric latitude south on February 1st. It reappears from superior conjunction low in the west at dusk around February 11th or February 12th. Mercury is at the ascending node on February 20th and at perihelion on February 25th. The speediest planet reaches greatest eastern elongation on the North American evening of February 26th. Mercury is approximately nine degrees above the horizon 45 minutes after sunset at that time. This will be the best evening apparition of 2019 for northern hemisphere observers.
Venus is visible low in the southeast before sunrise. Observers in the southern hemisphere are favored. Venus decreases in apparent size from 19.2 arc seconds to 15.7 arc seconds and increases in illumination from 62% to 72% this month. It will remain in the gibbous phase for the rest of the year. The brightest planet passes two degrees north of M20 (the Trifid Nebula) on February 4th, two degrees south of the open cluster M25 and three degrees north of the globular cluster M22 on February 10th and February 11th, and just over one degree north of Saturn on February 18th. The planet’s eastward motion of about one degree per day places it less than three degrees north-northwest of the globular cluster M75 by the end of February.
Mars dims from magnitude +0.9 to magnitude +1.2 and shrinks in apparent diameter from 6.1 arc seconds to 5.3 arc seconds by the end of February. A crescent Moon passes six degrees southeast of Mars on February 10th. Mars departs Pisces and enters Aries on February 12th.
As February begins, Jupiter rises after 3:30 a.m. local time. By the end of February, the gas giant planet rises at 2:00 a.m. local time. It brightens from magnitude -1.9 to magnitude -2.0 and increases in apparent diameter from 33.6 arc seconds to 36.1 arc seconds this month. The waning crescent Moon passes two degrees to the north of Jupiter on February 27th. A shadow transit by the Galilean satellite Io takes place on the morning of February 6th starting at 10:45 UT (5:45 a.m. EST). Just over an hour later at 11:49 UT (6:49 a.m. EST), Io begins to transit the planet. Callisto lies due north of Jupiter that morning. 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 February 2019 issue of Sky & Telescope. Click on www.skyandtelescope.com/observing/interactive-sky-watching-tools/ or consult pages 50 and 51 of the February 2019 issue of Sky & Telescope to determine transit times of the central meridian by the Great Red Spot.
As the month ends, Saturn shines at magnitude +0.6. Its ring system spans 35 arc seconds and is inclined 24 degrees from edge-on. The waning crescent Moon passes less than one degree north of Saturn of February 2nd. Saturn and Venus lie within 2.5 degrees of each other from February 16th to February 20th. Saturn is 1.1 degrees south of Venus on February 18th. The Ringed Planet rises shortly after 4:00 a.m. local time by the end of February. For information on the satellites of Saturn, browse www.skyandtelescope.com/observing/interactive-sky-watching-tools/
Uranus enters Aries on February 5th, where it will remain for the remainder of the year. On February 1st, Uranus is located seven degrees east-northeast of Mars. The angular distance between the two planets decreases by more than one half degree per day. The gap narrows to 1.5 degrees by February 10th. On February 12th, Uranus is 1.0 degree south-southeast of Mars. The following day it is 1.1 degrees south of Mars.
Neptune lies 0.8 degree due north of the fifth-magnitude star 83 Aquarii on February 1st. The eighth planet moves to a position 0.9 degree northeast of 83 Aquarii a week later. Neptune disappears from view by the second week of February.
See curtrenz.com/uranep.html for additional information on the two outer planets.
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.
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 not visible this month.
For more on the planets and how to locate them, browse www.nakedeyeplanets.com/
Comet 46P/Wirtanen travels southeastward through Ursa Major during February. It passes less than one half of a degree west of the third-magnitude star Theta Ursa Majoris on February 10th and February 11th. Comet C/2018 Y1 (Iwamoto) will reach perihelion in early February. This speedy comet comes close to the spiral galaxy M104 (the Sombrero Galaxy) in Virgo on February 2nd and very close to the barred spiral galaxy M95 in Leo on February 10th. Comet Iwamoto will pass within 45 million kilometers (28 million miles) of the Earth on February 10th and reach a maximum predicted brightness of seventh magnitude. Click on earthsky.org/astronomy-essentials/c-2018-y1-iwamoto-jan-feb-2019 for more on this comet. Visit cometchasing.skyhound.com/ and www.aerith.net/comet/future-n.html for additional information on comets visible this month.
Asteroid 532 Herculina heads north-westward through Leo and Cancer this month. It reaches a peak magnitude of +8.9 when it reaches opposition on February 6th. Other asteroids brighter than magnitude +11.0 that reach opposition this month include 129 Antigone (magnitude +10.8) in Leo on February 17th and 349 Dembowska (magnitude +10.3) in Leo on February 27th. On the morning of February 11th, the sixteenth-magnitude asteroid 301 Bavaria occults the ninth-magnitude star HD 144893 (HIP 79094) in Scorpius for a maximum of 2.3 seconds for observers in parts of North America. Browse asteroidoccultation.com/2019_02/0211_301_62730.htm for more on this occultation. The seventeenth-magnitude asteroid 4388 occults the first-magnitude star Sirius (Alpha Canis Majoris) for a maximum of 1.8 seconds on the night of February 18th/19th from parts of North America. See asteroidoccultation.com/2019_02/0219_4388_62950.htm for additional information on this event and asteroidoccultation.com/2019_02_si.htm for information on other asteroid occultation events taking place this month. Consult www.curtrenz.com/asteroids.html to learn more about a number of asteroids
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 the month can be downloaded at www.skymaps.com/downloads.html and www.telescope.com/content.jsp?pageName=Monthly-Star-Chart
The famous eclipsing variable star Algol (Beta Persei) is at a minimum, decreasing in magnitude from 2.1 to 3.4, on February 1st, 4th, 7th, 9th, 12th, 15th, 18th, 21st, 24th, and 27th. Consult page 50 of the February 2019 issue of Sky & Telescope for the times of the minima. The Demon Star is at minimum brightness for approximately two hours centered at 11:55 p.m. EST on February 3rd (4:55 UT on February 4th), at 8:45 p.m. EST on February 6th (1:45 UT on February 7th), at 1:41 a.m. EST on February 24th (6:41 UT on February 24th), and at 10:30 p.m. EST on February 26th (3:30 UT on February 27th). 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/
Forty binary and multiple stars for February: 41 Aurigae, Struve 872, Otto Struve 147, Struve 929, 56 Aurigae (Auriga); Nu-1 Canis Majoris, 17 Canis Majoris, Pi Canis Majoris, Mu Canis Majoris, h3945, Tau Canis Majoris (Canis Major); Struve 1095, Struve 1103, Struve 1149, 14 Canis Minoris (Canis Minor); 20 Geminorum, 38 Geminorum, Alpha Geminorum (Castor), 15 Geminorum, Lambda Geminorum, Delta Geminorum, Struve 1108, Kappa Geminorum (Gemini); 5 Lyncis, 12 Lyncis, 19 Lyncis, Struve 968, Struve 1025 (Lynx); Epsilon Monocerotis, Beta Monocerotis, 15 (S) Monocerotis (Monoceros); Struve 855 (Orion); Struve 1104, k Puppis, 5 Puppis (Puppis)
Notable carbon star for February: BL Orionis (Orion)
Fifty deep-sky objects for February: NGC 2146, NGC 2403 (Camelopardalis); M41, NGC 2345, NGC 2359, NGC 2360, NGC 2362, NGC 2367, NGC 2383 (Canis Major); M35, NGC 2129, NGC 2158, NGC 2266, NGC 2355, NGC 2371-72, NGC 2392, NGC 2420 (Gemini); NGC 2419 (Lynx); M50, NGC 2232, NGC 2237, NGC 2238, NGC 2244, NGC 2245, NGC 2251, NGC 2261, NGC 2264, NGC 2286, NGC 2301, NGC 2311, NGC 2324, NGC 2335, NGC 2345, NGC 2346, NGC 2353 (Monoceros); NGC 2169, NGC 2174, NGC 2194 (Orion); M46, M47, M93, Mel 71, NGC 2421, NGC 2423, NGC 2438, NGC 2439, NGC 2440, NGC 2467, NGC 2506, NGC 2509 (Puppis)
Top ten binocular deep-sky objects for February: M35, M41, M46, M47, M50, M93, NGC 2244, NGC 2264, NGC 2301, NGC 2360
Top ten deep-sky objects for February: M35, M41, M46, M47, M50, M93, NGC 2261, NGC 2362, NGC 2392, NGC 2403
Challenge deep-sky object for February: IC 443 (Gemini)
The objects listed above are located between 6:00 and 8:00 hours of right ascension.