June Celestial Calendar by Dave Mitsky
All times, unless otherwise noted, are UT (subtract four hours and, when appropriate, one calendar day for EDT)
6/1 The Moon is 3.1 degrees south-southeast of Venus at 21:00
6/2 The Moon is 7.9 degrees south-southeast of the bright open cluster M45 (the Pleiades or Subaru) in Taurus at 13:00
6/3 Mercury is at its greatest heliocentric latitude north today; asteroid 2 Pallas is stationary at 2:00; the Moon is 2.3 degrees north of the first-magnitude star Aldebaran (Alpha Tauri) at 6:00; New Moon (lunation 1193) occurs at 10:02
6/4 The Moon is 3.7 degrees south of Mercury at 17:00
6/5 A double Galilean satellite shadow transit (Ganymede’s shadow precedes Io’s) begins at 0:29; the Moon is 1.6 degrees south of Mars at 15:00; the Moon is at the ascending node (longitude 107.9 degrees) at 23:00
6/6 Mercury is 1.2 degrees north of the bright open cluster M35 in Gemini at 1:00; the Moon is 6.2 degrees south of the first-magnitude star Pollux (Beta Geminorum) at 10:00
6/7 The Moon makes a close approach to the bright open cluster M44 (the Beehive Cluster or Praesepe) in Cancer at 8:00; the Moon is at perigee, subtending 32' 26" from a distance of 368,504 kilometers (228,978 miles), at 23:15
6/8 The Moon is 3.0 degrees north-northeast of the first-magnitude star Regulus (Alpha Leonis) at 22:00
6/9 Venus is 5.1 degrees south-southeast of the bright open cluster M45 at 5:00
6/10 The Purbach Cross or Lunar X, an X-shaped illumination effect involving various rims and ridges between the craters La Caille, Blanchinus, and Purbach, is predicted to be visible at 4:17; First Quarter Moon occurs at 5:59; Jupiter (magnitude -2.6, apparent size 46.0") is at opposition at 16:00
6/12 A double Galilean satellite shadow transit (Io’s shadow precedes Ganymede’s) begins at 3:33; the Moon is 7.3 degrees north-northeast of the first-magnitude star Spica (Alpha Virginis) at 18:00
6/13 The equation of time, which yields the difference between mean solar time and apparent solar time, equals 0 at 10:00
6/14 The earliest sunrise of the year at latitude 40 degrees north occurs today
6/15 The Moon is 0.9 degree north of dwarf planet/asteroid 1 Ceres, with an occultation taking place in Japan, northern and eastern China, northeastern Kazakhstan, and central and eastern Russia, at 15:00
6/16 The Moon is 7.8 degrees north-northeast of the first-magnitude star Antares (Alpha Scorpii) at 5:00; the Moon is 2.0 degrees north-northeast of Jupiter at 20:00
6/17 The earliest morning twilight of the year at latitude 40 degrees north occurs today; Full Moon, known as the Rose or Strawberry Moon, occurs at 8:31; Venus is 5.0 degrees north of the first-magnitude star Aldebaran (Alpha Tauri) at 21:00
6/18 Mercury (magnitude +0.2) is 0.2 degree north of Mars (magnitude +1.8) at 14:00
6/19 The Moon is at the descending node (longitude 287.6 degrees) at 2:00; the Moon is 0.4 degree south of Saturn, with an occultation taking place in southern Africa, the Antarctic Peninsula, southern South America, and Easter Island, at 4:00; the Moon is 0.1 degree south of Pluto, with an occultation taking place in western South America, Central America, southern Polynesia, southern Micronesia, northeastern Australia, and Melanesia, at 11:00; Mercury is 5.4 degrees south-southwest of Pollux at 14:00
6/21 Mars is 5.5 degrees south of Pollux at 8:00; the Sun reaches an ecliptic longitude of 90 degrees and the northern hemisphere summer solstice occurs at 15:56
6/22 The Sun enters Gemini, at longitude 90.43 degrees on the ecliptic, at 3:00; Neptune is stationary at 4:00
6/23 The Moon is at apogee, subtending 29' 32" from a distance of 404,548 kilometers (251,375 miles), at 7:50; Mercury is at greatest eastern elongation (25 degrees) at 23:00
6/24 The latest evening twilight of the year at latitude 40 degrees north occurs today; the Moon is 3.6 degrees south-southeast of Neptune at 4:00
6/25 Last Quarter Moon occurs at 9:47
6/26 Mercury is at the descending node today; the Curtiss Cross, an X-shaped illumination effect located between the craters Parry and Gambart, is predicted to be visible at 6:33
6/27 The latest sunset of the year at latitude 40 degrees north occurs today
6/28 The Moon is 4.5 degrees south-southeast of Uranus at 2:00
6/29 The Moon is 7.9 degrees south-southeast of the bright open cluster M45 at 23:00
6/30 The Moon is 2.3 degrees north of Aldebaran at 15:00
Giovanni Cassini (1625-1712), John Dollond (1706-1761), Charles Messier (1730-1817), William Lassell (1799-1880), George Ellery Hale (1868-1938), and Carolyn Shoemaker (1929) were born this month.
The British astronomer Edmund Halley discovered M13 on June 1, 1714. The French astronomer Nicolas Louis de Lacaille discovered the globular cluster M55 on June 16, 1752. A transit of the Sun by Venus was observed by Austrian, British, and French astronomers from various parts of the world on June 6, 1761. The French astronomer Charles Messier discovered the globular cluster M14 on June 1st, 1764, the emission and reflection nebula M20 (the Trifid Nebula) on June 5, 1764, and the open cluster M23 on June 20, 1764. The globular cluster M62 was discovered by Charles Messier on June 7, 1771. The French astronomer Pierre Méchain discovered his first deep-sky object, the spiral galaxy M63 (the Sunflower Galaxy), on June 14, 1779. The German/English astronomer William Herschel discovered the globular cluster NGC 6288 on June 24, 1784. Neptune was independently discovered by the British astronomer John Couch Adams on June 5, 1846. The Italian astronomer Giovanni Battista Donati discovered Comet C/1858 L1 (Donati), the first comet to be photographed, on June 2, 1858. A large storm on Saturn was observed by the American astronomer E. E. Barnard. The Tunguska event occurred on June 30, 1908. The largest known solar flare was recorded on June 27, 1984. The Georgian astronomer Givi Kimeridze discovered a Type Ia supernova in the spiral galaxy M58 on June 28, 1989. Namaka, a satellite of the dwarf planet Haumea, was discovered on June 30, 2005. Kerberos, Pluto’s fourth satellite, was discovered by the Hubble Space Telescope team on June 28, 2011.
The minor Boötid meteor shower (5 per hour) peaks on the morning of June 27th. The source of Boötid meteors is the periodic comet 7P/Pons-Winnecke. The radiant lies in northern Boötes at right ascension 14 hours 56 minutes, declination 48 degrees. Browse http://www.spaceweat...unebootids.html for additional information.
Information on Iridium flares and passes of the ISS, the Tiangong-2, the USAF’s X-37B, the HST, and other satellites can be found at http://www.heavens-above.com/
The Moon is 26.9 days old, is illuminated 7.6%, subtends 30.3 arc minutes, and is located in Cetus on June 1st at 0:00 UT. The June lunar month is 29 days 09 hours 14 minutes in length. The Moon is at its greatest northern declination of +22.2 degrees on June 6th and at its greatest southern declination of -22.3 degrees on June 19th. Longitudinal libration is at a maximum of +5.1 degrees on June 16th and a minimum of -5.2 degrees on June 2nd and -6.1 degrees on June 29th. Latitudinal libration is at a maximum of +6.8 degrees on June 27th and a minimum of -6.7 degrees on June 12th. New Moon occurs on June 3rd. On June 7th, the Moon passes very near the bright open cluster M44. The Moon is at perigee on June 7th (distance 57.78 Earth-radii) and at apogee on June 23rd (distance 63.43 Earth-radii). The Moon occults 1 Ceres on June 15th and Saturn and Pluto on June 19th from certain parts of the world. See http://www.lunar-occ...ota/iotandx.htm for information on lunar occultations taking place this month. Visit http://saberdoesthes...does-the-stars/ for tips on spotting extreme crescent Moons. Click on http://www.calendar-...endar/2019/june for a lunar phase calendar. Times and dates for the lunar light rays predicted to occur this month are available at http://www.lunar-occ...o/rays/rays.htm
The Sun is located in Taurus on June 1st. It enters Gemini on June 22nd. The Sun reaches its farthest position north for the year on June 21st. There are 15 hours and one minute of daylight at latitude 40 degrees north on June 21st, the day of the summer solstice. At latitude 40 degrees north, the earliest sunrise occurs on June 14th and the latest sunset on June 27th. For an explanation of why this occurs, click on https://earthsky.org/?p=4027
Brightness, apparent size, illumination, distance from the Earth in astronomical units, and location data for the planets and Pluto on June 1st: Mercury (-1.1, 5.5", 87% illuminated, 1.23 a.u., Taurus), Venus (magnitude -3.8, 10.5", 94% illuminated, 1.59 a.u., Aries), Mars (magnitude +1.8, 3.9", 98% illuminated, 2.43 a.u., Gemini), Jupiter (magnitude -2.6, 45.8", 100% illuminated, 4.30 a.u., Ophiuchus), Saturn (magnitude +0.3, 18.0", 100% illuminated, 9.25 a.u., Sagittarius), Uranus on June 16th (magnitude +5.9, 3.4", 100% illuminated, 20.49 a.u., Aries), Neptune on June 16th (magnitude +7.9, 2.3", 100% illuminated, 29.82 a.u., Aquarius), and Pluto on June 16th (magnitude +14.2, 0.1", 100% illuminated, 32.93 a.u., Sagittarius).
Mercury and Mars are in the northwest and Jupiter is in the southeast in the evening sky. At midnight, Jupiter lies in the south and Saturn lies in the southeast. Venus in the northeast, Jupiter and Saturn can be found in the southwest, Uranus in the east, and Neptune in the southeast at dawn.
Mercury grows in apparent size from 5.5 to 9.2 arc seconds but decreases in magnitude from -1.1 to +0.9. Mercury reaches its highest heliocentric latitude on June 3rd. On June 4th, a very thin two-day-old waxing crescent Moon passes four degrees south of the planet at sunset. Mercury is located 1.2 degrees north of the bright open cluster M35 on June 8th. Mercury and Mars are separated by 28 arc minutes on June 17th and just 18 arc minutes during their closest conjunction in 13 years on June 18th. Mercury shines at magnitude +0.2, which is five times brighter than the Red Planet, and subtends 7.4 arc seconds, which is twice the apparent size of Mars at the time. As June progress, Mercury climbs higher into the sky and Mars loses altitude. The speediest planet reaches its greatest eastern elongation on June 23rd, when it is located at an altitude of 11 degrees 30 minutes after sunset.
Brilliant Venus and the waning crescent Moon lie six degrees apart and six degrees above the horizon 30 minutes before sunrise on June 1st. The planet is at an elongation of 20 degrees at the time. Aldebaran is approximately five degrees to the lower right of Venus on the morning of June 18th. Venus is just three degrees above the horizon one half-hour before the Sun rises on June 30th.
During June, Mars shines faintly at magnitude +1.8 and shrinks to 3.7 arc seconds, just three arc seconds larger than Uranus. The waxing crescent Moon passes 1.6 degrees south of Mars on June 5th. Mars and Mercury undergo a very close conjunction on June 18th.
Saturn rises at about 11:00 p.m. local daylight time on June 1st. The planet shines at magnitude +0.2 and subtends 18.2 arc seconds at its equator, while its rings span 41 arc seconds and are inclined 24 degrees. The waxing gibbous Moon passes less than one degree south of Saturn, with an occultation occurring in some parts of the world, on June 19th. Eighth-magnitude Titan passes north of Saturn on the mornings of June 13th and June 29th and south of the planet on the mornings of June 5th and June 21st. For information on Saturn’s satellites, browse http://www.skyandtel...atching-tools/
By the end of the month, Uranus rises at about 2:00 a.m. local daylight time. The ice giant is situated in southern Aries, some ten degrees south of the first-magnitude star Hamal (Alpha Arietis) and 2.4 degrees south of the sixth-magnitude star 19 Arietis. The waxing gibbous Moon passes five degrees north of Uranus on June 27th. Visit http://www.bluewater...anus_2019_1.pdf and http://www.nakedeyep...htm#finderchart for finder charts.
Neptune rises shortly after 1:00 a.m. local daylight time by mid-June. The eighth planet lies 1.2 degree east-northeast of the fourth-magnitude star Phi Aquarii on June 1st. Neptune reaches its first stationary point on June 22nd, when it will be less than 1.5 degrees northeast of Phi Aquarii and less than 0.5 degree south of the sixth-magnitude star 96 Aquarii.
Finder charts for Uranus and Neptune are available at https://s22380.pcdn....p-2019-2020.pdf
Pluto resides in northeastern Sagittarius. The waxing gibbous Moon passes 0.1 degree south of Pluto, with an occultation occurring in some parts of the world, on June 19th. Finder charts can be found at http://www.bluewater...9/Pluto2019.jpg and on pages 48 and 49 of the July 2019 issue of Sky & Telescope and page 243 of the RASC Observer’s Handbook 2019.
For more on the planets and how to locate them, browse http://www.nakedeyeplanets.com/
Comet C/2018 N2 (ASASSN) travels northeastward through northeastward through northeastern Cetus during June. The faint comet lies about 1.5 degrees to the east of the fourth-magnitude star Xi Ceti on June 30th. Visit http://cometchasing.skyhound.com/ and http://www.aerith.ne...t/future-n.html for information on comets visible this month.
Shining at ninth magnitude, asteroid 2 Pallas glides southeastward through eastern Coma Berenices this month. It lies about two degrees to the west of the sixth-magnitude star 2 Boötes on June 21st. The main belt asteroid passes very close to similarly bright stars on June 12th and June 26th. Asteroids brighter than magnitude +11.0 that reach opposition this month include 410 Chloris (magnitude +10.3) on June 14th, 22 Kalliope (magnitude +10.8) on June 15th, and 914 Palisana (magnitude +10.8) on June 28th. Information on asteroid occultations taking place this month is available at http://www.asteroido.../2019_06_si.htm
For more on the planets and how to locate them, browse http://www.nakedeyeplanets.com/
Various events taking place within our solar system are discussed at http://www.bluewater...ed-4/index.html
Data on current supernovae can be found at http://www.rochester...y.org/snimages/
Information pertaining to observing some of the more prominent Messier galaxies can be found at http://www.cloudynig...ur-astronomers/
Forty binary and multiple stars for June: Struve 1812, Kappa Bootis, Otto Struve 279, Iota Bootis, Struve 1825, Struve 1835, Pi Bootis, Epsilon Bootis, Struve 1889, 39 Bootis, Xi Bootis, Struve 1910, Delta Bootis, Mu Bootis (Bootes); Struve 1803 (Canes Venatici); Struve 1932, Struve 1964, Zeta Coronae Borealis, Struve 1973, Otto Struve 302 (Corona Borealis); Struve 1927, Struve 1984, Struve 2054, Eta Draconis, 17-16 Draconis, 17 Draconis (Draco); 54 Hydrae (Hydra); Struve 1919, 5 Serpentis, 6 Serpentis, Struve 1950, Delta Serpentis, Otto Struve 300, Beta Serpentis, Struve 1985 (Serpens Caput); Struve 1831 (Ursa Major); Pi-1 Ursae Minoris (Ursa Minor); Struve 1802, Struve 1833, Phi Virginis (Virgo)
Notable carbon star for June: V Coronae Borealis
Fifty deep-sky objects for June: NGC 5466, NGC 5676, NGC 5689 (Bootes); M102 (NGC 5866), NGC 5678, NGC 5879, NGC 5905, NGC 5907, NGC 5908, NGC 5949, NGC 5963, NGC 5965, NGC 5982, NGC 5985, NGC 6015 (Draco); NGC 5694 (Hydra); NGC 5728, NGC 5791, NGC 5796, NGC 5812, NGC 5861, NGC 5878, NGC 5897 (Libra); M5, NGC 5921, NGC 5957, NGC 5962, NGC 5970, NGC 5984 (Serpens Caput); M101, NGC 5473, NGC 5474, NGC 5485, NGC 5585, NGC 5631 (Ursa Major); NGC 5566, NGC 5634, NGC 5701, NGC 5713, NGC 5746, NGC 5750, NGC 5775, NGC 5806, NGC 5813, NGC 5831, NGC 5838, NGC 5846, NGC 5850, NGC 5854, NGC 5864 (Virgo)
Top ten deep-sky objects for June: M5, M101, M102, NGC 5566, NGC 5585, NGC 5689, NGC 5746, NGC 5813, NGC 5838, NGC 5907
Top five deep-sky binocular objects for June: M5, M101, M102, NGC 5466, NGC 5907
Challenge deep-sky object for June: Abell 2065 (Corona Borealis)
The objects listed above are located between 14:00 and 16:00 hours of right ascension.