Dave Mitsky
02-May-2007, 03:29 PM
May Calendar by Dave Mitsky
All times, unless otherwise noted, are UT (subtract four hours and, when appropriate, one calendar day for EDT)
5/1 May Day, or Beltane, a cross-quarter day
5/2 Full Moon, known as the Milk or Planting Moon, occurs at 10:09
5/3 Mercury is in inferior conjunction with the Sun at 4:00
5/4 The Moon is 0.5 degree south of the first magnitude star Antares (Alpha Scorpii), with an occultation taking place in New Zealand, Tasmania, a portion of Antarctica, and southeast Africa, at 18:00
5/5 Asteroid 3 Juno is stationary today; the peak of the Eta Aquarid meteor shower (10/hour for northern hemisphere observers) occurs at 11:00; Jupiter is 6 degrees north of the Moon at 12:00
5/6 A maximum lunar libration of 8.7 degrees occurs at 21:00
5/9 Mars is its greatest heliocentric latitude south today; Mercury is at aphelion today
5/10 Last Quarter Moon occurs at 4:27; Venus is 1.7 degrees north of the center of the bright open cluster M35 in Gemini at 5:00; Neptune is 1.8 degrees north of the Moon at 8:00
5/11 Venus is its greatest heliocentric latitude north today
5/12 Uranus is 1.3 degrees south of the Moon, with an occultation taking place in most of Great Britain and eastern Greenland, at 7:00
5/13 Mars is 3 degrees south of the Moon at 1:00
5/14 A minimum lunar libration of 4.4 degrees occurs at 1:00
5/15 The Moon is at perigee, subtending 33'15" from a distance of 359,392 km, at 15:00
5/16 New Moon (lunation 1044) occurs at 19:27; Mercury is 7 degrees north of the first magnitude star Aldebaran (Alpha Tauri) at 21:00
5/18 Mercury is 3 degrees south of the Moon at 0:00
5/19 Mercury is at its greatest heliocentric latitude north today
5/20 Venus is 1.7 degrees south of the Moon at 1:00; Venus is 0.75 degree south of the Moon at 2:30; a maximum lunar libration of 8.8 degrees occurs at 3:00
5/21 The Moon is 1.4 degrees north of the bright open cluster M44 (the Beehive Cluster or Praesepe) in Cancer at 21:00
5/22 Saturn is 0.8 degree south of the Moon, with an occultation taking place in the British Isles, Europe, northeast Africa, northwest Asia, the Arctic, and northwest Canada, at 19:00
5/23 The Moon is 0.7 degree north of the first magnitude star Regulus (Alpha Leonis), with an occultation taking place in most of Asia, northeast Europe, Great Britian, Greenland, and the northeastern tip of Canada, at 16:00; First Quarter Moon occurs at 21:03
5/25 Neptune is stationary at 6:00
5/26 A minimum lunar libration of 3.7 degrees occurs at 18:00
5/27 The Moon is at apogee, subtending 29'28" from a distance of 405,460 km, at 22:00
5/28 The Moon is 1.4 degree south of the first magnitude star Spica (Alpha Virginis) at 6:00
5/30 Asteroid 4 Vesta (magnitude 5.4) is at opposition at 14:00; Venus is 4 degrees south of the first magnitude star Pollux (Beta Geminorum) at 19:00; Mercury is 1.1 degrees north of M35 at 20:00
The May 5th peak of the Eta Aquarids, a minor meteor shower produced by debris from the famous periodic comet 1P/Halley, is compromised by a waning gibbous Moon. The Eta Aquarid meteor shower favors observers in the southern hemisphere but the Orionids, another shower that is caused by Comet Halley, favors the northern hemisphere in October.
The Moon is 13.5 days old on May 1 at 0:00 UT. The Moon is at its greatest northern declination on May 18 (+28 degree) and its greatest southern declination on May 6 (-28 degrees). Ignoring Universal Time conventions, a second Full Moon, a so-called Blue Moon, takes place this month at 9:04 p.m. EDT on May 31. Times and dates for the lunar light rays predicted to occur in May are available at http://www.lunar-occultations.com/rlo/rays/rays.htm
Brightness, apparent size, illumination, distance from the Earth in astronomical units, and location data for the planets and Pluto on May 1: Mercury (-2.0 magnitude, 5.1", 100% illuminated, 1.3 a.u., Aries), Venus (-4.1 magnitude, 16.4", 68% illuminated, 1.0 a.u., Taurus), Mars (1.0 magnitude, 5.3", 91% illuminated, 1.8 a.u., Aquarius), Jupiter (-2.5 magnitude, 43.8", 100% illuminated, 4.5 a.u., Ophiuchus), Saturn (0.4 magnitude, 18.4", 100% illuminated, 9.0 a.u., Leo), Uranus (5.9 magnitude, 3.4", 100% illuminated, 20.7 a.u., Aquarius), Neptune (7.9 magnitude, 2.3", 100% illuminated, 30.2 a.u., Capricornus), and Pluto (13.9 magnitude, 0.1", 100% illuminated, 30.7 a.u., Sagittarius).
Visibility of the classical planets at mid-month for observers at 40 degrees north: Mercury can be seen in evening twilight after mid-month; Venus is dominant in the western sky after sundown and sets at midnight; Mars rises around 4:00 a.m. EDT; Jupiter clears the horizon at approximately 10:00 p.m. EDT and transits the meridian at 3:00 a.m. EDT; Saturn can be seen in the southwest after nightfall and sets at about 2:00 a.m. EDT.
Mercury's best evening apparition of the year begins this month. It may be visible again very low in the west-northwest as early as May 11 after undergoing inferior conjunction on May 3. The speedy planet lies 7 degrees north of Aldebaran on May 16 and 2.5 degrees south of the Moon the next evening. On May 23, Mercury is positioned halfway between third magnitude Zeta Tauri and second magnitude Beta Tauri as it shines at -0.3 magnitude some 7 degrees above the horizon in the west-northwest. Mercury's disk increases in size but decreases in illumination as the month progresses and by May 27 only half of the planet is sunlit. The planet's brightness drops by almost two full magnitudes during the course of the month.
Like Mercury, Venus shrinks in illumination but increases in apparent size. By the end of May, it is 5" larger but is only 55% illuminated.
Mars reaches first magnitude status this month but at 6" in apparent size is still too small for fruitful observation. It is situated low in the east-southeast at dawn. The Red Planet begins the month in Aquarius. On May 9, it heads into Pisces and then enters Cetus on May 24. By May 29, Mars is back once again in Pisces.
Jupiter rises not long after sunset by the end of May. The giant planet travels westward through Ophiuchus towards Antares in Scorpius. Jupiter begins the month eleven degrees away from the first magnitude red giant star and is eight degrees distant by the end of May. Click on http://skyandtelescope.com/observing/objects/planets/article_107_1.asp to determine transit times of the central meridian by the Great Red Spot. Data on the Galilean satellites is available at http://skytonight.com/observing/objects/javascript/3307071.html
Saturn reaches eastern quadrature during the second week of May. As a result, Saturn's shadow falls on its rings, giving the planet an enhanced three-dimensional appearance. The rings have an angular extent of 41" by 11" and the disk 18" this month. On the night of May 22, Titan (magnitude 8.8) is due east of Saturn. Rhea, Dione, and Tethys all shine at around tenth magnitude while the planet hugging Enceladus is a difficult target at nearly twelfth magnitude. Bizarre Iapetus is west of Saturn in early May and then swings to the east of the planet, decreasing in brightness from eleventh to twelfth magnitude as it does so. Titan and Iapetus are less than one arc minute apart on May 7. The position of Iapetus in relation to Saturn is as follows: May 2 (5" west), May 4 (1" east), May 8 (12" east), May 12 (22" east), May 18 (33" east), May 24 (37" east), and May 30 (34" east). For further information on Saturn's satellites, browse http://skytonight.com/observing/objects/javascript/3308506.html
Uranus and Neptune both rise prior to dawn and are therefore still poorly placed for observation. Uranus is 1.7 degrees northwest of Mars and is less than 30' to the southwest of the fourth magnitude star Phi Aquarii on May 1.
The dwarf planet Pluto is located in northwestern Sagittarius near the border with Serpens Cauda. On May 1, Pluto is 2.7 degrees north of the open cluster M23 and 6 degrees west of the bright emission nebula M17 (the Checkmark, Horseshoe, Lobster, Omega, or Swan Nebula).
Asteroid 4 Vesta reaches opposition on May 30, seventeen days before perihelion. This makes the minor solar system body almost a full magnitude brighter than normal and a fairly easy naked-eye target from a dark site until the end of June. Vesta is located to the northwest of Eta Ophiuchi and to the southeast of Zeta Ophiuchi on May 1. It passes westward through Ophiuchus during May and is situated less than two degrees south of the eighth magnitude globular cluster M107 on May 30.
Eighty binary and multiple stars for May: 1 Bootis, Struve 1782, Tau Bootis, Struve 1785, Struve 1812 (Bootes); 2 Canum Venaticorum, Struve 1624, Struve 1632, Struve 1642, Struve 1645, 7 Canum Venaticorum, Alpha Canum Venaticorum (Cor Caroli), h2639, Struve 1723, 17 Canum Venaticorum, Otto Struve 261, Struve 1730, Struve 1555, h1234, 25 Canum Venaticorum, Struve 1769, Struve 1783, h1244 (Canes Venatici); 2 Comae Berenices, Struve 1615, Otto Struve 245, Struve 1633, 12 Comae Berenices, Struve 1639, 24 Comae Berenices, Oto Struve 253, Struve 1678, 30 Comae Berenices, Struve 1684, Struve 1685, 35 Comae Berenices, Burnham 112, h220, Struve 1722, Beta Comae Berenices, Burnham 800, Otto Struve 266, Struve 1748 (Coma Berenices); h4481, h4489, Struve 1604, Delta Corvi, Burnham 28, h1218, Struve 1669 (Corvus); H N 69, h4556 (Hydra); Otto Struve 244, Struve 1600, Struve 1695, Zeta Ursae Majoris (Mizar), Struve 1770, Struve 1795, Struve 1831 (Ursa Major); Struve 1616, Struve 1627, 17 Virginis, Struve 1648, Struve 1658, Struve 1677, Struve 1682, Struve 1689, Struve 1690, 44 Virginis, Struve 1719, Theta Virginis, 54 Virginis, Struve 1738, Struve 1740, Struve 1751, 81 Virginis, Struve 1764, Struve 1775, 84 Virginis, Struve 1788 (Virgo)
Challenge binary star for May: 48 Virginis
One hundred and sixty-five deep-sky objects for May: NGC 5248 (Bootes); M3, M51, M63, M94, M106, NGC 4111, NGC 4138, NGC 4143, NGC 4151, NGC 4214, NGC 4217, NGC 4244, NGC 4346, NGC 4369, NGC 4449, NGC 4485, NGC 4490, NGC 4618, NGC 4631, NGC 4656, NGC 4868, NGC 5005, NGC 5033, NGC 5297, NGC 5353, NGC 5354, Up 1 (Canes Venatici); Mel 111, M53, M64, M85, M88, M91, M98, M99, M100, NGC 4064, NGC 4150, NGC 4203, NGC 4212, NGC 4251, NGC 4274, NGC 4278, NGC 4293, NGC 4298, NGC 4302, NGC 4314, NGC 4350, NGC 4414, NGC 4419, NGC 4448, NGC 4450, NGC 4459, NGC 4473, NGC 4474, NGC 4494, NGC 4559, NGC 4565, NGC 4651, NGC 4689, NGC 4710, NGC 4725, NGC 4874, NGC 5053 (Coma Berenices); NGC 4027, NGC 4038-9, NGC 4361 (Corvus); M68, M83, NGC 4105, NGC 4106, NGC 5061, NGC 5101, NGC 5135 (Hydra); M40, NGC 4036, NGC 4041, NGC 4051, NGC 4062, NGC 4085, NGC 4088, NGC 4096, NGC 4100, NGC 4144, NGC 4157, NGC 4605, NGC 5308, NGC 5322 (Ursa Major); M49, M58, M59, M60, M61, M84, M86, M87, M89, M90, M104, NGC 4030, NGC 4073, NGC 4168, NGC 4179, NGC 4206, NGC 4215, NGC 4216, NGC 4224, NGC 4235, NGC 4260, NGC 4261, NGC 4267, NGC 4281, NGC 4339, NGC 4343, NGC 4365, NGC 4371, NGC 4378, NGC 4380, NGC 4387, NGC 4388, NGC 4402, NGC 4429, NGC 4435, NGC 4438, NGC 4517, NGC 4526, NGC 4535, NGC 4536, NGC 4546, NGC 4550, NGC 4551, NGC 4567, NGC 4568, NGC 4570, NGC 4593, NGC 4596, NGC 4636, NGC 4638, NGC 4639, NGC 4643, NGC 4654, NGC 4666, NGC 4697, NGC 4698, NGC 4699, NGC 4753, NGC 4754, NGC 4760, NGC 4762, NGC 4866, NGC 4900, NGC 4958, NGC 5044, NGC 5054, NGC 5068, NGC 5077, NGC 5084, NGC 5087, NGC 5147, NGC 5170, NGC 5247, NGC 5363, NGC 5364 (Virgo)
Top ten deep-sky objects for May: M3, M51, M63, M64, M83, M87, M104, M106, NGC 4449, NGC 4565
Challenge deep-sky object for May: 3C 273 (Virgo)
All times, unless otherwise noted, are UT (subtract four hours and, when appropriate, one calendar day for EDT)
5/1 May Day, or Beltane, a cross-quarter day
5/2 Full Moon, known as the Milk or Planting Moon, occurs at 10:09
5/3 Mercury is in inferior conjunction with the Sun at 4:00
5/4 The Moon is 0.5 degree south of the first magnitude star Antares (Alpha Scorpii), with an occultation taking place in New Zealand, Tasmania, a portion of Antarctica, and southeast Africa, at 18:00
5/5 Asteroid 3 Juno is stationary today; the peak of the Eta Aquarid meteor shower (10/hour for northern hemisphere observers) occurs at 11:00; Jupiter is 6 degrees north of the Moon at 12:00
5/6 A maximum lunar libration of 8.7 degrees occurs at 21:00
5/9 Mars is its greatest heliocentric latitude south today; Mercury is at aphelion today
5/10 Last Quarter Moon occurs at 4:27; Venus is 1.7 degrees north of the center of the bright open cluster M35 in Gemini at 5:00; Neptune is 1.8 degrees north of the Moon at 8:00
5/11 Venus is its greatest heliocentric latitude north today
5/12 Uranus is 1.3 degrees south of the Moon, with an occultation taking place in most of Great Britain and eastern Greenland, at 7:00
5/13 Mars is 3 degrees south of the Moon at 1:00
5/14 A minimum lunar libration of 4.4 degrees occurs at 1:00
5/15 The Moon is at perigee, subtending 33'15" from a distance of 359,392 km, at 15:00
5/16 New Moon (lunation 1044) occurs at 19:27; Mercury is 7 degrees north of the first magnitude star Aldebaran (Alpha Tauri) at 21:00
5/18 Mercury is 3 degrees south of the Moon at 0:00
5/19 Mercury is at its greatest heliocentric latitude north today
5/20 Venus is 1.7 degrees south of the Moon at 1:00; Venus is 0.75 degree south of the Moon at 2:30; a maximum lunar libration of 8.8 degrees occurs at 3:00
5/21 The Moon is 1.4 degrees north of the bright open cluster M44 (the Beehive Cluster or Praesepe) in Cancer at 21:00
5/22 Saturn is 0.8 degree south of the Moon, with an occultation taking place in the British Isles, Europe, northeast Africa, northwest Asia, the Arctic, and northwest Canada, at 19:00
5/23 The Moon is 0.7 degree north of the first magnitude star Regulus (Alpha Leonis), with an occultation taking place in most of Asia, northeast Europe, Great Britian, Greenland, and the northeastern tip of Canada, at 16:00; First Quarter Moon occurs at 21:03
5/25 Neptune is stationary at 6:00
5/26 A minimum lunar libration of 3.7 degrees occurs at 18:00
5/27 The Moon is at apogee, subtending 29'28" from a distance of 405,460 km, at 22:00
5/28 The Moon is 1.4 degree south of the first magnitude star Spica (Alpha Virginis) at 6:00
5/30 Asteroid 4 Vesta (magnitude 5.4) is at opposition at 14:00; Venus is 4 degrees south of the first magnitude star Pollux (Beta Geminorum) at 19:00; Mercury is 1.1 degrees north of M35 at 20:00
The May 5th peak of the Eta Aquarids, a minor meteor shower produced by debris from the famous periodic comet 1P/Halley, is compromised by a waning gibbous Moon. The Eta Aquarid meteor shower favors observers in the southern hemisphere but the Orionids, another shower that is caused by Comet Halley, favors the northern hemisphere in October.
The Moon is 13.5 days old on May 1 at 0:00 UT. The Moon is at its greatest northern declination on May 18 (+28 degree) and its greatest southern declination on May 6 (-28 degrees). Ignoring Universal Time conventions, a second Full Moon, a so-called Blue Moon, takes place this month at 9:04 p.m. EDT on May 31. Times and dates for the lunar light rays predicted to occur in May are available at http://www.lunar-occultations.com/rlo/rays/rays.htm
Brightness, apparent size, illumination, distance from the Earth in astronomical units, and location data for the planets and Pluto on May 1: Mercury (-2.0 magnitude, 5.1", 100% illuminated, 1.3 a.u., Aries), Venus (-4.1 magnitude, 16.4", 68% illuminated, 1.0 a.u., Taurus), Mars (1.0 magnitude, 5.3", 91% illuminated, 1.8 a.u., Aquarius), Jupiter (-2.5 magnitude, 43.8", 100% illuminated, 4.5 a.u., Ophiuchus), Saturn (0.4 magnitude, 18.4", 100% illuminated, 9.0 a.u., Leo), Uranus (5.9 magnitude, 3.4", 100% illuminated, 20.7 a.u., Aquarius), Neptune (7.9 magnitude, 2.3", 100% illuminated, 30.2 a.u., Capricornus), and Pluto (13.9 magnitude, 0.1", 100% illuminated, 30.7 a.u., Sagittarius).
Visibility of the classical planets at mid-month for observers at 40 degrees north: Mercury can be seen in evening twilight after mid-month; Venus is dominant in the western sky after sundown and sets at midnight; Mars rises around 4:00 a.m. EDT; Jupiter clears the horizon at approximately 10:00 p.m. EDT and transits the meridian at 3:00 a.m. EDT; Saturn can be seen in the southwest after nightfall and sets at about 2:00 a.m. EDT.
Mercury's best evening apparition of the year begins this month. It may be visible again very low in the west-northwest as early as May 11 after undergoing inferior conjunction on May 3. The speedy planet lies 7 degrees north of Aldebaran on May 16 and 2.5 degrees south of the Moon the next evening. On May 23, Mercury is positioned halfway between third magnitude Zeta Tauri and second magnitude Beta Tauri as it shines at -0.3 magnitude some 7 degrees above the horizon in the west-northwest. Mercury's disk increases in size but decreases in illumination as the month progresses and by May 27 only half of the planet is sunlit. The planet's brightness drops by almost two full magnitudes during the course of the month.
Like Mercury, Venus shrinks in illumination but increases in apparent size. By the end of May, it is 5" larger but is only 55% illuminated.
Mars reaches first magnitude status this month but at 6" in apparent size is still too small for fruitful observation. It is situated low in the east-southeast at dawn. The Red Planet begins the month in Aquarius. On May 9, it heads into Pisces and then enters Cetus on May 24. By May 29, Mars is back once again in Pisces.
Jupiter rises not long after sunset by the end of May. The giant planet travels westward through Ophiuchus towards Antares in Scorpius. Jupiter begins the month eleven degrees away from the first magnitude red giant star and is eight degrees distant by the end of May. Click on http://skyandtelescope.com/observing/objects/planets/article_107_1.asp to determine transit times of the central meridian by the Great Red Spot. Data on the Galilean satellites is available at http://skytonight.com/observing/objects/javascript/3307071.html
Saturn reaches eastern quadrature during the second week of May. As a result, Saturn's shadow falls on its rings, giving the planet an enhanced three-dimensional appearance. The rings have an angular extent of 41" by 11" and the disk 18" this month. On the night of May 22, Titan (magnitude 8.8) is due east of Saturn. Rhea, Dione, and Tethys all shine at around tenth magnitude while the planet hugging Enceladus is a difficult target at nearly twelfth magnitude. Bizarre Iapetus is west of Saturn in early May and then swings to the east of the planet, decreasing in brightness from eleventh to twelfth magnitude as it does so. Titan and Iapetus are less than one arc minute apart on May 7. The position of Iapetus in relation to Saturn is as follows: May 2 (5" west), May 4 (1" east), May 8 (12" east), May 12 (22" east), May 18 (33" east), May 24 (37" east), and May 30 (34" east). For further information on Saturn's satellites, browse http://skytonight.com/observing/objects/javascript/3308506.html
Uranus and Neptune both rise prior to dawn and are therefore still poorly placed for observation. Uranus is 1.7 degrees northwest of Mars and is less than 30' to the southwest of the fourth magnitude star Phi Aquarii on May 1.
The dwarf planet Pluto is located in northwestern Sagittarius near the border with Serpens Cauda. On May 1, Pluto is 2.7 degrees north of the open cluster M23 and 6 degrees west of the bright emission nebula M17 (the Checkmark, Horseshoe, Lobster, Omega, or Swan Nebula).
Asteroid 4 Vesta reaches opposition on May 30, seventeen days before perihelion. This makes the minor solar system body almost a full magnitude brighter than normal and a fairly easy naked-eye target from a dark site until the end of June. Vesta is located to the northwest of Eta Ophiuchi and to the southeast of Zeta Ophiuchi on May 1. It passes westward through Ophiuchus during May and is situated less than two degrees south of the eighth magnitude globular cluster M107 on May 30.
Eighty binary and multiple stars for May: 1 Bootis, Struve 1782, Tau Bootis, Struve 1785, Struve 1812 (Bootes); 2 Canum Venaticorum, Struve 1624, Struve 1632, Struve 1642, Struve 1645, 7 Canum Venaticorum, Alpha Canum Venaticorum (Cor Caroli), h2639, Struve 1723, 17 Canum Venaticorum, Otto Struve 261, Struve 1730, Struve 1555, h1234, 25 Canum Venaticorum, Struve 1769, Struve 1783, h1244 (Canes Venatici); 2 Comae Berenices, Struve 1615, Otto Struve 245, Struve 1633, 12 Comae Berenices, Struve 1639, 24 Comae Berenices, Oto Struve 253, Struve 1678, 30 Comae Berenices, Struve 1684, Struve 1685, 35 Comae Berenices, Burnham 112, h220, Struve 1722, Beta Comae Berenices, Burnham 800, Otto Struve 266, Struve 1748 (Coma Berenices); h4481, h4489, Struve 1604, Delta Corvi, Burnham 28, h1218, Struve 1669 (Corvus); H N 69, h4556 (Hydra); Otto Struve 244, Struve 1600, Struve 1695, Zeta Ursae Majoris (Mizar), Struve 1770, Struve 1795, Struve 1831 (Ursa Major); Struve 1616, Struve 1627, 17 Virginis, Struve 1648, Struve 1658, Struve 1677, Struve 1682, Struve 1689, Struve 1690, 44 Virginis, Struve 1719, Theta Virginis, 54 Virginis, Struve 1738, Struve 1740, Struve 1751, 81 Virginis, Struve 1764, Struve 1775, 84 Virginis, Struve 1788 (Virgo)
Challenge binary star for May: 48 Virginis
One hundred and sixty-five deep-sky objects for May: NGC 5248 (Bootes); M3, M51, M63, M94, M106, NGC 4111, NGC 4138, NGC 4143, NGC 4151, NGC 4214, NGC 4217, NGC 4244, NGC 4346, NGC 4369, NGC 4449, NGC 4485, NGC 4490, NGC 4618, NGC 4631, NGC 4656, NGC 4868, NGC 5005, NGC 5033, NGC 5297, NGC 5353, NGC 5354, Up 1 (Canes Venatici); Mel 111, M53, M64, M85, M88, M91, M98, M99, M100, NGC 4064, NGC 4150, NGC 4203, NGC 4212, NGC 4251, NGC 4274, NGC 4278, NGC 4293, NGC 4298, NGC 4302, NGC 4314, NGC 4350, NGC 4414, NGC 4419, NGC 4448, NGC 4450, NGC 4459, NGC 4473, NGC 4474, NGC 4494, NGC 4559, NGC 4565, NGC 4651, NGC 4689, NGC 4710, NGC 4725, NGC 4874, NGC 5053 (Coma Berenices); NGC 4027, NGC 4038-9, NGC 4361 (Corvus); M68, M83, NGC 4105, NGC 4106, NGC 5061, NGC 5101, NGC 5135 (Hydra); M40, NGC 4036, NGC 4041, NGC 4051, NGC 4062, NGC 4085, NGC 4088, NGC 4096, NGC 4100, NGC 4144, NGC 4157, NGC 4605, NGC 5308, NGC 5322 (Ursa Major); M49, M58, M59, M60, M61, M84, M86, M87, M89, M90, M104, NGC 4030, NGC 4073, NGC 4168, NGC 4179, NGC 4206, NGC 4215, NGC 4216, NGC 4224, NGC 4235, NGC 4260, NGC 4261, NGC 4267, NGC 4281, NGC 4339, NGC 4343, NGC 4365, NGC 4371, NGC 4378, NGC 4380, NGC 4387, NGC 4388, NGC 4402, NGC 4429, NGC 4435, NGC 4438, NGC 4517, NGC 4526, NGC 4535, NGC 4536, NGC 4546, NGC 4550, NGC 4551, NGC 4567, NGC 4568, NGC 4570, NGC 4593, NGC 4596, NGC 4636, NGC 4638, NGC 4639, NGC 4643, NGC 4654, NGC 4666, NGC 4697, NGC 4698, NGC 4699, NGC 4753, NGC 4754, NGC 4760, NGC 4762, NGC 4866, NGC 4900, NGC 4958, NGC 5044, NGC 5054, NGC 5068, NGC 5077, NGC 5084, NGC 5087, NGC 5147, NGC 5170, NGC 5247, NGC 5363, NGC 5364 (Virgo)
Top ten deep-sky objects for May: M3, M51, M63, M64, M83, M87, M104, M106, NGC 4449, NGC 4565
Challenge deep-sky object for May: 3C 273 (Virgo)