Look low in the west soon after sunset on Saturday, May 27th, and you may be able to see a very thin crescent Moon, less than 24 hours old. Best seen form North America.
North American Nebula this is an enormous and vivid cloud of gas and dust which has striking resemblance to North America, . Due to its large size (four degrees across, eight times the angular size of the Moon), the nebula ("NGC7000") must be viewed with low power instruments such as richest field telescopes or binoculars. Located in Cygnus the Swan, it rises in the east in the early evening on this date and becomes an easy object by 11:00 PM. For a relatively faint patch such as this a dark moonless sky is going to be necessary. First look for it with the naked eye. If you can't find it that way, try sweeping across the area with your binoculars. Behind the nebula lies the part of the Milky Way. Photographs will show a million dancing fiery lights all splashed wildly across the ebony sky. Deneb is thought to be the illuminating star, at about 70 light years away. The cloud is itself about 45 light years across.
The Summer Triangle -- Vega, Deneb, and Altair -- holds the central position, high in the south. The scorpion sits low to the south and slightly west. Directly to the arachnid's east is Sagittarius, the Archer, and between the two lies the direction toward the Milky Way galaxy's centre. The ribbon of soft light that delineates our galaxy flows up from the south, through the Triangle, and then cascades toward the northern horizon.
Bootes, the Herdsman As May heads into June, the precession of Greek character continues across the evening skies. This evening you will likely see Bootes, the Herdsman, rising high in the heavens. Bootes is believed to have been Arcas the illicit son of Zeus and Callisto, the daughter of Arcadia. Callisto was the favourite hunting partner of the goddess of hunting, Artemis. Zeus wanted Callisto and succeeded by assuming the appearance of Artemis one day. When it became clear to the real Artemis what had happened, she banished her friend from her company. After Callisto gave birth to her son, Arcas, the wife of Zeus became angry at her husband's indiscretions. Cursing her, she changed her rival into a bear and condemned her to wander the forest for years to come. Years later Arcas himself became an accomplished hunter and stumbled across this bear in the woods. At that point, Zeus stepped in and sent the both of them into the heavens where Callisto was turned into Ursa Major and her son Arcas, Bootes. In another legend Bootes was identified as Icarus, the inventor of wine. One day he gave some wine to a few clueless shepherds. Mistaking their drunken state for being poisoned they, killed him. Maera, his dog ran home and returned with Erigone, the daughter of Icarius who upon seeing her dead father committed suicide along with the dog. Taking pity on them, Zeus immortalized them in the heavens for all eternity. Maera became Canis Minor, Erigone is now seen as Virgo, and Icarius of course is Bootes. The constellation is best known for housing Arcturus, the fourth brightest star in the sky .
Coma Berenices Rising in the eastern skies about mid-evening is the faint constellation, Coma Berenices, "Berenices' Hair", . Undistinguished as it seems, this constellation has one significant feather in its cap : this is where the North Galactic Pole (NGP) is located in between stars Beta and Gamma. The galaxy like everything else in the Universe rotates around on an axis. Where the Earth spins every 24 hours, our galaxy takes about 20 million years for each rotation and the NGP is where the North Pole of the galaxy is aimed. The southern Galactic Pole is located in Sculptor. Since you are looking away from the galaxy you will see fewer bright stars than toward the body the Milky Way. But now you have a clear shot into extra galactic space revealing all many more galaxies which would otherwise be hidden by our own. While Coma Berenices is one of the more modern constellations (being created in 1551), the grouping was mentioned on occasion by the ancients. Frequently referred to both as the "hair" of either Ariadne or Queen Berenice of Egypt. Unlike most constellations this is one of the few that refers to a real person. Berenice married her brother, Ptolemy III (as was Egyptian royal tradition) in the third century BC. A few days after her marriage Ptolemy went off to war. She promised him that if he were to return safely she would cut off her hair. He did, and so she did, placing it in the temple as a gift to the gods. The next day her hair mysteriously was gone, gone to the stars according to the court mathematician. While dim in stars, Coma Berenices is a very fertile playground for astronomers, containing about half of the famous Coma-Virgo galactic cluster. So it has many fine galaxies well within the grasp of amateur telescopes.
Notable Messier objects
M13— in the constellation Hercules, is one of the largest of over 100 globular clusters in our Galaxy. Located about 25,000 light-years away, it contains about half a million stars packed into a space only a few tens of light years in diameter. Globular clusters contain some of the oldest stars in the Universe. M56—Also in the constellation of Lyra we find our first globular cluster of the night. In a telescope look for a small round ball of light, slightly brighter in the centre. This is a difficult binocular object appearing as a small fuzzy patch. M27—Also known as the Dumbbell nebula, the largest planetary nebula in the Messier Catalogue, M27 lies in the constellation Vulpecula. Fairly easy to see in binoculars as a small hazy patch. In small to medium scopes it appears as a rectangular patch of light. In large scopes it may even appear round in shape with a bright rectangular, or dumbbell shaped core.
Venus at magnitude -4.1, spends most of the month in Pisces, except for the 9th to 12th when it crosses through one corner of Cetus, the Whale. The planet is high above the south-eastern horizon in the morning skies on the 1st, but during this month it will move towards the Sun and hence into the dawn skies. The waning crescent Moon is above the planet on the morning of the 24th. Best seen from 4.5h - 4.9h. (on May 2nd, RA=23h54m48s Dec= -1°57.6' (J2000) Distance=0.970AU Elongation= 43° Phase=66% Diameter=17.2")
The Moon is at apogee on the 7th, 7:46.3 UT ; and at perigee on the 22nd, 16:24.9 UT. On the 14th, Emersion of 2 Sco, SAO 183896 (Multiple star system), 4.5mag PA=5.5, h=12.3 (dark limb). On the 18th, Emersion of Terebellum, 60 Sgr, SAO 188778 (Close double star), 4.8mag PA=295.9, h=4.3 (dark limb). First Quarter on the 5th, 6:13.0 UT Full Moon on the 13th 7:51.1 UT Last Quarter, on the 20th, 10:20.5 UT New Moon on the 27th 6:25.6 UT
Mars at magnitude 1.5 moves across the constellation Gemini, the Twins, and into Cancer, the Crab on the 31st. On the 1st and 30th the crescent Moon will be near the planet. Mars will be extremely close to Saturn next month. Best seen from 21.0h - 1.5h (on May 1st, RA= 6h45m05s Dec=+24°36.7' (J2000) Distance=1.924AU Elongation= 59° Phase=92% Diameter=4.9".)
Jupiter at magnitude -2.5, is at its brightest magnitude of the year on the 4th at 15:36 UT while in the constellation Libra, the Scales. This increase in brightness occurs due to the differences in orbital speed of the Earth and Jupiter that bring the planets closer every 13 months or so - astronomically called opposition. Because of this Jupiter is visible for the entire night, moving from the south-east during the evening to the west at dawn. With binoculars you can easily see the four main moons of Jupiter. In increasing distance from the planet these are Io, Europa, Ganymede and Callisto. The Moon (unfortunately rather bright as it's nearly full) sits off to the right of Jupiter on the 11th. Best seen from 21.1h - 4.8h (on May 2nd, RA=14h48m21s Dec=-14°48.2' (J2000) Distance=4.414AU Elongation=178°)
Saturn at magnitude 0.3 sits above and to the left of Mars in the constellation of Cancer the Crab. Saturn on the last few days of the month enters the starfield of M44 (Messier catalogue object 44) known as the Beehive or Praesepe open star cluster. Worth a look with binoculars from 27th onwards. The view of the month must be Saturn in the Beehive with the crescent Moon above on the 31st. Best seen from 21.0h - 2.6h (on May 1st, RA= 8h29m46s Dec=+19°45.9' (J2000) Distance=9.183AU Elongation= 84°)