Chart showing the constellation.
This faint constellation represents the flowing lock of Queen Berenice of Egypt, who cut off her hair in gratitude to the gods for the safe return of her husband Ptolemy Euergetes from battle. It was known to the ancients, but was included either with Leo or Virgo. It was the Danish astronomer Tyco Brahe who catalogued it separately as a constellation in 1602.
The main part of the Queen's severed tresses is represented by a scattering of about 30 stars, known as the Coma Star Cluster. This is best seen in binoculars. The brightest members of the cluster (5th and 6th magnitude) form a noticeable arrowhead shape. These stars in the cluster are about 250 light years away.
The constellation also contains a cluster of galaxies but these are too faint for small telescopes. Some brighter members of the Virgo cluster of galaxies marked are bright enough for reasonable sized amateur telescopes.
On a clear dark night way from city lights when the Moon is out of the sky, Coma Berenices may be picked out looking like a faint detached portion of the Milky Way, between Leo and Boötes. Look between the bright stars Regulus and Arcturus.
α Comae Berenicis (Diadem) is a white magnitude 4.3 star 47 light years away.
β Com is a magnitude 4.3 yellow star 30 years away.
γ Com is a magnitude 4.4 orange star 170 light years away
24 Com is a beautiful coloured double star for small telescopes, consisting of an orange giant star of magnitude 5.2 and a magnitude 6.7 blue-white companion. This companion is in addition a spectroscopic binary with a period of 7.34 days.
M 53 is a beautiful rich and compact globular cluster about 65,000 light years away, visible in small telescopes as a rounded hazy patch.
M 64 is a famous spiral galaxy known as the Black Eye Galaxy because of a dark cloud of dust distinctly concave shaped bordering the nucleus. Apertures above 150 mm are needed to see the dark dust lane, smaller apertures can only find this a faint fuzzy patch.
M 85 is a conspicuous elliptical galaxy 65 million light years away. Small telescopes show a bright star-like centre.
M 88 is a fine spiral galaxy seen nearly edge-on, so that it appears elliptical. It is also about 65 million light years away.
M 100 is a regular face-on spiral galaxy appearing as a large diffuse luminous haze, rising to a small bright nucleus. It is one of the brightest spirals in the Virgo Cluster.
NGC 4565 is a remarkable edge-on spiral galaxy. Instruments of 200 mm or more aperture show it as a cigar-shaped body split by a dark dust lane, with a noticeable central bulge and a star-like core. It lies about 20 million light years away.
Visibility
Coma Berenices rises to be between 15° and 30° above the northern horizon as seen from the south of New Zealand, latitude 46° south. It gets about 10° higher as seen from the latitude of Auckland. α Com is at its highest about 9 pm NZST at the beginning of June.
The constellation remains visible in the early evening sky until mid August when it will be very low, to the northwest, as the sky becomes dark following evening twilight and will set soon after.