Many constellations were not included in the 48 constellations listed by the Greek astronomer Ptolemy due to several major and minor reasons behind it. However, there is one constellation that was used to be an asterism in the constellation before it was defined as one of the 88 constellations. It was the constellation Coma Berenices. Also known as Berenice’s Hair, it is a constellation in the northern hemisphere. Initially, this constellation was a part of the Leo constellation which was categorized by Ptolemy. However, Ptolemy did not consider it as a constellation until the 16th century, but it was Danish the nobleman and Tycho Brahe an astronomer who promoted Coma Berenice to the status of constellation. The constellation is associated with the story of Queen Berenice II of Egypt and belongs to the Ursa Major family of constellations. It is best visible in the month of May at 9 pm. Let us discuss further about this constellation.
Some of the major stars comprising this constellation are:
- Diadem– a Comea Bernices or Alpha Comae Berenices: It is the second brightest star of this constellation. The name Diadem is derived from a Greek word meaning ‘band or fillet’. The traditional name of Alpha Comae Bernices is Al Zafirah, an Arabic word for ‘the braid’. Its apparent magnitude is about 4.32 and it lies approximately 63 light years distant.
- β Comae Berenices or Beta Comae Berenices: It is the brightest star of this constellation. Similar to the sun, it is slightly larger and brighter and is a main sequence dwarf star. Its magnitude is 4.26 and it is approximately 29.78 light years distant from the solar system.
- Y Comae Berenices or Gamma Comae Berenices: It is a giant star with an apparent magnitude of about 4.350. It lies approximately 170 light years distant.
- FK Comae Berenices: It is a variable star. It is a prototype for an entire class of variable stars. As they have large cold spots on their rotating surfaces, these stars are believed to be variable stars. Its magnitude varies between 8.14 and 8.33 and it lies approximately 800 light years away from the earth.
Coma Berenices has numerous deep sky objects and Messier objects. The notable ones include:
- The Black Eye Galaxy or Messier 64 (M64, NGC 4826): It is a spiral galaxy which is also called the Sleeping Beauty Galaxy. It is also nicknamed the Evil Eye Galaxy due to a dark band of dust in front of it and a bright nucleus. A popular object among the amateur astronomers, it has an apparent magnitude of 9.36 and it lies approximately 24 million light years away from the earth.
- The Needle Galaxy or NGC 4565: This galaxy is one of the most famous edge–spiral galaxies in the sky. Discovered by Sir William Herschel in 1785, it is exactly above the North Galactic Pole. Its apparent magnitude is about 10.42 and is visible from a small telescope. It lies approximately 42.7 light years distant.
- Coma Star Cluster or Melotte111: This is a small cluster consisting of nearly about 40 bright stars with a magnitude between 5 and 10. The star spans over 7.5 degrees and is believed to be around 450 million years old. It lies about 280 light years from the earth.
- Coma Cluster of galaxies: This galaxy contains about 1,000 large galaxies and 30,000 smaller galaxies of which, a majority of them are brighter than 19.0. Though the galaxy lies to the north of the Virgo Cluster, it appears significantly remote, between 230 and 300 million light years from the solar system.
- Virgo Cluster of galaxies: This constellation, at times is also called the Coma–Virgo Cluster as it contains the northern part of the Virgo Cluster of Galaxies. Galaxies like Messier 100, Messier 85, Messier 99, Messier 88 and messier 91 falls in this cluster. It is located roughly 60 million light years away from the earth.
Some of the Messier objects are:
- Messier 53 (M53, NGC 5024): It is a round globular cluster with a very bright centre. It is also the brightest Messier. It was discovered by Johann Elert Bode in 1775. Its apparent magnitude is about 8.33 and it is located approximately 58,000 light years away from the earth and about 60,000 light years from the Galactic Centre.
- Messier 100 (M100, NGC 4321): It is a grand design galaxy with a shinning core, two main spiral arms and a few less brighter ones along with the dust lanes.
- Messier 85 (M85, NGC 4382): It is a lenticular galaxy which interacts with two smaller neighbours.
- Messier 99 (M99, NGC 4254): It is an unbarred spiral galaxy which is believed to have been distorted by the dark galaxy VIRGOHI21.
- Messier 88 (M88, NGC 4501): Another spiral galaxy, it produces narrow spectral line emissions from highly ionized gas in its nucleus. This galaxy has multiple spiral arms with a huge black hole in its centre.
- Messier 91 (M91, NGC 4548): It is another spiral galaxy also belonging to the Virgo Cluster.
- Messier 98 (M98, NGC 4192): It is an intermediary and stretched out spiral galaxy with huge faint spiral arms and a small core. It is located within the Virgo Cluster.
- NGC 5889 or Caldwell 35: It is located in the Coma Cluster and is a supergiant elliptical galaxy.
- NGC 4147: This is a small faint globular cluster which, when seen through a telescopes, looks like a round bright cluster without a distinct bright core.
Seen at latitudes between +90° and -70°, it lies in the third quadrant of the northern hemisphere.
This constellation occupies an area of 386 square degrees, making it the 42nd constellation of the sky. The primary star of Coma Berenices is 610 light years away from the earth and Beta Coma Berenices is 30 light years away from the earth. Therefore, it can be said that Coma Berenices is 610 light years away from the earth.
Coma Berenice is associated with a mythological story. It represents Queen Berenice II of Egypt, who was also the wife of Ptolemy III Euergetes. When Euergetes left for a dangerous mission, his wife swore to goddess Aphrodite that if her husband returns safely, she would cut her blonde hair. Euergetes returned safely and as sworn the queen cut her hair and placed it in Aphrodite’s temple. The next morning the hair had disappeared, this was considered as a sign of the goddess being pleased. The king’s astronomer pointed out to a cluster of stars in the sky calling it Berenice’s Hair.
Bootes, Canes Venatici, Leo, Ursa Major and Virgo are the constellations that neighbour Coma Berenices.
