- Messier 99 or M99, also known as NGC 4254 or St. Catherine’s Wheel, is a grand design spiral galaxy in the northern constellation Coma Berenices approximately 15,000,000 parsecs (49,000,000 light-years) from the Milky Way. It was discovered by Pierre Méchain on 17 March 1781. The discovery was then reported to Charles Messier, who included the object in the Messier Catalogue of comet-like objects. It was one of the first galaxies in which a spiral pattern was seen. This pattern was first identified by Lord Rosse in the spring of 1846.
- Coma Berenices (Wikipedia)
Coma Berenices is an ancient asterism in the northern sky, which has been defined as one of the 88 modern constellations. It is in the direction of the fourth galactic quadrant, between Leo and Boötes, and it is visible in both hemispheres. Its name means “Berenice’s Hair” in Latin and refers to Queen Berenice II of Egypt, who sacrificed her long hair as a votive offering. It was introduced to Western astronomy during the third century BC by Conon of Samos and was further corroborated as a constellation by Gerardus Mercator and Tycho Brahe. It is the only modern constellation named for a historic person.
- Messier 100 (Wikipedia)
Messier 100 (also known as NGC 4321 or the Mirror Galaxy) is a grand design intermediate spiral galaxy in the southern part of the mildly northern Coma Berenices. It is one of the brightest and largest galaxies in the Virgo Cluster and is approximately 55 million light-years from our galaxy, its diameter being 107,000 light years, and being about 60% as large. It was discovered by Pierre Méchain in 1781 and 29 days later seen again and entered by Charles Messier in his catalogue “of nebulae and star clusters”. It was one of the first spiral galaxies to be discovered, and was listed as one of fourteen spiral nebulae by Lord William Parsons of Rosse in 1850. NGC 4323 and NGC 4328 are satellite galaxies of M100; the former is connected with it by a bridge of luminous matter.
- Messier 98 (Wikipedia)
Messier 98, M98 or NGC 4192, is an intermediate spiral galaxy about 44.4 million light-years away in slightly northerly Coma Berenices, about 6° to the east of the bright star Denebola (Beta Leonis). It was discovered by French astronomer Pierre Méchain on 1781, along with nearby M99 and M100, and was catalogued by compatriot Charles Messier 29 days later in his Catalogue des Nébuleuses & des amas d’Étoiles. It has a blueshift, denoting ignoring of its fast other movement (vectors of proper motion), it is approaching at about 140 km/s.