Messier 100

Messier 100 (also known as NGC 4321 ) is a 9.3 like bright spiral galaxy with a surface area of 7.6 '× 6.2 ' in the constellation Coma Berenices.

M 100 is a member of the extreme northern part of the Virgo galaxy cluster. Like almost all spiral galaxies M 100 is located so far from the densely populated center of the galaxy cluster removed. Among the spiral galaxies of this cluster M 100 is the brightest. She is from the Hubble type Sc, and their galactic plane is inclined by more than 60 degrees to the line of sight, so that we have a very good view of the galactic disk. This M 100 relate to an ideal study object for all questions that spiral galaxies in the Virgo Cluster. M 100 was therefore resolved as a first spiral galaxy of this cluster into individual stars in particular, H0 Key Project to measure the Hubble constant H0 with the Hubble Space Telescope. In this study Cepheids were identified by their period-luminosity relation, the distance of M could be determined 100 to 55 million light years. This distance is probably a little less than the distance of the cluster center.

Within Messier 100, is the supernova SN 1979C, which is exceptional because of their still ongoing X-rays.

M 100 is also the main galaxy of a small subgroup within the Virgo Cluster, to continue to primarily include dwarf galaxies.

Ultraviolet absorption by GALEX

Discovery

The galaxy NGC 4321 was discovered on 15 March 1781 by the French astronomer Pierre Méchain.