Messier 100 is a grand-design spiral galaxy in the constellation in Coma Berenices. It is located 55 million light-years away from us and is one of the brightest galaxies in the Virgo Cluster, and one of the first spiral galaxies discovered. M100 shines at magnitude 9.3 and subtends an apparent size of 7.5 x 6.1 arcminutes. At its estimated distance, it would have a diameter of 120,000 light-years in space. NGC 4323, just to the top left of M100, is believed to be a satellite galaxy to M100. NGC 4328 is to the left and IC 783A is in the lower right corner. Pierre M矇chain discovered M100 in 1781.