M100 is a grand spiral galaxy in Coma Berenices and is a member of the Virgo galaxy cluster. It supports a very high rate of star formation and is classified as a starburst galaxy. It has two neighboring small galaxies, seen to the right and below M100. The lower one, NGC 4323, is connected to M100 by a faint bridge of luminous material. The image was taken with a 12.5" PlaneWave telescope and a QSI-640ws camera at f/8 under very good seeing conditions. Total integration was 9 hours using luminance and red, green, blue filters from a dark-sky site near Anza, CA.
-- Bruce Waddington