M 37 is the largest and brightest of 3 bright open clusters in
Auriga (the others are M 36 and M 38). M 37 isthe oldest of the
3 major Auriga clusters, as indicated by the presence of several
older, red-giant stars. The estimated age of this cluster is
300 million years.

Image data:
Camera: Canon 350 XT (modified)
Exposure: ISO 800, 2 minutes x 21
Telescope: 10" Schmidt-Newtonian, Baader MPCC