Nearby Galaxy M33

This is a composite image of the galaxy M33 in the constellation Triangulum.  It is a collection of 40 billion stars about 3 million light years away.  M33 is one of three large galaxies in our local group (including also the Andromeda Galaxy and the Milkway Galaxy).  The Barber Research Observatory is monitoring a number of massive stars in M33 as part of a project sponsored by the National Science Foundation (NSP) under grant number 1108890.

The image is a composite of nine separate images taken in three different filters (Blue = Johnson B, Green = Johnson V, Red = Cousins R).  Each image was a ten minute exposure with the 20-inch telescope and the U42 CCD camera.