M 102 (also known as NGC 5866) lies
approximately 44 million light years away in the constallation of
Draco, the dragon. It is the largest member of a small cluster of
galaxies - the M 102 group. It spans 35,000 light years, one-third
that of the Milky Way.
M 102 was discovered by Peirre Mechain
in 1781. Charles Messier included it in his catalog without confirming
its coordinates. This raised the question of whether this object
was a duplicate of M 101.
M 102 is categorized as a lenticular
galaxy. These are an intermediate between an elliptical and spiral
gaxay. They have a disc with a central bulge but no spiral arms.