NGC 4145 is around 44 million light years
away and is part of the Ursa Major cluster of galaxies. This
cluster contains many bright spirals for which NGC 4145 is a
member. However this galaxy is considered relatively "anemic"
due to the fact that unlike most spiral galaxies it does not
have alot of star formation taking place. While the spiral arms
of this galaxy are punctuated by some activity, the rest of the
galaxy is quite quiet. Indeed astronomers suggest that a galaxy
like this will soon (in galactic terms) lose the impetus to form
stars and settle down to become a lenticular galaxy.
Interestingly this galaxy is interacting with another (NGC
4151). This may help maintain the star formation in NGC 4145. In
fact close inspection of the nucleus of NGC 4145 seems to
indicate that the tug of NGC 4151 has displaced it from its
position in the center of NGC 4145.