M51a With NGC 5195

Taken by Walter Gebhart. 2-hour acquisition M51, the Whirlpool Galaxy, one of the most famous spiral galaxies in the sky. Located about 31 million light-years away in the constellation Canes Venatici, it consists of the large spiral galaxy M51a interacting gravitationally with its smaller companion NGC 5195. This cosmic encounter has enhanced M51’s spectacular spiral arms and triggered widespread star formation, creating bright pink hydrogen regions (more brownish in my image) and clusters of young stars. Discovered by Charles Messier in 1773, M51 was the first galaxy where spiral structure was clearly identified. It spans roughly 76,000 light-years and is visible with modest amateur telescopes. If you look carefully and if you have a big screen there are a few more galaxies visible far, far behind the Whirlpool. The most obvious one to the upper right is an edge on spiral galaxy about 400 – 500 million light years away.