Messier 51 - The Whirlpool Galaxy
Messier 51's close interaction with NGC 5195, the small, yellow galaxy at the tip of one of the arms makes M51 a popular target for astronomers. Imaging from the Hubble Telescope shows that NGC 5195 is passing behind M51and has been moving past the Whirlpool for hundreds of millions of years.
Discovered by Charles Messier in 1773, M51 is located 31 million light-years from Earth in the constellation Canes Venatici.
