M51 “Whirlpool Galaxy”

This image was taken on 2017 February, with the GSO telescope and the SBIG STF-8300. It is the result of a LRGB sequence of (10+10+11+14)x600s, for a total of about 7hr, 39m of total exposition.

The Whirlpool Galaxy, also known as Messier 51a, M51a, and NGC 5194, is an interacting grand-design spiral galaxy with a Seyfert 2 active galactic nucleus.[7][6][8] It lies in the constellation Canes Venatici, and was the first galaxy to be classified as a spiral galaxy.[9] Its distance is estimated to be 23 million light-years away from Earth.

The galaxy and its companion, NGC 5195,[10] are easily observed by amateur astronomers, and the two galaxies may be seen with binoculars.[11] The Whirlpool Galaxy has been extensively observed by professional astronomers, who study it to understand galaxy structure (particularly structure associated with the spiral arms) and galaxy interactions. (Wikipedia)