Whirlpool Galaxy

Galaxy in the constellation Canes Venatici

The Whirlpool Galaxy, also known as Messier 51a (M51a) or NGC 5194, is an interacting grand-design spiral galaxy with a Seyfert 2 active galactic nucleus. It lies in the constellation Canes Venatici, and was the first galaxy to be classified as a spiral galaxy. It is 31 million light-years (9.5 megaparsecs/Mpc) away and 23.58 kiloparsecs (76,900 ly) in diameter.

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