Whirlpool Galaxy - Wikipedia, the free encyclopedia

The Whirlpool Galaxy (also known as Messier 51a, M51a, or NGC 5194) is an interacting[6] grand-design[7] spiral galaxy with a Seyfert 2 active galactic nucleus[8] in the constellation Canes Venatici. Recently it was estimated to be 23 ± 4 million light-ye

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