Andromeda And The Milky Way Might Collide Sooner Than We Think
The merger of the Milky Way and Andromeda galaxy won’t happen for another 4 billion years, but the recent discovery of a massive halo of hot gas around Andromeda may mean our galaxies are already touching. Andromeda’s halo is gargantuan. Extending for at least 2 million light years, if we could see in our night…
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Bob King - Universe Today