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A Puzzle of Galactic Evolution is Solved – Massive Gas Clouds Seed the Galaxy with the Stuff of Stars


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Massive clouds of gas, discovered long ago but only recently identified as being within the margins of the Milky Way, play a key role in the galaxy's ability to churn out new stars by raining gas onto the plane of the galaxy. Researchers have chipped away at a three-decade-old mystery about the nature and role of those massive gas clouds, called high-velocity clouds. In the process, they've discovered a mechanism by which the galaxy is seeded with the stuff of stars and solved a long-standing question of galactic evolution.

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