25 Oct '16, 2pm
Don't panic, but a massive hydrogen cloud is going to crash into the Milky Way
Essentially, the Smith Cloud is getting whipped back into the outer edge of the Milky Way. It could be 30 millions years before the giant cloud of hydrogen gas meets the edge of our galaxy, but in the meantime, NASA scientists are working to learn more about its composition, which would offer new clues about its origin. So far, they’ve learned the cloud is as rich in sulfur as the Milky Way’s outer disk, a region about 40,000 light-years from the galaxy’s center. That discovery indicates Smith Cloud was enriched by star material, leading scientists to believe it may have been hurled out of our galaxy at some point, rather than having its origins in a separate failed galaxy.