Hubble Sees Our Galaxy Sucking Up a Mysterious Amount of Gas

Artist’s concept of gas clouds flowing in and out and how Hubble observes it
Illustration: NASA, ESA, and D Player

The Milky Way seems to be gobbling up a mysterious amount of gas—more than it spits back out, according to a new paper.

Our galaxy maintains a level of “stuff” through a feedback process: It eats up gas from the surrounding environment to form stars, and then it spits the gas back out via supernovas and stellar winds. Using data from the Hubble Space Telescope, a team of astronomers calculated that more mass appears to be flowing in than is flowing out—an unexpected result, according to a Hubble press release.