Inter-galaxy winds caught blowing away galaxy’s gas and dust

In healthy galaxies, new stars are formed from the interstellar medium (ISM), the supply of gas and dust between stars. But sometimes cosmic winds—the movement of material between galaxies—can sweep a galaxy's interstellar medium clean, putting a damper on new star production there.

A lot of the specifics about this sweep-out are unknown—specifics like how easily it happens and under what physical conditions, and whether dense, star-forming clouds can survive these winds for any length of time. However, a new study on cosmic winds has observed the process with unprecedented detail, revealing complex and fascinating subtleties never before witnessed.

The study made use the Hubble Space Telescope, which imaged a spiral galaxy 300 million light-years away. The galaxy’s orbital path within the Coma Cluster takes it close to the cluster's center, pushing it through the hot, ionized gas (or plasma) of the intracluster medium (ICM). The plasma winds from the ICM then blow against the galaxy’s ISM, creating what’s called "ram pressure"—the pressure an object experiences as it moves through a fluid.