Luca Cortese

A galaxy cluster is like a busy intersection where galaxy-cars race through a headwind of hot gas. This wind, called ram pressure, strips galaxies of their cold gas — the fuel for star formation. Astronomers from the SAMI survey traced how this happens in hundreds of galaxies across eight nearby clusters.

At night, a telescope looks at a star but sees it as a quivering blob. Earth's atmosphere is constantly rippling, and light passing through it bends like a flashlight beam through water.