Why some galaxies stop creating stars

ESO 137-001 is a perfect example of a spiral galaxy zipping through a crammed cluster of galaxies. Gas is being pulled from its disc in a process called ram pressure stripping. The galaxy appears to be losing gas as it plunges through the Norma galaxy cluster. Image credit: NASA, ESA, and the Hubble Heritage Team.
Scientists may finally have an explanation for why some galaxies stop creating stars after a team of astrophysicists painstakingly analysed around 70,000 galaxies to understand the fo