A team of astronomers found that in typical galaxies, pressure from ionized gas generated by newly formed stars drives the expansion of star-forming regions. However, whether these regions continue to grow or stall depends strongly on their surrounding environment.

Astronomers have used U.S. National Science Foundation National Radio Astronomy Observatory (NSF NRAO) radio telescopes in Chile and New Mexico to peer through cosmic smoke and haze, building one of the clearest pictures yet of how giant clusters of young stars are born in the hearts of nearby galaxies.