A Tale of Tails: Stripping and Star Birth in Jellyfish Galaxies
Astronomers studied four galaxies in the cluster MACS J0138.0-2155, three of which are jellyfish galaxies with long gas tails caused by ram-pressure stripping. J1 and J2 show quenched centers but star formation in their tails, while J3 is earlier in its transformation with strong central star formation. These results highlight how cluster environments strip gas, quench galaxies, and trigger new stars in their tails.
Do Most Stars Form in Clusters? A New Look at Our Galaxy’s Star Birthplaces
Quintana and collaborators used new Gaia data to show that most stars in the Milky Way likely form in compact clusters. Their calculations suggest that at least half, and probably over 80%, of stars are born this way, much higher than past estimates. This supports the clustered star formation model, though many clusters dissolve quickly, leaving stars spread across the Galaxy.