Ultramassive stars reveal cosmic monsters in ancient star clusters.
The James Webb Space Telescope has detected chemical traces suggesting the presence of supermassive stars in globular clusters, providing the first observational evidence for the enrichment theory. These stars are believed to have "polluted" the original gas cloud as globular clusters formed, leading to uneven chemical enrichment in infant stars. The team used the infrared vision of JWST to catch globular clusters earlier in their existence and found that several globular clusters are being born in GN-z11, a distant galaxy, and still host active supermassive stars. The results strengthen the model of supermassive star enrichment suggested by the team to explain the strange compositions of globular clusters.