Galaxies die earlier than expected

For a long time, scientists thought that only actively star-forming galaxies should be observed in the very early Universe. The James Webb space telescope now reveals that galaxies stopped forming stars earlier than expected. A recent discovery deepens the tension between theoretical models of cosmic evolution and actual observations. Among hundreds of spectra obtained with the Webb program RUBIES, the team has found a record-breaking galaxy that had already stopped forming stars during an epoch where galaxies are normally growing very rapidly.

Galaxies die earlier than expected
For a long time, scientists thought that only actively star-forming galaxies should be observed in the very early Universe. The James Webb space telescope now reveals that galaxies stopped forming stars earlier than expected. A recent discovery deepens the tension between theoretical models of cosmic evolution and actual observations. Among hundreds of spectra obtained with the Webb program RUBIES, the team has found a record-breaking galaxy that had already stopped forming stars during an epoch where galaxies are normally growing very rapidly.