Astronomers find early galaxy with gas outshining its stars

Using the James Webb Space Telescope, astronomers have recorded a galaxy in the young universe whose gas emits more light than its stars. This extraordinary phenomenon, as scientists highlight, provides valuable information about the early stages of the universe's development. This is the first such recorded case in history.

The James Webb Space Telescope has enabled another unusual discovery. A team from the University of Oxford spotted a unique galaxy, thanks to it, that existed around a billion years after the Big Bang. The uniqueness of this object lies in the fact that the interstellar gas in the galaxy glows brighter than its stars.

This discovery could be crucial for understanding the evolution of the universe. It represents a missing link between the first stars and well-formed galaxies.

- When I looked at the light spectrum of this galaxy, my first thought was ‘this is strange’. This is exactly what Webb was created for – to discover entirely new phenomena in the early universe. They help us understand how cosmic history began – says Dr. Alex Cameron, leading the study described in "Monthly Notices of the Royal Astronomical Society".

The research showed that observations of galaxy 9422 almost precisely match computer models of gas heated by hot, massive stars. According to Dr. Harley Katz, it looks like the stars are much hotter and more massive than those we see in the local universe. This is due to differences between the early and contemporary universe.

In the local universe, typically hot, massive stars reach temperatures from 39,000 to 50,000 degrees Celsius. However, according to the team, the stars in the discovered galaxy 9422 have temperatures exceeding 78,000 degrees Celsius. The galaxy is in a short phase, with many massive, hot stars forming in a dense gas cloud. This cloud is exceptionally bright because it is bombarded with many light photons emitted by these stars.

The existence of such gas was expected in the surroundings of the first generation of stars – the so-called Population III stars. However, scientists emphasize that this galaxy does not contain Population III stars. Webb's telescope data indicate excessive chemical complexity.

- The exotic stars of the galaxy differ from those we know – they may provide a clue to understanding the path from primordial stars to the types of galaxies we know today – says Dr. Katz.

Despite the significant discovery, many questions remain unanswered. Are the observed conditions common in galaxies from that period, or is it rather a rare phenomenon? Can they provide additional information about the earlier phases of galaxy evolution? – astronomers ask.

- This is a very exciting time when we can use the Webb Telescope to study a previously inaccessible period in the history of the Universe – emphasizes Dr. Cameron. - We are just beginning to make discoveries and gain a broader understanding – he adds.