Astronomers using the James Webb Space Telescope have discovered the most distant “jellyfish galaxy” ever seen, offering a rare glimpse into how galaxies changed billions of years ago.
The newly spotted galaxy lies so far away that its light has taken about 8.5 billion years to reach Earth, meaning scientists are seeing it as it existed when the universe was much younger.
Jellyfish galaxies get their unusual name from their appearance. As they race through crowded galaxy clusters, hot gas surrounding the cluster acts like a powerful wind.
This wind pushes gas out of the galaxy, stretching it into long, trailing streams that resemble tentacles.
The process, known as ram-pressure stripping, can dramatically reshape a galaxy by removing the material needed to form new stars.
The discovery was made by a team from the University of Waterloo while studying a well-known patch of sky called the COSMOS field.
This region has been observed by many telescopes because it offers a clear view into deep space with little interference from dust or stars in our own Milky Way.
While examining the James Webb data, the researchers noticed a distant galaxy with the distinctive features of a jellyfish galaxy that had not been documented before.
Despite its dramatic tails, the galaxy still has a normal-looking disk at its center. The trailing streams contain bright blue clumps, which are very young stars.
This suggests that star formation is happening within the stripped gas outside the galaxy itself, a hallmark of jellyfish galaxies.
What makes this discovery especially important is how early in cosmic history the galaxy exists.
Scientists had believed that 8.5 billion years ago, galaxy clusters were still forming and might not yet have been dense or violent enough to strip gas so aggressively from galaxies.
The new finding suggests that some clusters were already harsh environments capable of reshaping galaxies much earlier than expected.
The observation also hints at how many galaxies in clusters may have lost their gas long ago and stopped forming stars, becoming what astronomers call “dead” galaxies.
Understanding when and how this transformation happened is key to explaining why galaxy clusters today contain so many inactive galaxies.
Researchers say the discovery challenges previous ideas about the early universe and shows how powerful the James Webb Space Telescope is for studying distant objects. By observing galaxies at such great distances, scientists can look back in time and piece together how cosmic structures evolved.
The team hopes to obtain more observing time with the telescope to study the galaxy in greater detail. Additional data could reveal more about the conditions inside early galaxy clusters and how common these dramatic transformations were.
This distant jellyfish galaxy serves as a reminder that the universe was already a dynamic and sometimes violent place billions of years ago. Each new discovery helps astronomers better understand how the galaxies we see today came to be.
