The James Webb Space Telescope Might Have Spotted the Most Distant Galaxy Ever Seen
Scientists think the light detected by the telescope is from just 300 million years after the Big Bang
The James Webb Space Telescope launched into orbit seven months ago and is now peering deep into space. Last week, two independent teams of scientists announced that the telescope might have spotted a galaxy from 13.5 billion years ago, just 300 million years after the Big Bang, reports New Scientist’s Jonathan O’Callaghan. If the findings are confirmed, the galaxy would be the most distant ever detected.
Webb’s ultra-powerful instruments can detect light that has traveled from distant parts of the universe. Since this light had such a long journey, it’s very old light, and scientists want to use it to learn more about the early days of the universe.
“We have, for all of human history, been bathed in light reaching us from such distant galaxies, born when the universe was just a few hundred million years old,” Chris Lintott, an astronomer at Oxford University who studies galaxy formation and was not involved in the new research, tells The Atlantic’s Marina Koren. “But only now have we built something capable of capturing it.”
The findings have not been published yet, so they still need to undergo peer review, notes The Atlantic. Plus, the researchers need more data to confirm the results. The telescope’s instruments are also still being calibrated, per Vice’s Becky Ferreira, which could influence the dating process.
The researchers also found a second galaxy that might be from a similar time as the previous most distant galaxy, reports New Scientist. Compared to our modern galaxy, these early galaxies are tiny–while the Milky Way is now around 100,000 light years across, the younger, newly discovered galaxies are a mere 2,000 light years in diameter, according to Vice.
But the galaxies are still larger than scientists would expect such young galaxies to be, weighing in at roughly a billion times heavier than our sun, per New Scientist. This suggests that stars might form faster in the early universe than previously thought.
“The most surprising thing is how massive and bright these galaxies have gotten so fast–billion solar galaxies, so early in the Universe, are expected by several leading models of galaxy formations to be rather rare!” Rohan Naidu, a graduate student in astronomy at Harvard University leading one of the studies, tells Vice. “But our search is showing, perhaps not…”
Scientists can figure out how old light is in part by looking at how close together the peaks of its waves are. Since the universe has been expanding since the Big Bang, light gets stretched out into redder wavelengths that Webb’s infrared detectors can pick up, per The Atlantic. To confirm that some of the light is from 13.5 billion years ago, the scientists now have to determine its chemical makeup.
With Webb in the sky now, discoveries of ancient galaxies should occur much more frequently, per New Scientist. According to The Atlantic, the telescope’s full detecting power hasn’t even been unleashed yet, and it has only been pointed at a narrow sliver of space.
CNET’s Jackson Ryan reported on Monday that additional preprint papers have already been posted on the preprint server arXiv with candidates for galaxies even farther away than the one detected last week.