The James Webb Space Telescope (JWST) has caused quite a stir because it got up and running last summer, revealing a slew of contenders for the title of “oldest galaxy we have ever seen.”
There’s still no clear verdict on the winner of that contest, but JWST helped astronomers crown a unique champion last month. They only confirmed the faintest galaxy yet seen within the early universe, a result published within the journal Nature.
“Before the Webb telescope switched on, only a 12 months ago, we couldn’t even dream of confirming such a faint galaxy,” UCLA astronomer Tommaso Treu, a co-author on the brand new work, said in a press release.
Related: James Webb Space Telescope (JWST) — A whole guide
This galaxy, often called JD1, is an element of the primary generation of galaxies to pop up in our universe‘s 13.8-billion-year history. It’s about 13.3 billion light-years away from us, meaning we’re observing it because it looked when the universe was only a number of hundred million years old — a meager 4% of its current age. This early era of the universe is often called the “epoch of reionization,” the time when the primary stars formed and ushered the universe out of darkness.
Astronomers are still attempting to work out exactly what the primary galaxies looked like, and the way they were in a position to light up the universe to create what we see today. A lot of the infant galaxies JWST has spotted are brilliant, but they’re considered outliers. As a substitute, astronomers suspect that fainter, smaller galaxies like JD1 did a lot of the heavy lifting during reionization.
“Ultra-faint galaxies corresponding to JD1, alternatively, are much more quite a few, which is why we consider they’re more representative of the galaxies that conducted the reionization process,” said study lead creator Guido Roberts-Borsani, an astronomer at UCLA, in the identical press release.
JWST’s powerful infrared instruments were only a part of the explanation astronomers were in a position to observe JD1. In addition they used a method called gravitational lensing, during which light from a distant object is bent by the gravity of something huge within the foreground, like a cluster of galaxies. This acts like a magnifying glass, making faraway objects appear greater and brighter — and, within the case of JD1, possible to identify.
“The mix of JWST and the magnifying power of gravitational lensing is a revolution,” said Treu. “We’re rewriting the book on how galaxies formed and evolved within the immediate aftermath of the Big Bang.”
