A few months ago, the Hubble Space Telescope made history by spotting Earendel, the furthest known single star or binary star system, in an extremely gravitationally lensed image of a distant galaxy. Its light comes from just 900 million years after the Big Bang, making it the most distant known star yet. Now, the team has just shared JWST's image of it.
If you're looking at that bright spiky star and thinking wow, sorry, that's not Earendel.
In the image, we see a bright foreground star (located in the Milky Way) with the now characteristic six spikes of JWST images. This is due to the physical structure of the telescope creating diffraction spikes. The brighter the light the more prominent the feature. Just underneath the star is the massive galaxy that causes the gravitational lens, warping space-time and majorly magnifying the distant galaxy that hosts Earendel.
Our star is to be found in a thin red arc (follow the southeastern spike from the foreground star). Along the so-called Sunrise Arc, a small red dot is visible. That is Earendel. A star that now no longer exists, but whose host galaxy now sits 28 billion light-years from us.
“It’s the most distant star that has been discovered thus far, which is very exciting just for the superlative of it,” Brian Welch, a member of the discovery team, previously told IFLScience. “It’s also within the first billion years of the Universe so at a time when we know that galaxies look very different and we expect that stars would look very different as well.”
The star was named "Earendel" as it means meaning "Morning Star" or "Rising Star" in the Old English poem of Crist. If it sounds like it could be out of a Tolkien story, you wouldn’t be wrong. The word’s root is Proto-Germanic and the British fantasy author chose Eärendil for the name of the half-elven mariner that carried the light of one of the Silmaril across the sky.
The star is estimated to weigh between 50 and 100 times our Sun but JWST observations will refine the estimations. The observations were part of the Cosmic Spring program on JWST that focuses on galaxies in the early universe magnified by gravitational lensing.