James Webb Recasts 10-Billion-Light-Year Little Red Dots as Distant Galaxies
Updated
Updated · Livescience.com · Aug 9
James Webb Recasts 10-Billion-Light-Year Little Red Dots as Distant Galaxies
3 articles · Updated · Livescience.com · Aug 9
Summary
Fresh JWST observations of the Saguaro galaxy suggest many “little red dots” are not a new cosmic class but ordinary galaxies seen so far away that only their bright red cores remain visible.
Computer models pushed Saguaro—about 10 billion light-years away and seen 3.3 billion years after the Big Bang—to early-universe distances, where its spiral arms faded and it resembled the compact infrared smudges in JWST deep fields.
Those objects appear in large numbers roughly 600 million years after the Big Bang and seem to vanish less than 1 billion years later, a pattern the new work says may reflect changing appearance rather than disappearance.
Data from Hubble and Chandra backed the match, including the Saguaro core’s weak X-ray signal, and researchers now plan to find more nearby analogs to trace how galaxies and supermassive black holes evolved together.