Here's the original article, without the odd chatgpt headlines:
https://www.stsci.edu/contents/news-releases/2025/news-2025-...
So what does this do to our estimates of the ratio of regular matter in the universe?
Is there an animation or blink visualization of this time evolution?
There is an 11 second video across a few weeks embedded. From the caption:
"This time-lapse video using data from NASA’s James Webb Space Telescope highlights the evolution of one light echo in the vicinity of the supernova remnant Cassiopeia A. A light echo is created when a star explodes or erupts, flashing light into surrounding clumps of interstellar dust and causing them to shine in an ever-expanding pattern."