Utterly amazing. A "scratch" thought to be cosmic ray noise on Hubble's detected images ended up being a 200k LY trail of blue-white star formation from a supermassive black hole being flung from its home galaxy.

Nothing like it has ever been spotted before (or perhaps has, but everyone thought it was a "scratch".... =] ).

https://hubblesite.org/contents/news-releases/2023/news-2023-010