2019: Galaxy SDSS1335+0728 suddenly brightens, possibly due to active black hole.

Astronomers have observed a galaxy suddenly brighten and remain lit, possibly due to a massive black hole at its center suddenly awakening. In late 2019, the previously quiet galaxy SDSS1335+0728 began shining brighter than ever before and is still increasing in brightness today. Researchers believe this unprecedented event may be the first time they have witnessed a black hole becoming active in real time.