Artemis 2 will launch four astronauts around the moon no sooner than April 1. Why won't this quartet land on the lunar surface?
It's not often that astronomers can observe huge changes in a galaxy's brightness over the course of a few years. Most galaxies change in brightness (and other characteristics) over millions or billions of years. So, when images of the 10-billion-light-year distant galaxy J0218-0036 showed that it dimmed down by a twentieth of its previous brightness in just 20 years, observers were surprised. What could cause it to do that? That's not "normal" for AGN.

