WASHINGTON—The 2019 release of the first image of a black hole was hailed as a significant scientific achievement. But truth be told, it was a bit blurry—or, as one astrophysicist involved in the effort called it, a “fuzzy orange donut.” Scientists on Thursday unveiled a new and improved image of this black hole—a behemoth at…

WASHINGTON—Astronomers have detected an act of extreme violence more than halfway across the known universe as a black hole shreds a star that wandered too close to this celestial savage. But this was no ordinary instance of a ravenous black hole. It was one of only four examples—and the first since 2011—of a black hole…