The brightest objects in the universe have massive black holes at their hearts.
Quasars (“quasi-stellar radio sources”) can be brighter than entire galaxies, and they’re thought to be fueled by the friction and heat of stuff that’s getting swallowed up by a black hole. (Although light can’t escape a black hole, it can escape from the event horizon—the boundary and point-of-no-return surrounding the black hole.)
Now, it turns out that the quasar nearest to Earth, located 600 million light-years away in a galaxy called Markarian 231, is actually built around two twirling black holes. It’s a first-of-its-kind type of find, and scientists think there could be a lot more quasars with binary hearts out there.
The supermassive black hole is 40 million times as massive as the sun and powers a quasar that existed 700 million years after the Big Bang.
The asteroid zoomed by Earth at a perfectly safe distance of around 1.8 million miles (2.9 kilometers).
Images show surprise changes to the spacecraft as it interacted with the atmosphere.