Astronomers may have solved the decades-long cosmic murder mystery of what kills most galaxies in the universe: They are strangled to death, so they can no longer create new stars.
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.
