As the first human ancestors walked the Earth, our galaxy's central black hole might have been in the process of blasting away most of the galaxy's normal matter.
A new record for the most distant galaxy cluster has been set. Astronomers say the cluster, 11.1 billion light-years away, might have been caught right after birth.
A strong signal from a sunlike star sparked speculation this week that we might - at last - have heard from an alien civilization. Now astronomers say ... no.
No, not Nibiru. Theoretical astronomers describe how a hypothetical Planet 9 could hurtle Jupiter into interstellar space when the sun dies, billions of years from now.
NASA TV will broadcast live coverage on Thursday of a 6.5-hour spacewalk by 2 astronauts aboard ISS. Coverage will start at 6:30 a.m. EDT (1030 UTC). The spacewalk will begin about 8 a.m. EDT (1200 UTC).
Although it's relatively nearby, Dragonfly 44 was missed for decades by astronomers because it's very dim. But there's more to this galaxy than meets the eye.
Asteroid 2016 QA2 was twice as big as the space rock that entered over Russia in 2013, breaking windows in 6 Russian cities. It passed safely Saturday night.