Not registered yet?
The best-selling astronomy magazine
How do you make a black hole with the mass of 800 million Suns less than 700 million years after the Big Bang?
This galaxy has a relatively small supermassive black hole, but it’s not to be outdone.
Using X-ray light bouncing off the disk of matter around a black hole, astronomers have mapped the system in better detail than ever before.
Merging black holes could get a “kick” that sends them flying off into space.
When stars get too close to a black hole, they go out with a whimper, not a bang.
This star disappeared from sight, forming a black hole.
To map the universe, astronomers string together distance measurements to ever-farther objects, like climbing rungs on a cosmic ladder.
The key question is: Did galaxies, stars, or black holes come first?
For most of recorded history, the answer was simple: The universe has always existed and always will. Few people challenged the dogma or even suspected it might not be true.
The concept of black holes goes all the way back to the 1780s.
A beautiful crescent Moon appears 2° to the right of a brilliant Venus just 45 minutes after sunset tonight.
Earth reaches perihelion, the closest point to the Sun during its year-long orbit, at midnight EST tonight. The two then lie 91.4 million miles (147.1 million kilometers) apart.
Voyager 2 shut down an instrument heater, but is still going strong, more than forty years after launch.
One of the hottest periods in Earth's history was likely caused by a particularly eccentric orbit.
Hubble captured the dying breath of a star shredding itself apart.
An artificial comet holds secrets to Earths life
Mars changes color with the seasons each year - here's why.