If we took Earth and Venus - and had them orbit a cool, red star not too far away - could the James Webb Space Telescope tell which planet was habitable?
Scientists have detected 5 supermassive black holes previously clouded from view. The research suggests there are millions more hidden black holes out there.
A new theoretical model focuses on the spiral arms now known to exist around some young stars. The spiral arms may enable rocky planets like Earth to form.
Sinkholes on Earth happen when a subsurface cavern collapses. On the comet, the caverns may be created by ices turning to gas, as the comet nears the sun.
On June 15, a monster black hole started showing signs of extraordinary activity that hasn't happened since 1989. Astronomers around the world are watching.