For the mostly harmless denizens of planet Earth, the brighter stars of open cluster NGC 2169 seem to form a cosmic 37. Did you expect 42? From our perspective, the […]

It was larger than the Earth. It was so big you could actually see it on the Sun’s surface without magnification. It contained powerful and tangled magnetic fields as well […]

Northern lights don’t usually reach this far south. Magnetic chaos in the Sun’s huge Active Region 3664, however, produced a surface explosion that sent a burst of electrons, protons, and […]

Right now, one of the largest sunspot groups in recent history is crossing the Sun. Active Region 3664 is not only big — it’s violent, throwing off clouds of particles […]

Relax and watch two black holes merge. Inspired by the first direct detection of gravitational waves in 2015, this simulation plays in slow motion but would take about one third […]

What would it look like to circle a black hole? If the black hole was surrounded by a swirling disk of glowing and accreting gas, then the great gravity of […]

What happens when a black hole devours a star? Many details remain unknown, but observations are providing new clues. In 2014, a powerful explosion was recorded by the ground-based robotic […]

This is how the Sun disappeared from the daytime sky last month. The featured time-lapse video was created from stills taken from Mountain View, Arkansas, USA on 2024 April 8. […]

What happens to a star that goes near a black hole? If the star directly impacts a massive black hole, then the star falls in completely — and everything vanishes. […]