Astronomy
The Cause of Gamma-Ray Bursts in Distant Galaxies
Quick fact
Long-duration gamma-ray bursts are likely produced when a star over 20 times the Sun's mass collapses directly into a black hole, while short bursts come from merging neutron stars—some of which emit gravitational waves.
Why this is interesting
Imagine an explosion so bright it outshines an entire galaxy for a few seconds, and it happens a billion light-years away. What could possibly cause that?