Astrophysicists trace the origin of valuable metals in space, from colliding stars to merging galaxies

This artist’s impression shows two tiny but very dense neutron stars at the point at which they merge and explode. ESO/L. Calçada/M. Kornmesser, CC BY

Billions of light years away in a remote part of the universe, two neutron stars – the ultradense remnants of dead stars – collided. The catastropic cosmic event sent light and particles, including a sudden flash of gamma rays, streaming through the universe. These gamma rays traveled for 8.5 billion years before reaching Earth.

In a new study, our team of astrophysicists examined this gamma-ray signal. We learned that the stellar collision it came from was likely caused by an even more catastrophic encounter – a merger between two galaxies.