In a rare cosmic spectacle, astronomers have observed two galaxies engaged in a high-speed collision, approximately 11 billion light-years away. One galaxy, powered by a supermassive black hole ...

Is dark energy changing, or is it just more of the same? Last month, astronomers announced the startling finding that dark energy – which is thought to cause the accelerating expansion of the ...

“That’s why we call it a ‘cosmic joust,’” said Pasquier Noterdaeme, a researcher for the Paris Institute of Astrophysics and the French-Chilean Laboratory for Astronomy in Chile who was ...