Add Yahoo as a preferred source to see more of our stories on Google. Dark matter may have started hot and cooled during reheating after the Big Bang. (CREDIT: NASA / Goddard Space Flight Center ...

T he first time I heard about galaxies without dark matter, I was sitting in my very first graduate class at the University ...

NASA's Hubble Space Telescope captures the magnificent starry population of the Coma Cluster of galaxies, one of the densest known galaxy collections in the universe — and where the effect of dark ...

This may be remembered as one of the more important physics images of this generation. Credit: Tomonori Totani, The University of Tokyo Physicists from Japan's University of Tokyo have published a new ...

In the early 1930s, Swiss astronomer Fritz Zwicky observed galaxies in space moving faster than their mass should allow, prompting him to infer the presence of some invisible scaffolding—dark ...

Dark matter is an elusive type of matter that does not emit, reflect or absorb light, yet is estimated to account for most of the universe's mass. Over the past decades, many physicists worldwide have ...