We measure the extremely long distances between things in space by light years. A light year is the distance that light travels in one Earth year. Light travels at about 300,000 kilometres per second.

Imagine a star powered not by nuclear fusion, but by one of the universe’s greatest mysteries—dark matter. Scientists have ...

New supercomputer simulations suggest the Milky Way could be surrounded by dozens more faint, undetected satellite ...

The Milky Way could have many more satellite galaxies than scientists have previously been able to predict or observe, ...

Dark matter is one of nature's most confounding mysteries. It keeps particle physicists up at night and cosmologists glued to ...

Scientists predict up to 100 invisible galaxies may orbit the Milky Way, hiding just beyond our current detection limits.

New simulations suggest that dozens of ultra-faint “ghost” galaxies may be orbiting the Milky Way, hidden from current ...

“Dark matter interacts gravitationally, so it could be captured by stars and accumulate inside them. If that happens, it might also interact with itself and annihilate, releasing energy that heats the ...

There may be many more satellite galaxies in the Milky Way than have been observed, according to new Durham University ...