The gas is so hot, between 10 million and 100 million degrees Celsius, that it radiates in powerful X-rays. When you purchase through links on our site, we may earn an affiliate commission. Here’s how ...

A massive, highly active cluster of sunspots produced over a dozen major solar flares on the far side of the Sun. The active ...

Astronomers have spotted a mysteriously mature “baby cluster” of galaxies in the early universe, scarcely a billion years after the big bang. Although not a full-grown, full-blown galaxy cluster, the ...

might be proof that hot gases there account for a large fraction of the previously unseen matter in the universe.

The galaxy cluster is filled with bubbles blown into X-ray emitting gas, producing some of the deepest sounds ever heard. When you purchase through links on our site, we may earn an affiliate ...

Look closely at this image from NASA's Hubble Space Telescope and you'll see galaxies of various shapes and sizes clustered ...