The galaxy’s disk is about 100,000 light years across, but the halo—which contains the oldest stars in the galaxy—extends for hundreds of thousands of light-years in every direction.

This stream, dubbed Stream N, harbors red giant branch (RGB) stars notably more metal-poor than stars residing in the galaxy's disk and the inner stellar halo. The astronomers assume that Stream N ...

Scientists have found dark matter dominating the halos of two supermassive black holes 13 billion light years away.

They are the most luminous objects in a galaxy, outshining all the stars. When light from a quasar reaches a CGM, it is absorbed by the different elements forming the halo. “The Hubble readings ...

When you point a telescope toward the Pegasus constellation, you can discover a scene where the Milky Way stars and distant galaxies unfold. NGC 7814, located in the center, occupies an area that ...