A family portrait of the Andromeda galaxy and its orbiting dwarf satellites raises questions about how galaxies evolve.

Using the Hubble Space Telescope, astronomers have discovered what seems to be a galaxy that is the most heavily dominated by ...

In the vast tapestry of the universe, most galaxies shine brightly across cosmic time and space. Yet a rare class of galaxies ...

Hubble's sharp resolution allows observers to pore over the galaxy's details, showing that it has traits of both spiral and elliptical galaxies. Its core appears unusually smooth and gas-poor, traits ...

In A Nutshell A massive star in the Andromeda Galaxy faded by more than 10,000 times over a decade and vanished from view, ...

It's 99 percent dark matter, a new study explains.

Astronomers report a supergiant star in the Andromeda Galaxy, M31-2014-DS1, collapsed directly into a black hole without a supernova, confirming predictions of failed stellar explosions.