A major survey verifies 3,500 gravitational lenses, offering new tools to map dark matter and track cosmic expansion.

Galaxies are clouds of stars that range in both size and composition. Some contain hundreds of millions of stars while the largest galaxies can contain trillions of stars. And while it’s not entirely ...

A new study has found that a hidden bias in galaxy models can skew gravitational-wave measurements of how fast the universe is expanding. That finding complicates one of astronomy’s most promising ...

Using the James Webb Space Telescope (JWST), scientists found that many galaxies started as thick discs before forming the thin discs we see now. This discovery helps answer a long-standing mystery ...

The universe may be a little darker after a recent discovery has shown that there could be fewer galaxies populating it. A previous measurement by Hubble Space Telescope suggested there were 2 ...

T he first time I heard about galaxies without dark matter, I was sitting in my very first graduate class at the University of São Paulo. It was 2018, and the discovery had just ...