Is J1420–0545 the largest galaxy ever discovered?

An unassuming galaxy hides a secret 15 million…

Galaxy X: The dark galaxy that doesn’t exist

Astronomers almost detected an enormous satellite galaxy…

Was the Milky Way once an active galaxy?

Two bubbles 50,000 light-years across may hold the answer.

How did Hoag’s Object form?

We normally think of galaxies as falling into two main morphological types, spiral and elliptical. Spiral galaxies have spiral arms, which wind about a central nucleus, all embedded in a halo containing stars, globular clusters, and dark matter. Elliptical galaxies are…

IGR J18245–2452: The most important neutron star you’ve never heard of

Astronomers have spent thirty…

Here’s what I Zwicky 18 can tell us about the first stars in the universe

A blue dwarf galaxy only 59…

Void galaxies: The true island universes

Why Pisces A and B could hold the key to understanding the…

The strange story of calcium-rich supernovae

When SN 2005E exploded, it made a big splash — and not…

Andromeda’s double nucleus

Most galaxies only have one nucleus at their center. Why does Andromeda have two?

The centers of galaxies are often extremely turbulent places. They usually contain supermassive black holes — weighing…