IC 1805: The Heart Nebula

What energizes the Heart Nebula?

Lenticular Clouds over Mount Etna

What's happening above that volcano?

The Conjunction of the 46p/wirtanen comet, the hyades cluster and the Pleiades cluster

Astronomy Picture of the Day: Meteor before Galaxy

What's that green streak in front of the Andromeda galaxy? A meteor.

Astronomy Picture of the Day: Spiral Galaxy NGC 6744

Beautiful spiral galaxy NGC 6744 is nearly 175,000 light-years across, larger than our own Milky Way.

Astronomy Picture of the Day: From the Galactic Plane through Antares

Behold one of the most photogenic regions of the night sky, captured impressively.

Trifid Nebula and his companion

M20 and M21

Astronomy Picture of the Day: A Plurality of Singularities at the Galactic Center

A recent informal poll found that astronomers don't yet have a good collective noun for a group of black holes, but they need one.

Astronomy Picture of the Day: Galaxies in the River

Large galaxies grow by eating small ones. Even our own galaxy practices galactic cannibalism, absorbing small galaxies that get too close and are captured by the Milky Way's gravity.

Astronomy Picture of the Day: The View Toward M101

Big, beautiful spiral galaxy M101 is one of the last entries in Charles Messier's famous catalog, but definitely not one of the least.