High Energy Andromeda
6.01.2016

A mere 2.5 million light-years away, the Andromeda Galaxy, also known as M31, really is just next door as large galaxies go. In this (inset) scan, image data from NASA's Nuclear Spectrosopic Telescope...

Zooming in on Star Cluster Terzan 5
23.03.2019

Globular clusters once ruled the Milky Way. Back in the old days, back when our Galaxy first formed, perhaps thousands of globular clusters roamed our Galaxy. Today, there are less than 200 left. Over the eons, many globular clusters were destroyed by repeated fateful encounters with each other or the Galactic center.

The Small Cloud of Magellan
4.01.2021

What is the Small Magellanic Cloud? It has turned out to be a galaxy. People who have wondered about this little fuzzy patch in the southern sky included Portuguese navigator Ferdinand Magellan...

Caught in the Afterglow
24.11.2011

In this artist's illustration, two distant galaxies formed about 2 billion years after the big bang are caught in the afterglow of GRB090323, a gamma-ray burst seen across the Universe. Shining through...

Hanny s Voorwerp
9.02.2011

Hanny's Voorwerp, Dutch for "Hanny's Object", is enormous, about the size of our own Milky Way Galaxy. Glowing strongly in the greenish light produced by ionized oxygen atoms, the mysterious voorwerp is below spiral galaxy IC 2497 in this view from the Hubble Space Telescope.

NGC 1818: A Young Globular Cluster
16.01.1999

Globular clusters once ruled the Milky Way. Back in the old days, back when our Galaxy first formed, perhaps thousands of globular clusters roamed our Galaxy. Today, there are perhaps 200 left. Many globular clusters were destroyed over the eons by repeated fateful encounters with each other or the Galactic center.

Zooming in on Star Cluster Terzan 5
20.09.2016

Globular clusters once ruled the Milky Way. Back in the old days, back when our Galaxy first formed, perhaps thousands of globular clusters roamed our Galaxy. Today, there are less than 200 left. Over the eons, many globular clusters were destroyed by repeated fateful encounters with each other or the Galactic center.

M82 After the Crash
11.03.2001

When did the Cigar Galaxy light up? Evidence indicates how M82, the Cigar Galaxy, became so bright and peculiar: it collided with neighboring galaxy M81. Astronomers become detectives, however, when trying to figure out when this collision occurred.

Messier 101
1.03.2006

Big, beautiful spiral galaxy M101 is one of the last entries in Charles Messier's famous catalog, but definitely not one of the least. About 170,000 light-years across, this galaxy is enormous, almost twice the size of our own Milky Way galaxy.

APOD: 2025 June 27 Б Messier 109
26.06.2025

Big beautiful barred spiral galaxy Messier 109 is the 109th entry in Charles Messier's famous catalog of bright Nebulae and Star Clusters. You can find it just below the Big Dipper's bowl in the northern constellation Ursa Major.