Globular Cluster M5
19.10.1995

The globular cluster M5, pictured above, contains roughly 100,000 stars. These stars formed together and are gravitationally bound. Stars orbit the center of the cluster, and the cluster orbits the center of our Galaxy. So far, about 160 globular clusters are known to exist in a roughly spherical halo around the Galactic center.

NGC 1316: After Galaxies Collide
4.04.2005

How did this strange-looking galaxy form? Astronomers turn detectives when trying to figure out the cause of unusual jumbles of stars, gas, and dust like NGC 1316. A preliminary inspection indicates that NGC 1316 is an enormous elliptical galaxy that includes dark dust lanes usually found in a spiral.

M80: A Dense Globular Cluster
7.07.1999

If our Sun were part of M80, the night sky would glow like a jewel box of bright stars. M80, also known as NGC 6093, is one of about 250 globular clusters that survive in our Galaxy.

M3: Inconstant Star Cluster
15.04.2007

Star clusters appear constant because photographs of them are frozen in time. In reality, though, cluster stars swarm the center and frequently fluctuate in brightness. Although the time it takes for stars to cross...

M72: A Globular Cluster of Stars
12.05.2010

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. Many globular clusters were destroyed over the eons by repeated fateful encounters with each other or the Galactic center.

A Flock of Stars
6.09.2008

Only a few stars can be found within ten light-years of our lonely Sun, situated near an outer spiral arm of the Milky Way galaxy. But if the Sun were found within one of our galaxy's star clusters, thousands of stars might occupy a similar space.

A Flock of Stars
13.12.2003

Only a few stars can be found within ten light-years of our lonely Sun, situated near an outer spiral arm of the Milky Way galaxy. But if the Sun were found within one of our galaxy's star clusters, thousands of stars might occupy a similar space.

The Planet, the White Dwarf, and the Neutron Star
18.07.2003

A planet, a white dwarf, and a neutron star orbit each other in the giant globular star cluster M4, some 5,600 light-years away. The most visible member of the trio is the white...

M13: The Great Globular Cluster in Hercules
27.05.2010

In 1716, English astronomer Edmond Halley noted, "This is but a little Patch, but it shews it self to the naked Eye, when the Sky is serene and the Moon absent." Of course...

In the Center of 30 Doradus
4.10.1997

In the center of 30 Doradus lies a huge cluster of the largest, hottest, most massive stars known. The center of this cluster, known as R136, is boxed in the upper right portion of the above picture.