Comet Leonard Before Star Cluster M3
12.12.2021

Comet Leonard is now visible to the unaided eye -- but just barely. Passing nearest to the Earth today, the comet is best seen this week soon after sunset, toward the west, low on the horizon.

M55: Globular Star Cluster
18.09.2004

The fifty-fifth entry in Charles Messier's catalog, M55 is a large and lovely globular cluster of around 100,000 stars. Only 20,000 light-years away in the constellation Sagittarius, M55 appears to earth-bound observers to be nearly 2/3 the size of the full moon.

Mars and the Star Clusters
19.04.2006

This evening's skyscape includes a view similar to this one, recorded in western skies on April 16 - an orange-hued planet Mars wandering near rich open star cluster M35. Also notable is fainter star cluster NGC 2158, just above and left of M35.

M72: A Globular Cluster of Stars
19.08.2012

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.

Star Cluster R136 Bursts Out
21.12.2009

In the center of star-forming region 30 Doradus lies a huge cluster of the largest, hottest, most massive stars known. These stars, known collectively as star cluster R136, were captured above in visible light by the newly installed Wide Field Camera peering though the recently refurbished Hubble Space Telescope.

Star Cluster, Spiral Galaxy, Supernova
25.05.2017

A cosmic snapshot from May 19, this colorful telescopic field of view spans about 1 degree or 2 full moons on the sky. Spiky in appearance, foreground Milky Way stars are scattered toward...

The Hyades Star Cluster
22.01.2020

It is the closest cluster of stars to the Sun. The Hyades open cluster is bright enough to have been remarked on even thousands of years ago, yet is not as bright or compact as the nearby Pleiades (M45) star cluster.

Palomar 6: Globular Star Cluster
19.10.2021

Where did this big ball of stars come from? Palomar 6 is one of about 200 globular clusters of stars that survive in our Milky Way Galaxy. These spherical star-balls are older than our Sun as well as older than most stars that orbit in our galaxy's disk.

The Quintuplet Star Cluster
21.09.1999

Bright clusters of stars form and disperse near the center of our Galaxy. Four million years ago the Quintuplet Cluster, pictured above, formed and is now slowly dispersing. The Quintuplet Cluster is located within 100 light-years of the Galactic center, and is home to the brightest star yet cataloged in our Galaxy: the Pistol Star.

M3: Inconstant Star Cluster
12.10.2004

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...