Messier 10 (M10)

Also Known as: NGC 6254, GCI-49

Object Type: Globular Cluster

Constellation: Ophiuchus

Distance from Earth: 14,300 Light years

Apparent Magnitude: 6.4

Coordinates: RA 16H 57M 8.92S DEC -04 deg 05 min 58.07 sec

Actual Size: 80 light years in diameter.

Apparent Dimensions: 20 arc minutes.

Discovered by: M10 was discovered by Charles Messier on May 29, 1764. Messier added it to his catalogue as object number 10, describing it as a “nebula, without stars, in the belt of Ophiuchus; near the 30th star of that constellation, of sixth magnitude, according to Flamsteed. This nebula is beautiful & round; one can only see it with difficulty in an ordinary telescope with a focal length of 3-feet.”
William Herschel resolved the stars and recognized it as a cluster.

Description: M10 is a rich bright globular cluster containing about 100,000 stars with the core region consisting of 14% binary stars.
It lays about 16,000 light years from the galactic center. The cluster is classified as moderately metal-poor and there is evidence indicating that it is enriched by elements produced in Type II supernovae and the s-process (slow-neutron-capture process) in massive stars.
The stars in M10 have only 3.5 percent of the heavy elements found in the Sun, pointing to an age of 11.4 billion years. This makes M10 one of the younger globular clusters known.
The cluster’s core will be the last part to survive and will likely be around for another 15 to 20 billion years. It will eventually be torn apart by gravitational forces of the Milky Way as it keeps passing through the galactic disk.
Messier 10 has a spatial diameter of 83 light years, but small telescopes (3-inch) reveal about half the cluster’s size – roughly 8 to 9 minutes of arc – and its bright central region, which spans roughly 35 light years. 6-inch or 8-inch telescopes show the cluster extending across 15.1 arc minutes and reveal a large, bright central core.
Meanwhile, deep images reveal M10 to span some 20 arc minutes of apparent sky and resolve stars across the entire area of the cluster.
The cluster is about two thirds the size of the full Moon, but its outer regions are very dim.

Click Below Image(s) for Full Size:

With a visual magnitude of 6.4, even the cluster’s bright core is too faint to be seen without binoculars.
Small telescopes reveal about half of the cluster’s size roughly 8 to 9 arc minutes and its bright central core which spans 35 light years.
A 6 or 8 inch scope shows the cluster across 15.1 arc minutes and reveals a bight central core. The cluster is visibly large spanning almost 2/3 the size of the full Moon.
M10 is very close to M12, about 2,000 light years.

The best time to observe M10 is May-July.

Platesolve

M10 Globular Cluster

Imaging Details
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