Messier 10 is a globular cluster nestled in the constellation Ophiuchus. Its position near the celestial equator makes it visible from both hemispheres. Discovered by the French astronomer Charles Messier in May 1764, M10 holds the distinction of being one of the first objects included in his catalogue of non-cometary celestial phenomena.
Appearance
M10 is characterized as a spherical collection of stars, known as a globular cluster. It contains hundreds of thousands to millions of stars that are densely packed together by gravitational forces. When observed through a telescope or binoculars, it appears as a fuzzy, round patch of light. The cluster features a dense core surrounded by a halo of stars, and under optimal viewing conditions, individual stars can be resolved in its outer regions.
Characteristics
The cluster has an apparent magnitude of approximately 6.4, making it visible to observers equipped with binoculars or small telescopes under dark sky conditions. M10 has a diameter of about 83 light-years and is located roughly 14,300 light-years away from Earth. The stars in M10 are estimated to be around 11 to 12 billion years old, indicating that they formed early in the history of the universe. The cluster is primarily composed of older stars, classified as Population II stars, which are metal-poor and typically found in globular clusters.
Observation
The constellation Ophiuchus is positioned near the celestial equator, allowing M10 to be observed from both hemispheres. Because of its equatorial location, the cluster can be viewed year-round, although the optimal viewing months vary slightly between hemispheres. In the Northern Hemisphere, M10 is best observed from April to August, when it is high in the night sky during evening hours. It is also visible during this period from the Southern Hemisphere, where observers can spot it as well. Additionally, southern observers have a favourable viewing window from September to March, during which M10 is even better positioned in the sky. Thus, while the optimal viewing months may differ slightly based on location, M10 remains accessible to both northern and southern observers throughout the year, particularly during the April to August timeframe.
