m10

M10 most commonly refers to Messier object 10, a globular star cluster in the constellation Ophiuchus. It is one of the objects in the Messier catalog compiled in the 18th century to help astronomers distinguish diffuse objects from comets. M10 is a densely packed cluster containing a predominantly old, metal-poor stellar population. It lies roughly 13,000 light-years from Earth and has an apparent size of about 20 arcminutes. Through telescopes, it appears as a relatively compact, rounded haze with a rich population of red giant stars. M10 is widely used in studies of globular cluster dynamics, stellar evolution, and the chemical enrichment history of the Milky Way.

In other contexts, the designation M10 is used as an alphanumeric code for various, unrelated purposes. It appears as a road or motorway designation in some national networks, and as a model number or product identifier in different industries. Because M10 is a short, generic code, its precise referent depends on jurisdiction and field. When encountering the term, readers typically rely on surrounding context or a disambiguation resource to determine which M10 is being referenced.