M10, also cataloged as NGC 6254, is a bright globular cluster in Ophiuchus.
What It Is
M10, also cataloged as NGC 6254, is a bright globular cluster in Ophiuchus. It is a dense, spherical swarm of old stars orbiting in the halo of the Milky Way, with stars packed most tightly toward the center.
History
Charles Messier discovered M10 on May 29, 1764 while cataloging fuzzy objects that could be mistaken for comets. Like many globular clusters, it first appeared as a round unresolved glow; later telescopes revealed it as a rich cluster of individual stars.
Science Notes
- NASA lists M10 at about 15,000 light-years away with an apparent magnitude of 6.4, bright enough for binoculars under good skies.
- Hubble ultraviolet observations show a large population of blue stragglers, stars that look younger and bluer than most of the cluster.
- Blue stragglers likely form through stellar collisions or close interactions, both easier to produce in the crowded environment of a globular cluster.
- SEDS lists M10 as about 63 light-years across, making the photographed cluster a compact city of ancient stars.
- M10 lies in Ophiuchus near another Messier globular, M12, so the region is rich in Milky Way halo clusters.
- distance
- ~15,000 light-years
- diameter
- ~63 light-years
- apparentMagnitude
- +6.4
- constellation
- Ophiuchus
- objectType
- Globular cluster
- coordinates
- RA 16h 57m 09s, Dec -04 deg 06 min 01 sec
- bestObserved
- July from mid-northern latitudes
