Sagittarius Star Cloud

Messier 24
Observation data (J2000 epoch)
Constellation	Sagittarius
Right ascension	18h 17m
Declination	−18° 29′
Distance	~10 kly (3070 Pc)
Apparent magnitude (V)	4.6
Apparent dimensions (V)	90′
Physical characteristics
Radius	~300
Estimated age	220 million years[citation needed]
Other designations	Delle Caustiche, IC 4715
See also: Open cluster, List of open clusters

The Sagittarius Star Cloud (also known as Delle Caustiche, Messier 24, IC 4715) is a star cloud in the constellation of Sagittarius, approximately 600 light years wide, which was discovered by Charles Messier in 1764.

The stars, clusters and other objects comprising M24 are part of the Sagittarius or Sagittarius-Carina arms of the Milky Way galaxy. Messier described M24 as a "large nebulosity containing many stars" and gave its dimensions as being some 1.5° across, a description that fits the star cloud rather well. Some sources, improperly, identify M24 as the faint cluster NGC 6603.

M24 fills a space of significant volume to a depth of 10,000 to 16,000 light-years. This is the most dense concentration of individual stars visible using binoculars, with around 1,000 stars visible within a single field of view.

See also

• Messier object
• List of Messier objects
• New General Catalogue

References

External links

• Messier 24, SEDS Messier pages
• The Sagittarius Star Cloud on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images

Coordinates: 18^h 16.5^m 00^s, −18° 29′ 00″