Sections

Catalogues

Tools and Links

Galactic Map

Show the direction and distance to this star cluster on the Galactic Map.

M23

Collinder 356, Melotte 184, NGC 6494

Open Star Cluster in Sagittarius

Show on Sky Map

Proper Name	None
Messier Number	M23
NGC/IC Number	NGC 6494
Other Designations	Collinder 356, Melotte 184
Constellation	Sagittarius
Right Ascension	17h 57m 4s
Declination	-18° 59' 6"
Distance	c.2,400 light years c.700 parsecs
Magnitude	Apparent: +5.5 Absolute: -3.5
Diameter	Apparent: 29' Actual: 17 light years
Number of Stars	c. 900
Optimum Visibility	July
Notes	M23 is one of a host of clusters and nebulae running along the Milky Way in the western parts of Sagittarius, in the direction of the Galaxy's core. It covers an area of the sky closely equivalent to that covered by the disc of the Moon.

This is a relatively young star cluster, probably no more than two hundred million years old. Consisting primarily of blue stars, it has some similarities to the better known Pleiades, but is somewhat more developed and about six times farther away from Earth.

The scattering of young blue stars that lie in the heart of the star cluster known as M23, in the constellation of Sagittarius.

The star cluster known as Messier 23 lies almost exactly in the direction of our Galaxy's core. It is more than 2,000 light years nearer to the centre than the Sun.

Indexes

Related Entries

v2.1g