NGC 6603
Encyclopedia
NGC 6603 is an open cluster
Open cluster
An open cluster is a group of up to a few thousand stars that were formed from the same giant molecular cloud and have roughly the same age. More than 1,100 open clusters have been discovered within the Milky Way Galaxy, and many more are thought to exist...

 discovered by John Herschel
John Herschel
Sir John Frederick William Herschel, 1st Baronet KH, FRS ,was an English mathematician, astronomer, chemist, and experimental photographer/inventor, who in some years also did valuable botanical work...

  around 1825-33.

Situated within the brightest part of star cloud M24
Sagittarius Star Cloud
The Sagittarius Star Cloud is a star cloud in the constellation of Sagittarius, approximately 600 light years wide, which was discovered by Charles Messier in 1764....

, it is classified by Shapley as type "g". This cluster consists of about 30 stars in a field of about 5 arc minutes in diameter, and is about 9400 light years remote. Thus its linear diameter should be about 14 light years. The hottest stars are about B9 (pointing to an intermediate age of several 100 million years, an estimate of which is not known to the present author), and the brightest of photographic mag 14.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK