NGC 6603

Open Cluster within the M24 Star-Cloud, Sagittarius

September 2021. Observatorio El Sauce, Chile

NGC 6603 is an open cluster discovered by John Herschel on July 15, 1830 located in Sagittarius constellation. Situated within the brightest part of star cloud Messier 24, 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. Many sources improperly identify NGC 6603 as Messier 24.

Telescope: Astro Physics 155EDF (TCC) f5.4
Mount: Astro Physics 1600GTO
Camera: FLI PL29050 / CFW2-7
Guider: Agena Starguide II / SBIG STi

L: 49×5 mins = 245 mins, R: 24×5 mins = 120 mins, G: 24×5 mins = 120 mins, B: 24×5 mins = 120 mins

Total Imaging Time: 10h 05m

Data Imaged remotely over 3 nights during September 2021.
Imaged from Observatorio El Sauce, Chile, in partnership with Fred Espenak.
Data acquisition & Processing by David Churchill.