M 23 (NGC 6494, Lund 793) Open Cluster in Sagittarius

Located at: RA 17 hours 56 minutes 54 seconds, Dec -19 degrees 01 minutes 00 seconds

Size: 27' (25') Magnitude: 5.5 Class: II 2 r

North is up

West to the right

Telescope:

8" f5 Newtonian reflector

Camera:

 ST-8XME, self-guided, binned 1x1, temp -15c, camera control MaxIm DL 4.56

Image:

Lumicon Deep Sky filter, 120 minutes (12 x 10 minute subs), 08/17/2007

Processing:

CCDStack 1.2, Photoshop 7.0

Location:

 Rolling Roof Observatory, Thousand Oaks, CA 91360 (+34d 13m 29s -118h 52m 20s)

Notes:

A large, magnificent open cluster in a rich Milky Way field.

According to "Star Clusters", by Brent Archinal and Steven Hynes, the size of this open cluster is 25 arc minutes.

From the NGC / IC Project:

Contemporary Visual Observation(s) for NGC 6494

NGC 6494 = M23 = E589-SC22 = Cr 356
17 57 05 -18 59.1
V = 5.5;  Size 27

13.1": bright, large, rich, appears fully resolved.  Very pretty open cluster.

8": bright, fairly large with long star lanes to the edge of the field.

- by Steve Gottlieb