"M 24"* Star Cloud in Sagittarius

Includes B 92 / B 93 and NGC 6603

Center of field at approximately: RA 18 hours 15 minutes 50 seconds, Dec -18 degrees 11 minutes 32 seconds

Size: ~120' Magnitude: -- Class: star cloud

North is up

West to the right

Telescope:

 8" f5 Newtonian reflector

Camera:

Miranda Laborec 35mm camera, manually guided, hypered Kodak Technical Pan 2415 film, 42 F outside temp

Image:

No filter, 25 minutes, 09/07/1986

Processing:

D-19, 5.5 minutes @ 68F, 35mm negative scanned with Polaroid SprintScan 4000 (4000 dpi)

Scan is a crop from 35mm negative, scan processed in Photoshop CS5.1

 

Location:

Mt Pinos (Condor Lookout), CA

Notes:* If "M 24" is considered a 2 degree Star Cloud (or Open Cluster), it is way to large for my current imaging field (about 31' x 46'). However, I can still image various parts of what is included in the star cloud ... B 92 / 93 and NGC 6603. In an effort to 'fill in' my Messier images page, I will post what film images I have. My film scanner is not presently hooked up, so I am using scans made for my old film website from the early 2000's.

Most of the film scans from the 8" f5 Newtonian reflector were centered on the object of interest, and were generally scanned to file as a 2000 x 2000 pixel crop of the 35mm negative. This image is a scan of about 70% of the 35mm negative (2376 x 3604 pixels).

Reduced in Photoshop to 1024 pixels, and saved under "Save for Web & Devices".

These descriptions from the on-line Edward Emerson Barnard "A Photographic Atlas of Selected Regions of The Milky Way":

92
α(2000)18h 15m 35s, δ(2000) -18 14
Galactic Coordinates 13, -1
 Black spot, 15 N and S, 9 E and W. This black spot, known to me in my early days of comet seeking, is very sharply defined on its east edge but less definite on the west. There is a twelfth-magnitude star near the middle with several other small stars (see ibid., 38, 496, 1913, Plate XX, for an account of this remarkable object).
93
α(2000)18h 16m 54s, δ(2000) -18 04
Galactic Coordinates 13, -1
 Cometary, a sharply defined black head 2 in diam., with a diffused tail 15 long running S, 20 NE of B 92

From the NGC / IC Project:

Contemporary Visual Observation(s) for NGC 6603
NGC 6603 = Cr 374
18 18 27 -18 24.4
Size 5

13.1": excellent resolution into 30-50 faint stars including a string oriented 
NW-SE running through the center.  The outline forms an arrowhead shape pointing 
to the E.  Situated in the NE corner of M24 in a glorious region of the Small 
Sagittarius Starcloud!  Located 4' N of mag 8 SAO 161294.  The dark nebula B93 
lies ~30' NW.

17.5": between 50 and 70 stars are resolved, extremely dense.

- by Steve Gottlieb
Historical Research Notes / Correction for NGC 6603
NGC 6603, a relatively small and faint cluster, is not M24.  The Messier 
object is actually IC 4715, which see for more. - Dr. Harold G. Corwin, Jr.
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The CDS Aladin Previewer returns 18h 16m 47.9s, -18h 33m 00s when entering "M 24" in the search box.
The CDS SIMBAD Astronomical Database returns 18h16.8m -18 33 when entering "M 24" in the search box. (Queries - by identifier)
The STScI Digitized Sky Survey returns 18h 16m 48.00s, -18d 33m 00.0s when entering "M 24" in the search box.
All sets of coordinates are basically in the center of the (small Sagittarius) Star Cloud.