M15 (The Horse's Nose Cluster)

M15, NGC 7078, Globular Star Cluster, Constellation: Pegasus, Size 12.3' x 12.3', Magnitude 6.40

Image Details:

• Scope: 1995 Celestron Ultima 8 OTA.
• Mount: Celestron AS-GT (goto CG5).
• Camera: Meade DSI Color.
• Configuration: f/3.3 focal reducer, both spacers.
• Effective Focal Length: 609mm, f/3.
• Exposure:  20 images @30 seconds.
• Filter: Meade IR blocking filter.
• Acquisition: Meade Envisage. Quality = 30%.
• Guiding: None.
• Location: Deep South Regional Star Gaze, Camp Ruth Lee, near Clinton, Louisiana.
• Date: 30 October 2005.
• Post Processing: Meade IP.
• Photoshop: Unsharp Masking, Levels, JPG conversion.

Comments: This globular star cluster, which may lie about 35,000 light years from us, is notable for a couple of reasons. First, it's quite easy to locate, being only 4 degrees from bright Enif, Epsilon Pegasi. The cluster is also easy to see, even in the city with small scopes, due to its amazingly bright core. The fact that it is fairly compact and composed of stars of magnitudes 13 and dimmer means a 6 inch telescope at high magnification will be needed  to resolve many stars. Why is the core of this glob bright? M15 is a source of X-rays, leading astronomers to hypothesize that a black hole lies at its center. Scientific opinion as to the existence of an M15 black hole has gone back and forth over the years, however.

I was happy with this image, with its satisfyingly small stars and good color rendition. I've shot this object with slightly longer focal lengths from light polluted sites and been fairly pleased with the results, but I like this one best so far; it give the best impression of M15's blazing central regions.

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