M13 Great Hercules Cluster

Designations:	M13, NGC 6205
Object Type:	Globular Cluster
Constellation:	Hercules
RA:	16 hr 41.7 min	Dec:	+36 deg 27 min
Magnitude:	5.8	Size:	21 arcminutes
Distance:	23,400 light years
Discoverer:	Edmond Halley, 1714

M13 is generally considered the finest globular cluster in the northern skies, mainly because it is visible to the naked eye in a well-known grouping of stars that sails high overhead in the summer sky. It is a swollen mass teeming with perhaps 300,000 to a half-million suns spread across 140 light years or more; a typical globular contains tens of thousands to hundreds of thousands of stars. A relatively close globular ( about the same distance of M5), the Great Hercules Cluster is pleasingly bright. From dark skies and in good conditions, M13 is easily spotted as a fuzzy "star" with the naked eye, though it can be seen as a perceptible glow even through a light fog.

Telescope:	Stellarvue 80mm Apo Refractor
Focal Length:	384 mm ( 480 * 0.8x focal reducer)
Mount:	Takahashi NJP 160
Camera:	SBIG ST10XME
Guider:	SBIG ST402ME
Exposures:	10 7-minute exposures (Luminance)and 5 6-minute exposures for red, green and blue (total of 30 minutes each color)
Location:	Cicero, IN
Software:	CCDSoft for image acquisition, processed with CCDStack and Photoshop CS2