M54 also known as Messier 54 or NGC 6715, is a globular cluster located in the constellation Sagittarius.  It was discovered by Charles Messier in 1778 and included in his catalog of comet-like objects.

http://en.wikipedia.org/wiki/Messier_54

ABOUT THE IMAGE

DATE/TIME:  The evening of August 25th, 2013.

CAMERA:  Canon XSI, 450Da

TELESCOPE:  Celestron C9.25 SCT @ F/6.3

MOUNT:  Celestron CGE Pro

ISO SETTING:  800

EXPOSURES:  23

EXPOSURE LENGTH:  200sec.

TOTAL EXPOSURE LENGTH:  1hrs, 16min, 40sec.

SUBTRACTIONS:  16 darkframes, 40flat frames, 16darkflat frames

CAPTURE SOFTWARE:  MaximDL

STACKING SOFTWARE:  Deep Sky Stacker

PROCESSING:  Photoshop CS3