This 10.3 magnitude globular cluster in Lynx used to be called the "Intergalactic Tramp" globular because of its extreme distance. Since then, we have found that it lies in outskirts of our Milky Way Galaxy, at about 85 percent the way to the most distant parts. Generously sized at 4.7 arcmins, most stars are 17 magnitude and fainter. As is typical of globulars, the inner blueish core is surrounded by a outer range of orange supergiants. The very bright star to its left, is 7th magnitude and is a problem to control during the deep exposures required for this very dim and distant member of our Galaxy. Below is my best shot over the years with the same instrument on 2415 film for comparison. The cluster was a completely unresolved haze with color film. It is an enlargement from the oriinal negative that is the same size as my St7E CCD chip.
Instrument: 12.5" f/5 Home made Newtonian Platform: Astrophysics 1200 QMD CCD Camera: SBIG ST7E w/Enhanced Cooling Exposure: LRGB = 30:10:10:18 (RGB Binned 2x2) Filters: RGB Tricolor Location: Payson, Arizona Elevation: 5150 ft. Sky: Seeing FMHW = 2.5 arcsec, Transparency 8/10 Outside Temperature: 0 C CCD Temperature: -35 C Processing: Maxim DL, Photoshop, AIP4WIN, PW Pro.
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