I was going over some old files and I can't see where I have posted this one before on IIS (I did search my posts). Please let me know if I have, although in this rendition I have reworked the data using some different processing techniques to highlight the surrounding nebula
Target: NGC 6193 open star cluster in Ara
Camera: QHY 8 OSC
Scope: GSO CF RC200
EFR: WOF2 reducer f/7.2
Mount: EQ6 Pro
Exposures: 1hr in a mixture of exposures up to 15 minutes captured 16/10/2010 between 9:00 and 11:30pm
Seeing: 50% moon, slight wind, good seeing
Guiding: Orion Starshoot Autoguider using PHD with ED80
Focus: Focus Bahtinov mask
Stacking: DSS with flats and bias, no darks
Processing: PS CS3
Dreyer's description: Cl, vL, lRi, lC, rrr, F neb inv Cross Identifications: GC 4225, h 3642, Dun 413. . Right Ascension: 16 : 41.3 (hours : minutes) Declination: -48 : 46 (degrees : minutes) Apparent Magnitude: 5.2 Apparent Diameter: 15. (arc minutes)
NGC 6193 is a large open star cluster in the constellation of Ara (the Altar). It is located about 3800 light-years away from our Solar System and it is unusually rich in close binary, or double, stars. This open cluster is also home to a large number of newly born hot stars.
NGC 6193, embedded in a region of dense gas clouds and obscuring lanes of dust, comprises the core of the Ara OB association with its scorching young stars. Intense ultraviolet light streams from the hottest stars in the cluster — two closely spaced O-type stars, catalogued as HD 150135 and HD 150136 — heating up and illuminating their gaseous surroundings, and thus making it shine brightly. Some of these binary systems engage in extremely violent behaviour, at least in terms of radiation production, as the powerful stellar winds from these tightly bound stars collide and produce energetic X-ray emissions
