Messier 12 or M 12 (also designated NGC 6218) is a globular cluster in the constellation of Ophiuchus. It was discovered by the French astronomer Charles Messier on May 30, 1764, who described it as a “nebula without stars”. In dark conditions this cluster can be faintly seen with a pair of binoculars. Resolving the stellar components requires a telescope with an aperture of 8 in (20 cm) or greater. In a 10 in (25 cm) scope, the granular core shows a diameter of 3′ (arcminutes) surrounded by a 10′ halo of stars.
Object Designations: M12 or NGC 6218
Also known as:
Constellation: Ophiuchus
Object Type: Starburst cluster
Distance: 16 kilo light-years away
Magnitude: 6.7
Discovery: Charles Messier in 1764
This final image is:
20 – 30 second subs at 100 gain – no filter – 10 minutes of integration
I processed the images using Pixinsight using:
Blink to clear out low quality images
Weighted Batch Balance
SpectroPhotometricCalibration
AutomaticBackgroundExtractor
BlurExterminator
NoiseExterminator
GeneralizedHyperbolicStrectch
ColorCalibration on both versions
StarXTerminator
Curves on both versions using other version as mask
Pixmath to put stars back with both images.
