• NGC 6218 or Messier 12, a globular in Ophiuchus
    • M12 globular
    M12 annotated
  • NGC 6218, M12, is a small globular cluster
  • located in the constellation Ophiuchus.
  • In dark skies, it can be seen in binoculars.
  • M12 has lost a significant number of its low mass
  • stars during its orbit around the galactic center.
  • M12 is 16.4 kly from us.
  • Hover over the picture for an annotated version
  • Date:  20 April 2026
  • FOV:  approximately 45' × 30'; the apparent size of M12 is about 16'
  • Rotation:  0.002°
  • 8 May, 2026:
  • Telescope:  Orion Apex 127mm Mak-Cass (1382mm,
  • nominally 1540mm, f/12.1)
  • Guiding:  ZWO ASI120MM mini mono guide camera,
  • SVBony SV165 Mini 40mm f/4 guide scope
  • Computer:  ASIair Plus 256G
  • Mount:  ZWO AM5
  • Camera:  ZWO ASI071MC Pro Cooled (-10°C) Color CMOS, gain 90
  • Pixel size:  4.78 μm
  • Resolution:  0.713 arcsec/pixel
  • 20 April, 2026:
  • Telescope:  Stellarvue SVX102T + SFFX-1 (714mm, f/7)
  • Guiding:  ZWO ASI120MM mini mono guide camera,
  • SVBony SV165 Mini 40mm f/4 guide scope
  • Computer:  ASIair Plus
  • Mount:  ZWO AM5
  • Camera:  ZWO ASI6200MC Pro Cooled (-10°C) Color CMOS, gain 100
  • Pixel size:  3.76 μm
  • Resolution:  1.052 arcsec/pixel
  • Stacking:  sixty-seven 300 second frames using Pixinsight
  • Calibration:  20 flats, 20 dark flats, and 20 darks per session
  • Total Time:  5 hours 35 minutes
  • Processing:  Pixinsight
  • preprocessing → M12_2026April20x20 and M12_2026June08x47
  • ImageIntegration → M12_Int
  • MStr, GHS, HST, MAS, PMath MStr + MAS + GHS + HST →
  • M12_Averaged, CurvesTransformaion, Sat, DynCrop/Scale
  • Location:  Darling Hill Observatory near Vesper, NY on 20 April 2026
  • Piseco Airport, near Piseco, NY on 8 June 2026