Messier 2 or M2 (also designated NGC 7089) is a globular cluster in the constellation Aquarius, five degrees north of the star Beta Aquarii and it is one of the largest known globular clusters.
M2 is, under extremely good conditions, just visible to the naked eye. Binoculars or a small telescope will identify this cluster as non-stellar, while larger telescopes will resolve individual stars, of which the brightest are of apparent magnitude 13.1.
M2 is about 37,500 light-years distant from Earth. At 175 light-years in diameter, it is one of the larger globular clusters known. The cluster is rich, compact, and significantly elliptical. It is 13 billion years old and one of the older globulars associated with the Milky Way Galaxy.
M2 contains about 150,000 stars, including 21 known variable stars. Its brightest stars are red and yellow giant stars.
Imaging Telescope: Vixen ED81s f/7.7
Mount: Skywatcher HEQ5 Synscan Pro (belt mod)
Camera: QHY 533M
Filter Wheel: QHY CFW3S-SR
Filters: L,R,G,B
Guiding camera: ZWO ASI120MM Mini (mono)
Guidescope: SkyWatcher EvoGuide 50ED
Constellation: Andromeda
Date: 14-15 August-2023
Location: Korinthos - Greece - Albireo Observatory 1
Sky brightness: B7
Exposure Time:
L: 12x120 sec (gain: 56.00, offset: 12.00) 0°C bin 1×1
R: 12x120 sec (gain: 56.00, offset: 12.00) 0°C bin 1×1
G: 12x120 sec (gain: 56.00, offset: 12.00) 0°C bin 1×1
B: 12x120 sec (gain: 56.00, offset: 12.00) 0°C bin 1×1
Calibration Frames: Darks, Flats, Dark Flats
Acquisition: ACP Expert, MaximDL
Processing: Pixinsight, Photoshop
