Messier 2 (Aquarius)

Object image
Fig.1 - The first globular cluster to be added to the Messier catalog: Messier 2 (NGC 7089) in Aquarius, photographed with a 16-inch f/4.5 Dob on an equatorial platform.
Object name: Constellation: Coordinates: Apparent size: Visual brightness:
Messier 2 (NGC 7089) Aquarius 21h33m / -00°49' 16' 6.3 mag

The globular cluster Messier 2 (NGC 7089) in the constellation Aquarius. Messier 2 is one of the largest known globular clusters. It is about 55,000 light-years distant from Earth and 175 light-years in diameter. Messier 2 contains about 150,000 stars. It was discovered by the French astronomer Jean-Dominique Maraldi in 1746 and rediscovered by Chares Messier in 1760 (source: Wikipedia).

Seventy 1-minute exposures (70 minutes total exposure) at Gain 100 taken on August 12, 2023, were added for this shot with Astro Pixel Processor (APP) software and the final image processing was done in Photoshop. Darks, flats, darkflats and bias frames were used.

Equipment: Cooled ASI 2600MC Pro camera (-10°C), TeleVue Paracorr Type II coma corrector, 16" f/4.5 "Ninja" dobsonian telescope riding on a dual-axis Tom Osypowski equatorial platform, Lacerta MGEN autoguider, Lacerta off axis system (field of view comparison: image of the moon with the same equipment).

Search chart
Fig.2 - Search chart for Messier 2. Map © 2021 "The Mag-7 Star Atlas Project", Map is slightly modified. The map can be downloaded here.