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).

Sixty-one 3-minute exposures and twenty 60-second exposures (204 minutes total exposure) at ISO 800 taken on August 31 / September 1 and on September 3 / 4, 2019 were added for this shot with the DeepSkyStacker software and the final image processing was done in Photoshop. A large percentage of the exposures showed a slight blur due to focusing errors and / or a tendency towards star trails due to tracking errors. Under ideal circumstances, a total exposure time of one hour should show a similar or better result.

Equipment: Canon EOS 450D Baader modified camera, 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", www.siaris.net. Map is slightly modified. The map can be downloaded here.