Messier 81 (Ursa Major)
Fig. 1 - A 'grand design' spiral, with open, well-defined spiral arms: The galaxy Messier 81 in Ursa Major, photographed with an 8-inch f/5 Newtonian reflector on a ZWO AM5 mount.
| Object name: | Constellation: | Coordinates: | Apparent size: | Visual brightness: |
|---|---|---|---|---|
| Messier 81 (NGC3031) | Ursa Major | 09h56m / +69°04' | 26.9' x 14.1' | 6.9 mag |
The beautiful spiral galaxy Messier 81 (NGC 3031, "Bode's Galaxy") in the constellation Ursa Major. Messier 81 is the largest galaxy in the M81 Group with 34 members. Messier 81 is approximately 12 million light-years from Earth. Gravitational interactions of Messier 81 with Messier 82 and NGC 3077 have stripped hydrogen gas away from all three galaxies, forming gaseous filamentary structures in the group. Messier 81 was discovered by German astronomer Johann Elert Bode in 1774 (source: Wikipedia).
Exposure time: 4h 51min (97x3min) at gain 100 and -10°C, taken on February 2 / 3, 2025. Processing with Astro Pixel Processor (APP) and Photoshop. Darks, flats, bias and darkflats were used.
Equipment: Cooled ASI 2600MC Pro camera, TeleVue Paracorr Type II coma corrector, 8" f/5 "ONTC" Newtonian telescope riding on a ZWO AM5 Strain Wave Mount, ZWO OAG-L off axis system, ASI 174MM Mini guide camera, ASIAIR Plus.
Fig. 2 - Search chart for Messier 81. Copyright 2025 'The Mag-7 Star Atlas Project', www.siaris.net.