M81 Bode's Galaxy

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2013/02/17 - Finally the setup is working as it should. Fully automated with CCDAutoPilot, Maxim and FocusMax. There was some dew on the secondary, so I need a dew heater.

Messier 81 (also known as NGC 3031 or Bode's Galaxy) is a spiral galaxy about 12 million light-years away in the constellation Ursa Major. Due to its proximity to Earth, large size and active galactic nucleus (which harbors a 70 million M☉ supermassive black hole), Messier 81 has been studied extensively by professional astronomers. The galaxy's large size and relatively high brightness also make it a popular target for amateur astronomers.

Messier 81 was first discovered by Johann Elert Bode in 1774. Consequently, the galaxy is sometimes referred to as "Bode's Galaxy". In 1779, Pierre Méchain and Charles Messier reidentified Bode's object, which was subsequently listed in the Messier Catalogue.

Messier 81 is located approximately 10° northwest of Alpha Ursae Majoris along with several other galaxies in the Messier 81 Group. Messier 81 and Messier 82 can both be viewed easily using binoculars and small telescopes. The two objects are generally not observable to the unaided eye, although highly experienced amateur astronomers may be able to see Messier 81 under exceptional observing conditions. Telescopes with apertures of 8 inches or larger are needed to distinguish structures in the galaxy.


Object information
Name : M81 Bode's Galaxy
Type : Galaxy
Constellation : Ursa Major
Distance : 11.800K light-year
Apparent dimensions : 26.9' x 14.1'
Apparent magnitude : 6.94

Image information
Image date : 2013/02/17, 2013/02/13
Right ascension : 9:55:30.565
Declination : 69°3' 54.15"
Focal length : 1381.52 mm
Focal ratio : f/5.44
Image resolution : 0.806 arcsec/pixel
Field of view : 43' 48.3" x 32' 56.9"
Sensor temperature : -25°C
Light frames : 4 hours total exposure time
8x 600 sec. RGB unbinned
Image acquisition with CCDAutoPilot and Maxim DL
Auto-guiding with Maxim DL
Bias frames : 100x unbinned
Dark frames : Bap pixel map
Flat frames : 5x RGB unbinned
Created with Gerd Neumann Aurora flatfield panel
Processing : PixInsight for calibration (bias frames, bad pixel map and flat frames), alignment and integration.
Adobe Photoshop CS6 for final touch.

Equipment information
Telescope : Robtics 10" 2000mm f/8 Ritchey Chretien
Corrector : Astro-Physics CCDT67 Focal Reducer
Focuser : Moonlite CS Ritchey Chretien focuser with high resolution stepper motor
Mount : ASA DDM60 Pro direct drive german equatorial mount controlled with AutoSlew
Camera : QSI 683wsg-8 cooled CCD camera with Kodak KAF-8300 sensor and Off Axis Guide (OAG) port
Guidecamera : Starlight Xpress Lodestar autoguider
Filters : Astrodon Tru-Balance E-Series LRGB & Astrodon 3nm H-α, 3nm O-III, 3nm S-II and 3nm N-II
Observatory site : Etten-Leur, The Netherlands