M106 Spiral Galaxy and NGC4217

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2013/03/13 - A lot of things went wrong while shooting this object. My flatfieldpanel broke down, I had USB issues with the ASA mount and CCDAutoPilot decided to guide on a hot pixel again. I could resolve all issues, but I lost valuable clear sky time.

A second session on this object went without problems and I was able to shoot the necessary data, more detail is present now.

Messier 106 (also known as a bright star) is a spiral galaxy in the constellation Canes Venatici. It was discovered by Pierre Méchain in 1781. M106 is at a distance of about 22 to 25 million light-years away from Earth. It is also a Seyfert II galaxy, which means that due to x-rays and unusual emission lines detected, it is suspected that part of the galaxy is falling into a supermassive black hole in the center. NGC 4217 is a possible companion galaxy of Messier 106.

M106 has a water vapor megamaser (the equivalent of a laser operating in microwave instead of light and on a galactic scale) that is seen by the 22-GHz line of ortho-H2O that evidences dense and warm molecular gas. Water masers are useful to observe nuclear accretion disks in active galaxies. The water masers in M106 enabled the first case of a direct measurement of the distance to a galaxy and thereby providing an independent anchor for the cosmic distance ladder. M106 has a slightly warped, thin, almost edge-on Keplerian disk which is on a subparsec scale. It surrounds a central area with mass 4 × 107M⊙.

Object information
Name : M106 Spiral Galaxy and NGC4217
Type : Galaxy
Constellation : Canes Venatici
Distance : 23.700K light-year
Apparent dimensions : 18'.6 × 7'.2
Apparent magnitude : 9.10

Image information
Image date : 2013/03/13, 2013/03/04
Right ascension : 12:17:30.779
Declination : 47°15' 14.89"
Focal length : 1381.26 mm
Focal ratio : f/5.44
Image resolution : 0.806 arcsec/pixel
Field of view : 43' 13.3" x 31' 39.0"
Sky quality : 19.55 magnitude/square arcsecond
Sensor temperature : -30°C
Light frames : 8 hours total exposure time
15x 600 sec. luminace unbinned
11x 600 sec. RGB unbinned
Image acquisition with CCDAutoPilot and Maxim DL
Auto-guiding with Maxim DL Auto-focusing with FocusMax
Bias frames : 100x unbinned
Dark frames : None
Flat frames : 5x luminance unbinned
5x RGB unbinned
Created with Gerd Neumann Aurora flatfield panel
Processing : PixInsight for calibration (bias frames 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