NGC925 - Spiral Galaxy in Triangulum
with 10" f/3.9 Astrograph
Uploaded 11/5/16

This bright 10.7 magnitude inclined spiral has quite low surface brightness, and is a challenge to image. About 11 arc minutes long, this is the second best galaxy in Triangulum to grab some detail on after M33. I have shot this many times with the 12 inch, but this image is equal to those past shots in magnitude limit and exceeds in revealing the faint outer details due its much faster primary mirror.

The galaxy sports some superb pink HII regions and many knots in the spiral arms. Two images are posted here from the same data set, which took one hour and a half. The top image is the normal shot, showing the full field of the 10 inch and many colorful foreground stars. The second image is a negative photo key, showing not only many very faint background galaxies - all circled in red ranging in brightness from 17.8 to 19.0 or so. The faintest stars in this image are 20.0. Also, three asteroids are indicated with ovals on their trails (they all move about the same amount in an hour), the designation for the object - none have been named yet - and the magnitude according to the latest orbital elements for each object. Surprisingly, the faintest asteroid is mag 19.4 and only seen as a very dim streak on the largest images. If I can figure out how to track them and combine their light, the magnitude limit would certainly be near 20.

Select an image size for a larger view: 1290 x 960 1600 x 1200
Select an image size for a larger view: 1290 x 960
Instrument: 10" f/3.9 Orion Astrograph Newtonian with Baader MPCC Mount: Astrophysics 1200 QMD CCD Camera: SBIG 10XME NABG with Enhanced Water Cooling Guider: Meade DSI Pro w/80mm piggyback refractor Exposure: LRGB = 60:10:10:10 AstroDon RGB Combine Ratio: 1: 1.05: 1.2 Location: Payson, Arizona, Elevation: 5150 ft. Sky: Seeing FWHM = 3 arcsec , Transparency 9/10 Outside Temperature: 45 F CCD Temperature: -20 C Image Processing Tools: Maxim DL6: Calibration, deblooming (Starizona Debloomer), aligning, stacking PixInsight: Curves, Deconvolution Photoshop CS2: Curves, Color Correction, Gradient removal (Grad Xterminator), Cleanup HOME GALAXIES EMISSION NEBS REFLECTION NEBS COMETS GLOBULARS OPEN CLUST PLANETARIES LINKS