M81 in Ursa Major


Copyright 2007 Hap Griffin

M81, also known as Bode's Galaxy, is a spectacular example of what is known as a "grand design" spiral galaxy.  It's prominent spiral structure with rich star forming regions, showing here as blue due to the abundance of hot young stars, is a result of a strong gravitational influence with another nearby spiral galaxy, M82.

If your monitor is correctly adjusted, you should be able to make out a faint bluish smudge to the left of the galaxy.  This is M81's satellite, the irregular galaxy Holmberg IX...very faint at magnitude 16.5 and rarely imaged.  

M81 lies at a distance of 12 million light-years.

Date/Location:    December 5, 2007     Griffin/Hunter Observatory    Bethune, SC
Instrument:    Canon 40D Digital SLR (modified) through F/4.7 10" Newtonian w/ Baader MPCC 
Focal Ratio:   F/4.7
Guiding:    Auto via Orion ED-80 w/ SBIG ST-237
Conditions:    Mostly clear with passing clouds
Weather:    35 deg. F 
Exposure: 256 minutes total @ ISO 800 (86 x 3 min exposures)
Filters:    Baader UV/IR Block internal to camera
Processing:    Focused and captured with Breeze Systems DSLRControl Pro.  RAW to TIFF conversion, frame calibration, alignment and stacking, Digital Development, Adaptive Richardson_Lucy deconvolution, scaling and JPEG conversion with ImagesPlus v3.  Tweaking with Photoshop CS2.