Wide-field Comet 17p Holmes | Todd Vance

Todd Vance
Location of photo
Millersville, MD
Date/Time of photo
11/30/2007 at 7:42pm EST
Canon EOS Digital Rebel XTi ISO 1600, 300mm zoom lens, F/8, 13 30-second exposures stacked with MLUnsold's ImagePlus, piggybacked on a Celestron CG-5 goto mount.
Last Friday I went to a star party with Howard Astronomical League in Maryland and braved the cold air to see what was out there, and got a medium field photo (a few degrees) of the comet. Mirfak (Alpha Persei) is to the left. Note the nucleus and that the comet has a tail. The entire halo filled a good portion of my 1.5 degree FOV eyepiece (Williams Optics "Swan" 2in 72 degree AFOV, 25mm at 48x on the 1200mm focal length Celestron C6-R 6in refractor) so it's about 3/4 of a degree in diameter, bigger than the full moon. In actual size, the tenuous halo is actually bigger than the sun. Too bad it doesn't cross Earth's orbit, or we'd have a pretty nice meteor shower from it.