by Craig and Tammy Temple
NGC 2403 is a magnitude 8.90 spiral galaxy approximately 8 million light years distant in the constellation Camelopardalis. Noteworthy is its H II nucleus. Discovered in 1788 by William Herschel, NGC 2403 is a distant member of the M81 Group. Visible in this image is supernova SN 2004dj, discovered by Koichi Itagaki on July 31, 2004.
Telescope: Celestron C8 Schmidt-Cassegrain
Accessories: Celestron f/6.3 reducer/corrector; Dew control by Dew Buster®
Mount: Orion Atlas EQ-G controlled by EQMOD
Guiding: Orion StarShoot AutoGuider on William Optics ZS66
Camera: Canon Digital Rebel T1i, Hap Griffin Baader modified
Filters: Astronomik CLS-CCD EOS Clip
Exposure: 93 x 300sec @ ISO 800 (7hr. 45min.)
Acquisition: ImagesPlus 3.82 Camera Control
Processing: ImagesPlus 3.80a – Calibrated, registered, averaged, DDP
Post-processing: Adobe Photoshop CS4; Gradient XTerminator; Noise Ninja; Noel Carboni's Tools
Date(s): March 26, 30 & 31, 2010
Temperature(s): N1:48ºF (dropped to 45ºF); N2:59ºF (dropped to 52ºF); N3:70ºF (dropped to 63ºF)
SQM reading (begin - end): N1:17.12 - 17.23; N2:18.49 - 18.25; N3:18.64 - 18.50
Moon data: N1: 88% illuminated, 59º angular separation; N2: 98% illuminated, 101º angular separation; N3: 94% illuminated, 111º angular separation