by Craig and Tammy Temple
M109 (NGC3992) is a magnitude 10.60 barred spiral galaxy that is approximately 46 million light years distant in the constellation Ursa Major. It was discovered in 1781 by Pierre Méchain, and again in 1783 by Charles Messier when he added it as entry number 109 in his famous catalog.
Telescope: Celestron C8 Schmidt-Cassegrain
Accessories: Celestron f/6.3 reducer/corrector
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: 122 x 300sec @ ISO 800 (10hr. 15min.)
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 4 & 5, 2010
Temperature(s): N1:41ºF (dropped to 36ºF); N2:41ºF (dropped to 31ºF)
SQM reading (begin - end): N1:18.45 - 18.90; N2:18.32 - 19.17