The Crab Nebula is a supernova remnant that has an apparent magnitude of 8.4 and lies about 6,500 light-years away in the constellation Taurus. Corresponding to a bright supernova recorded by Arab, Chinese and Japanese astronomers in 1054, this nebula was observed by John Bevis in 1731 and was recorded as the first Messier object catalogued in 1758. Some catalogue designations for the Crab Nebula are M1 (Messier 1), NGC 1952, Taurus A, Sharpless 244 (Sh2-244) and LBN 833.
This image was created using narrowband data where the emission lines were assigned to the color channels to mimic natural colors. We used the technique outlined by Richard Crisp where 100% H-alpha + 33% SII = red, 100% OIII = green, & 100% OIII + 33% H-alpha = blue.
Telescope: Celestron 8” EdgeHD @ f/10
Accessories: Dew control by Dew Buster
Mount: Takahashi EM-200 Temma2
Camera: QSI583wsg CCD @ -10.0C
Guiding: Starlight Xpress Lodestar via PHD
Filters: Astrodon 5nm Ha, OIII, SII
Exposure: 8 x 30min.(Ha); 8 x 30min.(OIII); 8 x 30min.(SII); all frames binned 1x1
Acquisition: ImagesPlus Camera Control v5.0
Processing: Calibration, DDP in ImagesPlus 5.0; Registration in RegiStar
Post-processing: ImagesPlus 5.0; Adobe Photoshop CS5; Gradient Xterminator, Noise Ninja
Date(s): November 25, 2012; December 11, 12, 13, 2012
Temperature (begin - end): N1:41.7ºF – 36.5ºF; N2:31.5ºF – 26.1ºF; N3:37.9ºF – 28.8ºF; N4:37.0ºF – 30.6ºF
Capture conditions: N1 - transparency: Above Avg 4/5; seeing: Poor 2/5; N2 - transparency: Above Avg 4/5; seeing: Avg 3/5; N3 - transparency: Above avg 4/5; seeing: Avg 3/5; N4 - transparency: Above Avg 4/5; seeing: Excellent 5/5
Location: Hendersonville, TN, USA