NGC 281


18 ноября


NGC 281 is an H II region in the constellation of Cassiopeia and part of the Perseus Spiral Arm. It includes the open cluster IC 1590, the multiple star HD 5005, and several Bok globules. Colloquially, NGC 281 is also known as the Pacman Nebula for its resemblance to the video game character.

The nebula was discovered in August 1883 by E. E. Barnard, who described it as “a large faint nebula, very diffuse.” The multiple star HD 5005, also called \beta1, was discovered by S. W. Burnham. It consists of an 8th-magnitude primary with four companions at distances between 1.4 and 15.7 seconds of arc. There has been no appreciable change in this quintuple system since the first measurements were made in 1875.

Imaging telescopes or lenses: TS Optics APO65Q – 65mm f/6.5 Quadruplet Astrographe
Imaging cameras: Atik 314L+ Mono
Mounts: SW HEQ5 Pro Goto
Guiding telescopes or lenses: Chercheur 50mm
Guiding cameras: I-Nova PLA-M
Software: Pixinsight Core 1.8
Filters: Baader OIII 8.5nm 1.25″, Baader Ha 1.25″ Filter 7nm
Resolution: 1341×987
Dates: Oct. 26, 2014, Oct. 31, 2014, Nov. 1, 2014
Baader Ha 1.25″ Filter 7nm: 13×1200″ -10C bin 1×1
Baader OIII 8.5nm 1.25″: 9×1200″ -10C bin 2×2
Integration: 7.3 hours
Darks: ~21
Flats: ~7
Bias: ~101
Avg. Moon age: 5.88 days
Avg. Moon phase: 37.77%
Bortle Dark-Sky Scale: 8.00
Temperature: 12.00
RA center: 13.247 degrees
DEC center: 56.654 degrees
Orientation: -92.640 degrees
Field radius: 0.728 degrees

Аuthor: Dieter333

Аstrophotography of the day of  SPONLI, 18.11.2014