Hemisphere:  Northern  ·  Constellation: Cassiopeia (Cas)  ·  Contains:  IC 1590  ·  NGC 281
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NGC 281 the Pacman Nebula in Cassiopeia, 



    
        

            Mark Wetzel
NGC 281 the Pacman Nebula in Cassiopeia
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NGC 281 the Pacman Nebula in Cassiopeia

Getting plate-solving status, please wait...
NGC 281 the Pacman Nebula in Cassiopeia, 



    
        

            Mark Wetzel
NGC 281 the Pacman Nebula in Cassiopeia
Powered byPixInsight

NGC 281 the Pacman Nebula in Cassiopeia

Technical card

Imaging telescopes or lenses: Celestron C9.25 Edge HD

Imaging cameras: ZWO ASI 1600MM-Pro Cool

Mounts: Celestron CGEMⅡ

Guiding telescopes or lenses: Celestron C9.25 Edge HD

Guiding cameras: ZWO 174MM Mini

Focal reducers: Celestron 0.7x Focal Reducer

Software: Main Sequence Software Seqence Generator Pro 3  ·  Pleiades Astrophoto PinInsight  ·  Adobe Photoshop CC 2021 Photoshop 2021

Filters: ZWO 36mm 7nm SII  ·  ZWO 36mm 7nm OIII

Accessory: Celestron OAG


Dates:Nov. 20, 2020Nov. 21, 2020Nov. 25, 2020

Frames:
ZWO 36mm 7nm Ha: 95x300" (7h 55') (gain: 139.00) -10C bin 1x1
ZWO 36mm 7nm OIII: 97x300" (8h 5') (gain: 139.00) -10C bin 1x1
ZWO 36mm 7nm SII: 92x300" (7h 40') (gain: 139.00) -10C bin 1x1

Integration: 23h 40'

Darks: ~50

Flats: ~50

Flat darks: ~50

Avg. Moon age: 7.61 days

Avg. Moon phase: 51.86%

Bortle Dark-Sky Scale: 6.00


Basic astrometry details

Astrometry.net job: 4140299

RA center: 0h 52' 52"

DEC center: +56° 35' 31"

Pixel scale: 0.880 arcsec/pixel

Orientation: 48.872 degrees

Field radius: 0.367 degrees


Resolution: 2400x1800

Locations: Mesa, Mesa, AZ, United States

Data source: Traveller

Description

The large emission nebula, NGC 281 is a classic narrowband imaging target. The Pacman Nebula was captured with narrowband filters, Hydrogen-alpha (Ha), Oxygen-III (OIII) and Sulfur-II (SII). I captured large numbers of subframes for each channel over 5 nights. This is a false color image uses the classic Hubble pallet, mapping SII to Red, Ha to Green and OIII to Blue channels.

NGC 281 is a large emission nebula in the constellation Cassiopeia. Astronomers, possessing a vivid imagination, named it after the 1970’s Pacman video game. This nebula has strong signals in Ha, OIII and SII. NGC 281 is about 41.5 light years across, and it is about 10,000 light years from Earth (SkySafari Pro). There are striking dust lanes, with Pacman’s mouth being most prominent. There are also a few Bok Globules where new stars may be forming. There is an open star cluster in the center, IC 1590. The bright star in the center, HD 5005, is actually member of a stable quintuple system.

In previous image processing sessions, I could not get the colors right using the Hubble Pallet. A YouTube video on the channel “Entering into Space” described how to use the ColorMask script and the CurvesTransformation tool in PixInsight to change the color balance and saturation in different regions of the nebula. I was able to bring out the blues to make a rather pleasing image.

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