IC 4628 is another active star-forming region that is not very often imaged. Its relative faintness and its proximity to NGC 6334 and NGC 6188 makes it an overlooked nebula, despite its beauty. In fact, this nebula is not included in the NGC catalog and it is also known as Gum 56 (it was catalogued by the Australian astronomer Colin S. Gum). The popular name of “Prawn Nebula” is due to two areas in it that vaguely resemble this tasty crustacean.
The image also includes three open clusters: NGC 6231, just right of the lower center, NGC 6242, at the upper center and NGC 6268, on the left, very near the upper left corner. This image has been taken with narrowband filters and mapped to natural color, in a way that tries to mimic the visible spectrum of this nebula.
Name(s): IC 4628. The Prawn Nebula
Type: Emission Nebula
RA: 16h 56m 54s
Dec: -40º 30’ 53”
Size (arcmin): 90×60
Distance: 6,000 ly
Date: 2017-07-23 thru 2017-07-28
Location: iTelescope.net, SSO near Coonabarabran, NSW Australia
Size (arcmin): 165×168
Telescope: Takahashi TOA 130 f/5.7
Camera: SBIG STX16803 (4096x4096pix)
Guiding: Astrodon MonsterMOAG off-axis guider
Total exposure: 14.6 hours (Ha: 7h 20m; OIII: 4h; SII: 2h 40m; RGB: 36m)
Processing: CCDStack, Photoshop CC 2018