Nightscapes & Deep Sky Colors

Astrophotography Brian A. Morganti

IC 443 Jellyfish Nebula

IC444 - vDB75 - Sh2-249


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The Jellyfish Nebula is the remnant of a supernova in the constellation of Gemini.  Energetic shock waves from the supernova excite hydrogen within the molecular cloud, creating lattice-like filaments of luminosity.  The combined magnitude of the nebula is +3.7 and is near the bright star Eta Geminorum (Propus), a  spectroscopic binary with the primary star being a semi-irregular variable (3.15 to 3.9 magnitude).  Eta Geminorum is a Red Giant located 350 light-years from Earth.  The bright yellow star on the left is Mu Geminorum which shines at +2.90 magnitude.

The supernova that formed IC 443 is thought to have occurred more than 30,000 years ago leaving behind a neutron star that is a pulsar. The nebula is an expanding debris cloud from that supernova explosion and is 75 light years across. 

The large expanse of red emission nebula to the upper left of the Jellyfish Nebula is Sh2-249 and the small blue reflection nebula vdB 75.  Just to the right of the blue reflection nebula can be seen the small white/yellowish patch of IC444, a combination reflection/emission nebula.  The entire area surrounding the blue refection nebula vdB 75 is the large open star cluster known as Collinder 89. 

North is up in this image.


  • Date & Location:  Feb 19, 20, 26th, 2017.  -StarEffects Observatory - Bernville, PA

  • Weather:  40F first 2 nights, 28F 3rd night..

  • Sky Conditions:  Clear with above average transparency first 2 nights, average 3rd night.

  • Optics:  TeleVue NP101is Refractor w/field flattener  =  540mm @ f5.4

  • Filter:  Astronomic  EOS clip-in CLS-CCD (Light Pollution Suppression)

  • Mount:  AP900GTO

  • Guiding:  TV60is w/Orion SSAG @ 5 second exposures - Very Good Graph

  • Camera:  Canon 6DH Hutech Modified - Baader UV/IR

  • Exposure:  26 x 6 min / 14 x 6 min / 25 x 6min / ISO 800 (6  hours 30 min total)

  • Calibration Frames:  16 Darks & 9 Bias frames + 10 flat field images acquired with Alnitak Flat Man.

  • Processing:  Images Plus 5.75a, Photoshop CS6, NIK tools, Carboni Actions Tools

  • Comments:   Images from first two nights were calibrated separately from last night of imaging due to large temperature spread, then combined before final processing using IP layer mask tool to enhance nebula seperate from stars. 


Image below from previous attempt in 2009

click on image for a larger version



  • Date & Location:  December 18, 2009 (early am) - Bernville, PA

  • Weather:  Calm wind, 22F.

  • Sky Conditions:  Scattered Cirrus with above average transparency.  . 

  • Optics:  TeleVue NP101is Refractor with 0.8x TeleVue Reducer = 432mm @ f4.3

  • Filter:  Astronomic  EOS clip-in CLS-CCD (Light Pollution Suppression)

  • Mount:  Losmandy G-11 equatorial with Gemini V4

  • Guiding:  Orion Solitaire w/TeleVue TV60is

  • Camera:  Canon T1i (500D) Hap Griffin Modified - Baader UV/IR

  • Exposure:  69 min (8 x 8 min, 1 x 5 min) @ ISO 800 RAW

  • Calibration Frames:  No dark frame subtraction (22F)

  • Processing:  Photoshop CS4, Noise Ninja, GradientXTerminator, NIK.

  • Comments:  Overall I'm rather pleased with this image.  Some of the light frames were captured between the cirrus clouds with above average transparency and no doubt helped enhance some details of the fainter nebulosity.  



Astrophotography  -  Nightscapes & Deep Sky Colors