Wikipedia-

IC 443 (also known as the Jellyfish Nebula and Sharpless 248 (Sh2-248) is a galactic supernova remnant (SNR) in the constellation Gemini. On the plane of the sky, it is located near the star Eta Geminorum (formally named Propus) on the right.

Its distance is roughly 5,000 light years from Earth.

IC 443 may be the remains of a supernova that occurred 3,000 - 30,000 years ago. The same supernova event likely created the neutron star CXOU J061705.3+222127, the collapsed remnant of the stellar core. IC 443 is one of the best-studied cases of supernova remnants interacting with surrounding molecular clouds.

Above IC443 is reflection nebula IC444 (LBN 844). Because narrow band filters were used to acquire this image, the blue reflection portion is faint but can be seen.

Location & Date	Backyard, Abbott Observatory- Long Island, NY,  Dec. 19-21, 2023
Telescope	Askar FRA400 F/5.5 Quintuplet Petzval Astrograph, ZWO focuser, iOptron GEM45G mount Image scale 1.93 arcsec/pixel
Camera	Player One Poseidon-M Pro Antlia  Ha (4.5nm) & SII OIII 3nm Pro filters Sensor temp -15°C
Exposures	Ha-18x5m SII-18x5m OIII-24x5m Bin 1x1  Gain=0 Offset=20
Planning & Acquisition	Sequence Generator Pro
Processing	Astro Pixel Processor - calibration, stacking Photoshop  2024 - HSO combine RC-Astro- Star xTerminator, Noise xTerminator

Initial stretch of 1 1/2 hours of Hydrogen Alpha (Ha) taken with Antlia 4.5nm filter.

The spike on the bright star Propus was due to the pickoff mirror of the OAG. I moved the mirror up a little and that eliminated the spike.

Initial stretch of 1 1/2 hours of Sulfur (SII) taken with Antlia 3nm filter

Initial stretch of 2 hours of Oxygen (OIII) taken with Antlia 3nm filter