The Jellyfish Nebula (IC 443)

A supernova remnant in Gemini, the Jellyfish Nebula is the ghostly aftermath of a stellar explosion that occurred between 3,000 and 30,000 years ago — its tangled filaments still expanding outward through space.

IC 443 sits around 5,000 light-years away in the constellation Gemini, and is one of the most studied supernova remnants in the sky. Unlike many nebulae which are powered by ongoing star formation, the Jellyfish is a relic — the expanding shockwave from a single catastrophic stellar death, still colliding with surrounding molecular clouds thousands of years later.

At its heart lies a neutron star, the compressed core left behind after the explosion. The interaction between the expanding remnant and the surrounding interstellar medium creates the complex, filamentary structures that give this nebula its distinctive shape.

The Jellyfish is a challenging narrowband target — the signal is fainter than objects like the Orion or Rosette nebulae, and the structure is complex enough that processing requires care to bring out the filaments without introducing artefacts. It rewards patience.