Jellyfish Nebula (IC 443)
The wreck of a star that exploded in Gemini, still running into a cold cloud beside it. It sits 0.4° from Propus, a star bright enough to see from town.
Supernova remnant in Gemini.
Can you see it from Guyana?
From Georgetown (6.8° N) it climbs to 74° above the northern horizon at its highest; from Lethem (3.4° N), to 71° above the northern horizon. It is highest at midnight on the night of 23 Dec, in the middle of its season. The page works out tonight's rise, highest point and set for both towns in Guyana time (UTC-4), and where the Moon is.
What you'll see
- Your eyes: Not visible to the eye. It lies 0.4° east of Propus.
- 10x50 binoculars: Not visible in binoculars.
- A small telescope (80 to 100 mm): Very hard visually: an OIII filter and low power show a faint arc near Propus.
- A camera: Spans about 40% of an APS-C frame at 600 mm (field 2.2° × 1.5°); needs a tracking mount. An H-alpha-sensitive (modified) camera brings out its red glow.
How big, how bright, how far
- Size on the sky: 50′ × 40′, 1.6 Moons across (the Moon is about 31′ wide).
- Distance: 5,190 light-years. The light reaching your eye left it about 5,190 years ago.
- True size: 76 light-years across its catalogued outline; light crosses it in 76 years.
Apparent size from OpenNGC (Mattia Verga), CC-BY-SA-4.0.
What it is made of
- Type
- Supernova remnant
What is in it, not measured:
- Gas shocked by a supernova blast wave
- Debris of the star that exploded
- The cold cloud: the blast is running into
How we know: Distance from Gaia distances to the stars in front of and behind the cloud it is running into: Zucker et al. 2020, A&A 633, A51 (2020A&A...633A..51Z, via SIMBAD mesDistance): 1,592 (-18.0/+27.0) pc, retrieved 2026-10-21. True size: the apparent size times the distance (apparent size: OpenNGC (Mattia Verga, CC BY-SA 4.0), commit 4e2398a2).
More deep-sky objects: Crab Nebula (M1) · Veil Nebula (NGC 6960, 6992, etc.) · Monkey Head Nebula (NGC 2174) · Open Cluster M35 · Open Cluster M37 · Christmas Tree Cluster & Cone Nebula (NGC 2264)