Jellyfish Nebula
IC 443, Sh2-248 · Supernova remnant in Gemini
- Magnitude
- 12.0
- Size
- 50′ × 40′
- Effective surface brightness
- 23.0 mag/arcsec²
- Best months
- Dec, Jan, Feb
- Declination
- +23°
- Filter
- Dual-band recommended
A supernova remnant beside Propus in Gemini, with a bright rim like a jellyfish bell. Faint; dual-band and hours.
Reachable from mid-northern latitudes (UK, northern US, central Europe) and from the south.
How long with each smart telescope
| Telescope | In frame | Bortle 3 (rural) | Bortle 5 (suburban) | Bortle 7 (urban edge) |
|---|---|---|---|---|
| ZWO Seestar S5010 s subs, dual-band | 1.2× frame | 2 h 42 min970 subs | 3 h 13 min1,157 subs | 5 h 29 min1,975 subs |
| ZWO Seestar S50 Pro10 s subs, dual-band | 60% | 3 h 05 min1,111 subs | 3 h 39 min1,314 subs | 6 h 06 min2,198 subs |
| ZWO Seestar S3010 s subs, dual-band | 70% | 3 h 24 min1,227 subs | 3 h 56 min1,414 subs | 6 h 12 min2,232 subs |
| ZWO Seestar S30 Pro10 s subs, dual-band | 37% | 3 h 22 min1,214 subs | 3 h 58 min1,427 subs | 6 h 33 min2,357 subs |
| DwarfLab DWARF 315 s subs, dual-band | 51% | 2 h 51 min686 subs | 3 h 40 min879 subs | 7 h 10 min1,721 subs |
| DwarfLab DWARF mini15 s subs, dual-band | 70% | 2 h 38 min631 subs | 3 h 09 min756 subs | 5 h 25 min1,301 subs |
| DwarfLab Draco30 s subs, dual-band | 67% | 2 h 04 min248 subs | 2 h 30 min300 subs | 4 h 23 min527 subs |
| DwarfLab DWARF II15 s subs | 46% | 11 h2,645 subs | 16 h3,777 subs | 36 h8,722 subs |
| Vaonis Vespera II10 s subs | 58% | 2 h 22 min850 subs | 4 h 03 min1,461 subs | 11 h4,131 subs |
| Vaonis Vespera Pro10 s subs | 51% | 5 h 54 min2,127 subs | 9 h 28 min3,411 subs | 25 h9,026 subs |
| Vaonis Vespera 310 s subs | 57% | 2 h 14 min803 subs | 3 h 52 min1,390 subs | 11 h3,955 subs |
| Vaonis Vespera Pro 210 s subs | 50% | 5 h 34 min2,002 subs | 8 h 59 min3,236 subs | 24 h8,629 subs |
| Unistellar eQuinox 24 s subs | 1.5× frame | 3 h 26 min3,096 subs | 4 h 30 min4,048 subs | 9 h 07 min8,209 subs |
| Unistellar Odyssey4 s subs | 1.5× frame | 19 h16,852 subs | 23 h20,316 subs | 39 h35,457 subs |
| Celestron Origin10 s subs | Only just | 32 min194 subs | 1 h 01 min367 subs | 3 h 07 min1,125 subs |
| Celestron Origin Mark II10 s subs | 1.1× frame | 39 min234 subs | 1 h 20 min483 subs | 4 h 22 min1,574 subs |
Imaging the supernova remnant
Supernova remnants are emission-line objects, strong in both hydrogen-alpha and OIII, and their filaments are thin, so pixel scale matters as much as aperture. A dual-band filter is essential from any lit sky and still helps under a dark one. These are long-integration targets; plan on several sessions and stack across nights.
Per-telescope pages
- How long to image the Jellyfish Nebula with the ZWO Seestar S50
- How long to image the Jellyfish Nebula with the ZWO Seestar S50 Pro
- How long to image the Jellyfish Nebula with the ZWO Seestar S30
- How long to image the Jellyfish Nebula with the ZWO Seestar S30 Pro
- How long to image the Jellyfish Nebula with the DwarfLab DWARF 3
- How long to image the Jellyfish Nebula with the DwarfLab DWARF mini
- How long to image the Jellyfish Nebula with the DwarfLab Draco
- How long to image the Jellyfish Nebula with the DwarfLab DWARF II
- How long to image the Jellyfish Nebula with the Vaonis Vespera II
- How long to image the Jellyfish Nebula with the Vaonis Vespera Pro
- How long to image the Jellyfish Nebula with the Vaonis Vespera 3
- How long to image the Jellyfish Nebula with the Vaonis Vespera Pro 2
- How long to image the Jellyfish Nebula with the Unistellar eQuinox 2
- How long to image the Jellyfish Nebula with the Unistellar Odyssey
- How long to image the Jellyfish Nebula with the Celestron Origin
- How long to image the Jellyfish Nebula with the Celestron Origin Mark II