Bow-Tie Nebula
NGC 40, Caldwell 2 · Planetary nebula in Cepheus
- Magnitude
- 11.6
- Size
- 0.8′ × 0.6′
- Effective surface brightness
- 21.0 mag/arcsec²
- Best months
- Sep, Oct, Nov
- Declination
- +73°
- Filter
- Dual-band recommended
A red-tinged planetary near the pole with a bright central star. Small; dual-band brings out the bow.
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 | 20 px | 16 min99 subs | 18 min109 subs | 26 min156 subs |
| ZWO Seestar S50 Pro10 s subs, dual-band | 21 px | 18 min110 subs | 20 min122 subs | 29 min172 subs |
| ZWO Seestar S3010 s subs, dual-band | 12 px | 19 min113 subs | 21 min124 subs | 28 min170 subs |
| ZWO Seestar S30 Pro10 s subs, dual-band | 13 px | 20 min119 subs | 22 min131 subs | 30 min183 subs |
| DwarfLab DWARF 315 s subs, dual-band | 17 px | 21 min84 subs | 24 min95 subs | 36 min143 subs |
| DwarfLab DWARF mini15 s subs, dual-band | 12 px | 16 min65 subs | 18 min72 subs | 26 min103 subs |
| DwarfLab Draco30 s subs, dual-band | 33 px | 15 min30 subs | 15 min30 subs | 21 min42 subs |
| DwarfLab DWARF II15 s subs | 16 px | 51 min206 subs | 1 h 07 min270 subs | 2 h 17 min550 subs |
| Vaonis Vespera II10 s subs | 20 px | 13 min79 subs | 19 min113 subs | 44 min264 subs |
| Vaonis Vespera Pro10 s subs | 29 px | 31 min185 subs | 43 min257 subs | 1 h 36 min575 subs |
| Vaonis Vespera 310 s subs | 20 px | 12 min75 subs | 18 min108 subs | 42 min253 subs |
| Vaonis Vespera Pro 210 s subs | 29 px | 29 min175 subs | 41 min245 subs | 1 h 32 min550 subs |
| Unistellar eQuinox 24 s subs | 36 px | 15 min223 subs | 18 min277 subs | 34 min512 subs |
| Unistellar Odyssey4 s subs | 51 px | 1 h 15 min1,126 subs | 1 h 28 min1,321 subs | 2 h 25 min2,177 subs |
| Celestron Origin10 s subs | 32 px | 5 min30 subs | 5 min30 subs | 12 min73 subs |
| Celestron Origin Mark II10 s subs | 39 px | 5 min30 subs | 7 min40 subs | 17 min102 subs |
Imaging the planetary nebula
Planetary nebulae are small but intensely bright per pixel in OIII and H-alpha, so they respond very well to a dual-band filter and do not need much time for the main shell. The faint outer halos most of them have are a different proposition and need hours. Keep subs short if the central region saturates.
Per-telescope pages
- How long to image the Bow-Tie Nebula with the ZWO Seestar S50
- How long to image the Bow-Tie Nebula with the ZWO Seestar S50 Pro
- How long to image the Bow-Tie Nebula with the ZWO Seestar S30
- How long to image the Bow-Tie Nebula with the ZWO Seestar S30 Pro
- How long to image the Bow-Tie Nebula with the DwarfLab DWARF 3
- How long to image the Bow-Tie Nebula with the DwarfLab DWARF mini
- How long to image the Bow-Tie Nebula with the DwarfLab Draco
- How long to image the Bow-Tie Nebula with the DwarfLab DWARF II
- How long to image the Bow-Tie Nebula with the Vaonis Vespera II
- How long to image the Bow-Tie Nebula with the Vaonis Vespera Pro
- How long to image the Bow-Tie Nebula with the Vaonis Vespera 3
- How long to image the Bow-Tie Nebula with the Vaonis Vespera Pro 2
- How long to image the Bow-Tie Nebula with the Unistellar eQuinox 2
- How long to image the Bow-Tie Nebula with the Unistellar Odyssey
- How long to image the Bow-Tie Nebula with the Celestron Origin
- How long to image the Bow-Tie Nebula with the Celestron Origin Mark II