Orion Nebula
M42, NGC 1976 · Emission nebula in Orion
- Magnitude
- 4.0
- Size
- 85′ × 60′
- Effective surface brightness
- 21.2 mag/arcsec²
- Best months
- Nov, Dec, Jan
- Declination
- -5°
- Filter
- Dual-band recommended
The brightest nebula in the northern sky and the one every smart scope gets pointed at first. The core saturates in a minute; the wings and the Running Man need real time. Mix short and long stacks.
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 | 2.0× frame | 10 min58 subs | 11 min65 subs | 16 min95 subs |
| ZWO Seestar S50 Pro10 s subs, dual-band | 1.0× frame | 11 min65 subs | 12 min72 subs | 17 min104 subs |
| ZWO Seestar S3010 s subs, dual-band | 1.2× frame | 11 min67 subs | 12 min74 subs | 17 min104 subs |
| ZWO Seestar S30 Pro10 s subs, dual-band | 63% | 12 min70 subs | 13 min78 subs | 19 min112 subs |
| DwarfLab DWARF 315 s subs, dual-band | 86% | 12 min48 subs | 14 min55 subs | 21 min86 subs |
| DwarfLab DWARF mini15 s subs, dual-band | 1.2× frame | 9 min38 subs | 11 min43 subs | 16 min63 subs |
| DwarfLab Draco30 s subs, dual-band | 1.1× frame | 15 min30 subs | 15 min30 subs | 15 min30 subs |
| DwarfLab DWARF II15 s subs | 79% | 31 min126 subs | 42 min167 subs | 1 h 26 min346 subs |
| Vaonis Vespera II10 s subs | Only just | 8 min47 subs | 11 min69 subs | 28 min166 subs |
| Vaonis Vespera Pro10 s subs | 87% | 18 min111 subs | 26 min157 subs | 1 h361 subs |
| Vaonis Vespera 310 s subs | Only just | 7 min45 subs | 11 min66 subs | 26 min159 subs |
| Vaonis Vespera Pro 210 s subs | 86% | 17 min105 subs | 25 min150 subs | 57 min345 subs |
| Unistellar eQuinox 24 s subs | 2.5× frame | 9 min137 subs | 11 min172 subs | 21 min323 subs |
| Unistellar Odyssey4 s subs | 2.5× frame | 47 min701 subs | 55 min827 subs | 1 h 32 min1,377 subs |
| Celestron Origin10 s subs | 1.7× frame | 5 min30 subs | 5 min30 subs | 8 min46 subs |
| Celestron Origin Mark II10 s subs | 1.9× frame | 5 min30 subs | 5 min30 subs | 11 min64 subs |
Imaging the emission nebula
Emission nebulae glow in a few narrow lines, mostly hydrogen-alpha (deep red) and doubly ionised oxygen (teal). A dual-band filter passes those lines and blocks most skyglow, which is why it cuts the time needed from a suburban sky so dramatically. Use it. From a genuinely dark site the gain is smaller because there is less skyglow to block, and read noise becomes the limit, which is where longer subs (EQ mode, or Expert Mode on a Vespera) earn their keep.
Stars lose colour through a dual-band filter; a short broadband stack blended in fixes that if you care.
Per-telescope pages
- How long to image the Orion Nebula with the ZWO Seestar S50
- How long to image the Orion Nebula with the ZWO Seestar S50 Pro
- How long to image the Orion Nebula with the ZWO Seestar S30
- How long to image the Orion Nebula with the ZWO Seestar S30 Pro
- How long to image the Orion Nebula with the DwarfLab DWARF 3
- How long to image the Orion Nebula with the DwarfLab DWARF mini
- How long to image the Orion Nebula with the DwarfLab Draco
- How long to image the Orion Nebula with the DwarfLab DWARF II
- How long to image the Orion Nebula with the Vaonis Vespera II
- How long to image the Orion Nebula with the Vaonis Vespera Pro
- How long to image the Orion Nebula with the Vaonis Vespera 3
- How long to image the Orion Nebula with the Vaonis Vespera Pro 2
- How long to image the Orion Nebula with the Unistellar eQuinox 2
- How long to image the Orion Nebula with the Unistellar Odyssey
- How long to image the Orion Nebula with the Celestron Origin
- How long to image the Orion Nebula with the Celestron Origin Mark II