Flame Nebula

NGC 2024 · Emission nebula in Orion

Magnitude
7.2
Size
30′
Effective surface brightness
21.8 mag/arcsec²
Best months
Nov, Dec, Jan
Declination
-2°
Filter
Dual-band recommended

A bright emission nebula beside Alnitak, split by a dark lane like a tree. Alnitak's glare is the main problem; keep it out of the frame if you can.

Reachable from mid-northern latitudes (UK, northern US, central Europe) and from the south.

How long with each smart telescope

Total integration for a solid image of the Flame Nebula, default sub length, recommended filter. Click a cell for the full Bortle 1 to 9 table.
TelescopeBortle 3 (rural)Bortle 5 (suburban)Bortle 7 (urban edge)
ZWO Seestar S5010 s subs, dual-band36 min219 subs40 min240 subs55 min329 subs
ZWO Seestar S50 Pro10 s subs, dual-band26 min157 subs30 min179 subs46 min276 subs
ZWO Seestar S3010 s subs, dual-band23 min139 subs26 min159 subs41 min249 subs
ZWO Seestar S30 Pro10 s subs, dual-band28 min170 subs32 min193 subs49 min295 subs
DwarfLab Dwarf 315 s subs, dual-band38 min152 subs43 min173 subs1 h 06 min266 subs
DwarfLab Dwarf Mini15 s subs, dual-band20 min79 subs23 min92 subs38 min152 subs
DwarfLab Dwarf II15 s subs1 h 23 min332 subs1 h 54 min456 subs4 h 09 min998 subs
Vaonis Vespera II10 s subs19 min116 subs30 min183 subs1 h 19 min476 subs
Vaonis Vespera Pro10 s subs55 min331 subs1 h 19 min472 subs3 h 01 min1,087 subs
Unistellar eQuinox 24 s subs25 min375 subs32 min479 subs1 h 02 min936 subs
Unistellar Odyssey4 s subs2 h 12 min1,976 subs2 h 37 min2,356 subs4 h 28 min4,016 subs
Celestron Origin10 s subs5 min30 subs8 min47 subs22 min130 subs

Open in the calculator

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) 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