Flame Nebula (NGC 2024 / Sh2-277)
Coordinates, Gaia DR3 distance (415 pc), IRS 2b O8 V hidden ionizer, maple-leaf dust lanes, and observing guide for NGC 2024 in Orion.
Provenance-Backed Scientific Measurements
Every measurement below preserves its unit, uncertainty interval, observational method, reference epoch, quality status, and primary catalog source. See Uncertainty & Provenance for how competing measurements are handled.
| Parameter | Value | Uncertainty | Method & Epoch | Quality Status | Source Archive |
|---|---|---|---|---|---|
| Integrated visual magnitude (V) | 7.2 mag | ± 0.3 mag | Integrated optical emission photometry | high-confidence | Revised New General Catalogue and Index Catalogue (RNGC/IC) |
| Heliocentric distance | 1350 ly | ± 35 ly | Gaia DR3 astrometric parallax of Orion B periphery stars (415 ± 10 pc) (J2016.0) | definitive | ESA Gaia Archive — Data Release 3 |
| Apparent diameter | 30 arcmin | ± 2 arcmin | Optical H-alpha emission shell (30′ × 30′) | high-confidence | Revised New General Catalogue and Index Catalogue (RNGC/IC) |
| Embedded protostellar cluster age | 0.0004 Gyr | ± 0.0002 Gyr | Chandra X-ray & JWST infrared YSO disk fraction (0.4 ± 0.2 Myr) | model-dependent | SIMBAD Astronomical Database (CDS) |
J2000 Equatorial Sky Chart & Culmination Altitude
The chart below plots Flame Nebula (NGC 2024 near Alnitak) at RA 05h 41m 42.00s, Dec -01° 51′ 00.0″ within Orion, alongside peak meridian transit altitudes for 40°N and 30°S observers. Use the RA/Dec Coordinate Converter to compute exact culmination altitude for your latitude.
Astrophysical Context & Structure
The Flame Nebula (NGC 2024, Sharpless 2-277—often called the 'Maple Leaf' or 'Tank Tracks' Nebula by visual observers) is a bright, 30-arcminute H II emission region located 1,350 light-years (415 ± 10 parsecs) away in the Orion B molecular cloud, perched just 15 arcminutes northeast of the dazzling 1.77-magnitude eastern Belt star Alnitak (ζ Orionis). Discovered by William Herschel on January 1, 1786, the nebula's fiery orange-red emission shell is sliced down the middle by a jagged, branching silhouette of opaque foreground molecular dust.
Although Alnitak sits right next to NGC 2024 on the sky, the blue supergiant is actually a foreground star lying several hundred light-years closer to Earth and does NOT ionize the Flame Nebula. In 2003, near-infrared K-band spectroscopy penetrated 24 magnitudes of visual dust absorption inside the dark central lane to identify the true powerhouse: IRS 2b, a hot young O8 V–B0 V star (~20 solar masses) embedded at the heart of a dense ~400,000-year-old cluster of over 800 young stellar objects.
Recent ALMA millimeter and JWST observations of NGC 2024 have revealed two distinct chronological populations of protoplanetary disks on either side of the central ionization front, as well as free-floating brown dwarfs and planetary-mass objects.
Practical Visual Observing Guide
- Situated immediately (15′) east-northeast of 1.77-magnitude Alnitak (ζ Orionis), the easternmost star of Orion's Belt, and 30′ north of the Horsehead Nebula (Barnard 33).
- The single biggest visual challenge is the blinding glare of Alnitak: position your telescope so Alnitak sits just outside the western edge of the eyepiece field of view (or use an occulting bar).
- With Alnitak nudged out of the field under dark skies (Bortle 1–4), even a 10×50 binocular or an 80–150 mm telescope at 40×–80× clearly reveals the two bright emission halves split by the dark central trunk and branching 'maple leaf' veins.
Catalog Cross-Identifications & Aliases
Common Aliases: NGC 2024 · Flame Nebula · Tank Tracks Nebula · Sharpless 2-277
| Catalog Authority | Identifier |
|---|---|
| NGC | NGC 2024 |
| SIMBAD | NGC 2024 |
| WIKIDATA | Q488513 |
Related Objects, Comparisons & Guides
Horsehead Nebula (Barnard 33 / IC 434)
Coordinates, Gaia DR3 distance (415 pc), Sigma Orionis ionization wall IC 434, and H-beta filter observing guide for the Horsehead Nebula in Orion.
Messier 78 (NGC 2068 Reflection Nebula)
Coordinates, Gaia DR3 distance (410 pc), magnitude 8.3, McNeil's Nebula variable outburst, and observing guide for M78 in Orion.
Orion Nebula (Messier 42 / NGC 1976)
Coordinates, VLBI/Gaia distance (412 pc), Trapezium ionizing cluster, and visual observing guide for the Orion Nebula (M42) in Orion.
Surface Brightness & Extended Objects Guide
Why surface brightness (mag/arcsec²) governs nebula and galaxy visibility more than integrated magnitude, and how exit pupil controls eyepiece contrast.
Bortle Dark-Sky Scale & Sky Brightness Guide
Reference guide to the 9-class Bortle Dark-Sky Scale, zenith Sky Quality Meter (SQM) readings in mag/arcsec², naked-eye limiting magnitude, and light pollution.
Scientific Sources & Dataset Provenance
- Revised New General Catalogue and Index Catalogue (RNGC/IC) (2024/2026 edition): Steinicke, W. 2010, Observing and Cataloguing Nebulae and Star Clusters (Cambridge Univ. Press); Verga, M. OpenNGC (CC-BY-SA 4.0 / data tables) — Wolfgang Steinicke / OpenNGC
- ESA Gaia Archive — Data Release 3 (DR3 (2022-06-13)): Gaia Collaboration, Vallenari, A., et al. 2023, A&A, 674, A1 (Gaia Data Release 3) — European Space Agency / Gaia DPAC
- SIMBAD Astronomical Database (CDS) (2026-10 release): Wenger, M., et al. 2000, A&AS, 143, 9 (The SIMBAD astronomical database) — Centre de Données astronomiques de Strasbourg