Vela Supernova Remnant (SNR G263.9−03.3 / NGC 2736)
Coordinates, VLBI pulsar distance (287 pc), 11,000-year core-collapse shell, Pencil Nebula NGC 2736, and observing guide for the Vela SNR.
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 mag | ± 0.5 mag | Wide-field integrated optical filament emission (NGC 2736 is V≈12.0) | model-dependent | Revised New General Catalogue and Index Catalogue (RNGC/IC) |
| Heliocentric distance (VLBI Vela Pulsar) | 936 ly | ± 60 ly | VLBI trigonometric parallax of PSR B0833-45 (287 ± 19 pc, Dodson et al. 2003) (J2000.0) | definitive | SIMBAD Astronomical Database (CDS) |
| Full blast-wave angular diameter | 480 arcmin | ± 30 arcmin | ROSAT/eROSITA X-ray and optical filament shell (~8.0° diameter) | definitive | Revised New General Catalogue and Index Catalogue (RNGC/IC) |
J2000 Equatorial Sky Chart & Culmination Altitude
The chart below plots Vela Supernova Remnant (Gum 16 & Pulsar) at RA 08h 35m 20.61s, Dec -45° 10′ 35.0″ within Vela, 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 Vela Supernova Remnant (Gum 16, SNR G263.9−03.3) is one of the closest and largest supernova remnants in the sky, spanning a colossal 8 degrees across southern Vela (16 full Moons wide, or ~130 light-years physically) at a VLBI parallax distance of just 936 light-years (287 ± 19 parsecs). Formed roughly 11,000 years ago when a massive star exploded inside the already-existing Gum Nebula superbubble, the cataclysm would have blazed in prehistoric skies at roughly visual magnitude −10 to −11—bright as a quarter Moon and easily visible in midday sunlight.
Near the center of the lacy web of optical and X-ray filaments sits the Vela Pulsar (PSR B0833−45 / HU Velorum), a young neutron star spinning 11.195 times per second (period 89.33 milliseconds) whose discovery by University of Sydney astronomers in 1968 provided the first direct observational link between a supernova remnant and a pulsar. Chandra X-ray movies of the Vela Pulsar reveal a tilted double-ring torus and a precessing relativistic polar jet shooting outward at 70% of the speed of light, while radio timing frequently catches sudden rotational 'glitches' caused by superfluid vortex unpinning inside the neutron star's crust.
Superposed on the southeastern corner of the Vela remnant lies the younger (~700–1,200 year old) 'Vela Junior' supernova remnant (RX J0852.0−4622), while on the eastern edge sits the brightest optical shock filament of the complex: NGC 2736, the Pencil Nebula, discovered by Sir John Herschel in 1835.
Practical Visual Observing Guide
- Centered near declination −45° in western Vela (visible south of ~35°N); the brightest visual segment is the Pencil Nebula (NGC 2736, RA 09h 00.4m, Dec −45°57′), located 5° south-southwest of Lambda Velorum (Suhail).
- Because the full Vela shell covers 8 degrees, visual observers target individual high-surface-brightness [O III] shock filaments—above all the 20′ × 2′ linear streak of the Pencil Nebula (NGC 2736).
- In a 130–250 mm telescope at 40×–80× equipped with an O-III filter under dark skies, NGC 2736 looks like a ghostly ruler-straight laser beam or broom handle with a sharp eastern shock edge.
Catalog Cross-Identifications & Aliases
Common Aliases: Vela Supernova Remnant · Vela SNR · Gum 16 · NGC 2736 · Pencil Nebula
| Catalog Authority | Identifier |
|---|---|
| NGC | NGC 2736 |
| SIMBAD | Vela SNR |
| WIKIDATA | Q14052 |
Related Objects, Comparisons & Guides
Puppis A (Cosmic Cannonball Supernova Remnant)
Coordinates, kinematic H I distance (1.3 kpc / 4,240 ly), hypervelocity neutron star RX J0822-4300, and data for Puppis A in Puppis.
Veil Nebula (Cygnus Loop NGC 6960/6992)
Coordinates, Gaia distance (735 pc), O-III filament structure, and visual filter guide for the Veil Nebula supernova remnant in Cygnus.
Crab Nebula (Messier 1 Supernova Remnant)
Coordinates, Gaia DR3 distance (1.96 kpc), SN 1054 history, pulsar wind physics, and observing guide for the Crab Nebula (M1) in Taurus.
Trigonometric Parallax, Parsecs & Gaia DR3
How trigonometric parallax (d_pc = 1 / p_arcsec), the distance modulus equation, Hipparcos, and Gaia DR3 microarcsecond astrometry measure cosmic distances.
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.
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
- 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
- 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