VY Canis Majoris (HD 58061)
Coordinates, VLBA maser parallax distance (1.17 kpc), 1,420 R☉ hypergiant radius, asymmetric mass-loss arcs, and guide for VY Canis Majoris.
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 |
|---|---|---|---|---|---|
| Visual magnitude range (V) | 7.95 mag | ± 0.9 mag | AAVSO V-band monitoring (varies from 6.5 to 9.6 due to pulsation and dust ejections) | definitive | SIMBAD Astronomical Database (CDS) |
| VLBA water & SiO maser trigonometric distance | 1170 pc | ± 80 pc | VLBA radio-maser trigonometric parallax (Zhang et al. 2012: 0.83 ± 0.08 mas / 3,820 ± 260 ly) | definitive | SIMBAD Astronomical Database (CDS) |
| Photospheric radius | 1420 R☉ | ± 120 R☉ | VLTI/AMBER near-IR interferometric angular diameter (11.3 ± 0.3 mas; Wittkowski et al. 2012) | high-confidence | SIMBAD Astronomical Database (CDS) |
| Bolometric luminosity | 270000 L☉ | ± 40000 L☉ | Full optical-to-submillimeter dust SED integration at 1.17 kpc | high-confidence | SIMBAD Astronomical Database (CDS) |
| Effective temperature | 3490 K | ± 90 K | VLTI angular diameter + bolometric flux | high-confidence | SIMBAD Astronomical Database (CDS) |
J2000 Equatorial Sky Chart & Culmination Altitude
The chart below plots VY Canis Majoris (Extreme Red Hypergiant) at RA 07h 22m 58.33s, Dec -25° 46′ 03.2″ within Canis Major, 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
VY Canis Majoris (HD 58061), located 1.17 ± 0.08 kiloparsecs (3,820 light-years) away on the eastern edge of the giant molecular cloud surrounding the cluster NGC 2362 in Canis Major, is one of the largest, most luminous, and most extreme oxygen-rich red hypergiants known in the Milky Way. Combining its VLTI/AMBER near-infrared interferometric angular diameter (11.3 ± 0.3 milliarcseconds) with its VLBA radio-maser parallax yields a photospheric radius of 1,420 ± 120 solar radii (~6.6 AU)—if placed at the center of our Solar System, its surface would extend well past the orbit of Jupiter and two-thirds of the way to Saturn!
Born only ~8 million years ago as a ~25-to-32 solar-mass O9 main-sequence star, VY Canis Majoris now radiates 270,000 ± 40,000 solar luminosities while undergoing violent, episodic mass loss at a rate of ~6 × 10^-4 solar masses per year (shedding an entire Earth mass of gas and dust every 5 days!).
Hubble Space Telescope polarization imaging and ALMA submillimeter spectroscopy of VY Canis Majoris's 10-arcsecond circumstellar nebula reveal dozens of discrete, asymmetric arcs, knots, and loops ejected in random directions over the past 1,000 years—driven by giant convective super-granules and localized magnetic reconnection events similar to, but a hundred times more massive than, Betelgeuse's 2019–2020 Great Dimming.
Practical Visual Observing Guide
- Very easy to locate in Canis Major: find 1.83-magnitude Wezen (δ CMa), move 1.7° east to the compact 4.4-magnitude Tau Canis Majoris Cluster (NGC 2362), and look just 0.5° south of NGC 2362.
- In a 100–200 mm telescope at 80×–150×, VY Canis Majoris shines at magnitude ~7.9–8.5 with a striking, saturated blood-orange or crimson hue, and at 250×+ in large apertures looks slightly fuzzy due to its 2-arcsecond dust reflection halo.
Catalog Cross-Identifications & Aliases
Common Aliases: VY CMa · HD 58061 · HIP 35793
| Catalog Authority | Identifier |
|---|---|
| HIP | HIP 35793 |
| HD | HD 58061 |
| SIMBAD | V* VY CMa |
| WIKIDATA | Q183309 |
Related Objects, Comparisons & Guides
Wezen (Delta Canis Majoris Yellow Supergiant)
Coordinates, distance (~1,600 ly), magnitude 1.83, 215 R☉ yellow-white supergiant radius, and observing guide for Wezen in Canis Major.
UY Scuti (Pulsating Red Supergiant in Scutum)
Coordinates, revised Gaia DR3 distance (~1.55 kpc vs older 2.9 kpc), ~755–909 R☉ radius revision, 740-day pulsation, and guide for UY Scuti.
Betelgeuse (Alpha Orionis Red Supergiant)
Coordinates, competing optical vs radio distances (168 vs 222 pc), radius, Great Dimming physics, and observing guide for Betelgeuse.
Angular Size, Separation & Field of View
How angular diameter (degrees, arcminutes, arcseconds), spherical angular separation, and small-angle physical diameter relate to telescope field of view.
Measurement Uncertainty & Optics in Astronomy
How random vs systematic errors, asymmetric error bars, model dependencies, and optical aperture/exit-pupil limits shape astronomical measurements.
Scientific Sources & Dataset Provenance
- 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
- Hipparcos New Reduction Catalog (2007 New Reduction): van Leeuwen, F. 2007, A&A, 474, 653 (Validation of the new Hipparcos reduction) — ESA / van Leeuwen (2007)