HD 39801
E557730
Milky Way star
bright giant star
cool supergiant
evolved massive star
red supergiant star
semiregular variable star
HD 39801 is the bright red supergiant star Betelgeuse, one of the most prominent stars in the constellation Orion and among the largest visible to the naked eye.
Statements (50)
| Predicate | Object |
|---|---|
| instanceOf |
Milky Way star
ⓘ
bright giant star ⓘ cool supergiant ⓘ evolved massive star ⓘ red supergiant star ⓘ semiregular variable star ⓘ |
| absoluteMagnitudeV | about −5.5 ⓘ |
| age_millionYears | about 8 to 10 ⓘ |
| alsoKnownAs |
Alpha Orionis
NERFINISHED
ⓘ
Betelgeuse NERFINISHED ⓘ |
| angularDiameter_mas | about 40 to 50 milliarcseconds ⓘ |
| apparentMagnitudeV | about 0.0 to +1.6 ⓘ |
| averageApparentMagnitudeV | about +0.5 ⓘ |
| bayerDesignation | α Orionis NERFINISHED ⓘ |
| catalogNumber |
BD+07 1055
NERFINISHED
ⓘ
HD 39801 ⓘ HIP 27989 NERFINISHED ⓘ HR 2061 NERFINISHED ⓘ |
| colorIndexBMinusV | +1.85 ⓘ |
| constellation | Orion NERFINISHED ⓘ |
| declination_J2000 | +07° 24′ 25″ ⓘ |
| dimmingCause2019_2020 | combination of dust formation and surface changes ⓘ |
| distanceFromEarth_ly | about 550 to 650 light-years ⓘ |
| distanceFromEarth_pc | about 170 to 200 parsecs ⓘ |
| effectiveTemperature_K | about 3500 ⓘ |
| evolutionaryStage | late-stage red supergiant ⓘ |
| futureEvolution | core-collapse supernova progenitor ⓘ |
| galacticPopulation | thin disk ⓘ |
| hasCircumstellarMaterial | yes ⓘ |
| hasDustShell | yes ⓘ |
| hasMassLoss | yes ⓘ |
| hemisphereVisibility | both hemispheres ⓘ |
| hostGalaxy | Milky Way NERFINISHED ⓘ |
| isOneOfBrightestStars | yes ⓘ |
| locatedIn | Orion OB1 association NERFINISHED ⓘ |
| luminosity_solar | about 100000 ⓘ |
| mass_solar | about 15 to 20 ⓘ |
| massLossRate_solarMassPerYear | of order 10^-6 to 10^-5 ⓘ |
| metallicity_FeH | near solar ⓘ |
| notableEvent | experienced major dimming in 2019–2020 ⓘ |
| parallax_mas | about 5 to 6 milliarcseconds ⓘ |
| properMotionDec_masPerYear | about 10 ⓘ |
| properMotionRA_masPerYear | about 24 ⓘ |
| radialVelocity_kmPerSec | about +20 ⓘ |
| radius_solar | about 700 to 900 ⓘ |
| rankByBrightness | among top 10 brightest night-sky stars ⓘ |
| rightAscension_J2000 | 05h 55m 10.3s ⓘ |
| spectralType | M1–M2 Ia–ab ⓘ |
| variableType | semiregular (SRC) ⓘ |
| visibleToNakedEye | yes ⓘ |
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.