HR 1903

E545061

HR 1903 is the Bright Star Catalogue designation for Alnilam, the luminous blue supergiant star forming the central point of Orion’s Belt.

All labels observed (1)

Label Occurrences
HR 1903 canonical 2

How this entity was disambiguated

Statements (46)

Predicate Object
instanceOf Bright Star Catalogue object ⓘ
blue supergiant ⓘ
star ⓘ
alsoKnownAs Alnilam ⓘ
Epsilon Orionis ⓘ
apparentMagnitudeV 1.69 ⓘ
belongsTo Milky Way Galaxy ⓘ
linked to: Milky Way

Orion OB1 association ⓘ
bestViewingSeason northern winter ⓘ
catalogDesignation BD−01°969 ⓘ
HD 37128 ⓘ
HIP 26311 ⓘ
HR 1903 ⓘ
SAO 132444 ⓘ
colorIndex blue ⓘ
constellation Orion ⓘ
declination −01° 12′ ⓘ
distanceFromEarth_ly about 2000 ⓘ
distanceFromEarth_pc about 600 ⓘ
dominantEnergyOutput ultraviolet radiation ⓘ
effectiveTemperature_K about 27500 ⓘ
equatorialCoordinateSystem J2000 ⓘ
evolutionaryStage supergiant ⓘ
galacticPopulation Population I ⓘ
hasProperName Alnilam ⓘ
hasRadialVelocity about +27 km/s ⓘ
hasRotationalVelocity about 40 km/s ⓘ
hemisphereVisibility both northern and southern hemispheres ⓘ
influences surrounding interstellar medium in Orion ⓘ
isMassiveStar true ⓘ
isOneOf three main stars of Orion’s Belt ⓘ
isPartOf Orion’s Belt ⓘ
linked to: Orion Belt region
isSingleStar likely ⓘ
isVisibleToNakedEye true ⓘ
luminosityComparedToSun about 375000 ⓘ
massComparedToSun about 30 ⓘ
metallicityComparedToSun slightly subsolar ⓘ
nameEtymology from Arabic meaning “string of pearls” or “sapphire” ⓘ
neighboringBeltStar Alnitak ⓘ
Mintaka ⓘ
positionInAsterism central star of Orion’s Belt ⓘ
radiusComparedToSun about 32 ⓘ
rightAscension 05h 36m ⓘ
spectralType B0Ia ⓘ
variableStarType Alpha Cygni-type candidate ⓘ
willEndAs core-collapse supernova ⓘ

How these facts were elicited

Referenced by (2)

Full triples — surface form annotated when it differs from this entity's canonical label.

Alnilam → catalogIdentifier → HR 1903 ⓘ
HR 1903 → catalogDesignation → HR 1903 ⓘ