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Light-year

A light-year, alternatively spelled light year (ly or lyr), is a unit of length used to express astronomical distances and is equal to exactly 9460730472580.8 km, which is approximately 9.46 trillion kilometres or 5.88 trillion miles. As defined by the International Astronomical Union (IAU), a light-year is the distance that light travels in vacuum in…

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astronomical units
63241 au · 0.3066 pc
imperial and US units
5.8786×1012 mi
metric (SI) units
9.4607×1015 m · 9.46073 Pm
Symbol
ly
Unit of
length
Unit system
astronomy units

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Light-year

Nodes49
Edges48
Triples63
Avg. degree1.96
Density0.040816
Components1

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Light-year

Top relations

related to Definitions · 19
Light-year → As, Astronomical Constants, Both, French, From, German, Gregorian, IAU, International, International Astronomical Union, ISO, Italian, Julian, Lichtjahr, Lj, Spanish, System, The, Tropical
related to history · 14
Light-year → Bessel, Cygni, Cygni's, Earth's, Fizeau, Foucault, Fraunhofer, Friedrich Bessel, He, In, It, Joseph, Sun, The
related to Related units · 7
Light-year → Distances, For, However, Light, The, The Hayden Planetarium, Units
is a · 3
Light-year → distance that light travels in vacuum in one Julian year, odd name, product of the Julian year
related to External links · 3
Light-year → The, Wiktionary, Wiktionary-logo-en-v2
related to Usage of term · 3
Light-year → Distances, Galaxies, Sloan Great Wall
astronomical units · 2
Light-year → 0.3066 pc, 63241 au
metric (SI) units · 2
Light-year → 9.46073 Pm, 9.4607×1015 m
imperial and US units · 1
Light-year → 5.8786×1012 mi
Symbol · 1
Light-year → ly

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Important terminology

light used unit astronomical year distances light-years units distance speed iau time defined popular star system ly length stars one

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
Light-yearastronomical units63241 au1.00infobox
Light-yearastronomical units0.3066 pc1.00infobox
Light-yearimperial and US units5.8786×1012 mi1.00infobox
Light-yearmetric (SI) units9.4607×1015 m1.00infobox
Light-yearmetric (SI) units9.46073 Pm1.00infobox
Light-yearSymbolly1.00infobox
Light-yearUnit oflength1.00infobox
Light-yearUnit systemastronomy units1.00infobox
Light-yearis adistance that light travels in vacuum in one Julian year0.90text
Light-yearis aproduct of the Julian year0.90text
Light-yearis aodd name0.90text
quasarsinstance ofDistances to objects0.80text

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