›› Measurement unit: light-year

Full name: light year

Plural form: light years

Symbol: ly

Alternate spelling: lightyear

Category type: length

Scale factor: 9460730472580800


›› SI unit: metre

The SI base unit for length is the metre.
1 metre is equal to 1.0570008340246E-16 light-year.


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›› Definition: Light-year

A light year, abbreviated ly, is the distance light travels in one year: roughly 9.46 × 1012 kilometres (9.46 petametres, or about 5.88 × 1012 (nearly six trillion) miles). More specifically, a light year is defined as the distance that a photon would travel, in free space and infinitely far away from any gravitational or magnetic fields, in one Julian year (365.25 days of 86400 seconds each).


›› Sample conversions: light-year

light-year to meile [Austria]
light-year to milla [Spanish]
light-year to millimetre
light-year to palmo [Spanish]
light-year to sadzhen
light-year to pie [Italian]
light-year to pik
light-year to palm [Dutch]
light-year to cape rood
light-year to gigametre