›› 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 1.05700083402E-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 lieue [France]
light year to elle [Germany]
light year to point [Britain, US]
light year to block [East U.S.]
light year to ridge
light year to cable [British]
light year to mile [statute, US]
light year to pe [Portuguese]
light year to furlong [international]
light year to point [Didot]