›› 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 lug [great]
light-year to league [nautical]
light-year to exametre
light-year to elle [Vienna]
light-year to legua
light-year to palm [US, Roman major]
light-year to Scots foot
light-year to kyu
light-year to perch
light-year to metre