›› Measurement unit: light-day

Full name: light day

Plural form: light days

Alternate spelling: lightday

Category type: length

Scale factor: 25902068371200


›› SI unit: metre

The SI base unit for length is the metre.
1 metre is equal to 3.8606955462749E-14 light-day.


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›› Definition: Light-day

A light day (also written light-day) is a unit of length. It is defined as the distance light travels in an absolute vacuum in one day (of 86,400 seconds) or 25,902,068,371,200 metres (~26 Tm).

Note that this value is exact, since the metre is actually defined in terms of the speed of light. The light day isn't very frequently used at all since there are few astronomical objects or distances of that magnitude; the Oort cloud, for example, is thought to extend between 290 and 580 light-days out from the Sun.


›› Sample conversions: light-day

light-day to light second
light-day to stride [Roman]
light-day to braccio [Italy]
light-day to pertica
light-day to li [imperial China]
light-day to petametre
light-day to decametre
light-day to ligne [Swiss]
light-day to legua
light-day to milha [Portuguese]