›› 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 mille [French]
light day to li [modern China]
light day to estadio [Portugal]
light day to pearl
light day to legua [Spanish, post-1568]
light day to petametre
light day to foot [Egypt]
light day to cuadra [Argentina]
light day to stadium
light day to fingerbreadth