light-hour


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light-hour

[′līt‚au̇·ər]
(astronomy)
The distance traveled by light in 1 hour in a vacuum.
References in periodicals archive ?
At its closest approach last March, S2 swung within just 17 light-hours (125 astronomical units) of the black hole, only three times the average distance of Pluto from the Sun.
from the home star (more than 10 light-hours away) and 44 a.
Comparing these numbers to Pluto's average distance (5 light-hours from the Sun) helps us to picture how much "empty" space lies between the stars.