1. the elapsed time it takes for light (or radio signals) to travel between the Earth and a celestial object; [syn: one-way light time, OWLT]
WordNet (r) 3.0 (2006):
one-way light time
n 1: the elapsed time it takes for light (or radio signals) to
travel between the Earth and a celestial object [syn: one-
way light time, OWLT]