How
Long is a Light-Year?
The light-year
is a measure of distance, not time. It is the total distance that a beam
of light, moving in a straight line, travels in one year. To obtain an
idea of the size of a light-year, take the circumference of the earth
(24,900 miles), lay it out in a straight line, multiply the length of
the line by 7.5 (the corresponding distance is one light-second), then
place 31.6 million similar lines end to end. The resulting distance is
almost 6 trillion (6,000,000,000,000) miles!
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