Noun
a unit of distance equal to the distance that light travels in one year
light years
Another way to gather information would be to transport a vessel to and from the planet. The technology exists to do this, but at 20 light years from the Earth, it would take 200 years for astronomers to receive the result.
Another way to gather information would be to transport a vessel to and from the planet. The technology exists to do this, but at 20 light years from the Earth, it would take 200 years for astronomers to receive the result.