ocr: ASTRONOMICAL UNIT AU. A unit of length that equals the Earth's distance from the Sun (More precisely the semimajor axis, which is 149.6 million km or approximately eight light-minutes). AU is mainly used for distances within the Solar system. Some examples: The distance of Mars from the Sun is 1.52 AU. The closest planet to the Sun, Mercury has a distance of 0.387. AU and the fur- thest, Pluto almost exactly 100 times more, 39.56 AU. The distance to the Moon is 0.026 - AU (= 1.2 light seconds.) One light- year is 63,240 / AU. The distance to the Sun is one AUi. i.g. 150 million km. The second ...
