|MadSci Network: Astronomy|
The distance to the Moon could be determined from a measurement of parallax. If the Moon is observed by two people separated by about 420 miles, the position of the Moon, with respect to the fixed stars, will vary by about one-tenth of a degree. Although this sounds small, it can be discerned by the naked eye and measured quite precisely with the use of telescopes. If the two data mentioned above were the the actual measurements, then the distance to the moon would be given by: D = (420 miles)/sin(0.1 degree) = 240,642 miles.
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