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Note: Distance is from center to center of orbiting bodies.
Kilometers divided by 1.6093 = miles.
Many sources, such as beginning astronomy textbooks, yearbooks, and atlases, give the distance to the moon as 384,400 kilometers (km), and 0.055 as the flattening or eccentricity of the moon's elliptical orbit around the Earth.
The moon travels around Earth in an elliptical orbit, with the Earth at one of the two focuses (foci) of the ellipse. As a result the distance to the moon varies by quite large amounts. Its close (or perigee) distance is 384,400 x (1- 0.055) = 363,258 km. Its far (or apogee) distance is 384,400 x (1+0.055) = 405,542 km. BUT these values turn out to be the mean or average values. See the table below for actual distances.
The actual (computed) distances over 10 centuries, from 1500 to 2500, have been calculated by the Belgian astronomer, Jean Meeus, to be as small as 356,371 km or as large as 406,720 km./1 These values differ from the MEAN values by 6,887 km and 1,178 km respectively
An excellent and easy-to-use source for the moon's position and distance is "Multiyear Interactive Computer Almanac" produced by the US Naval Observatory, Wash. DC and published by Willman-Bell, Inc., PO box 35025, Richmond, VA 232235. The program called "MICA15" is on one CDRom for both IBM and MAC systems. Included with the disk is an information and instruction book.
I used MICA15 to scan moon distances for the one year, 2000, shown in TABLE 1. The same source was used for the ten-year period, 1995 to 2005. For this ten years, the smallest distance (356,613.970 km) between Earth and Moon for this period occurred on November 4, 1998. The largest occurred on March 14, 2002 when the moon was 406,706.975 km away.
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