the branch of astronomy that uses radar to map the surfaces of planetary bodies, as the moon and Venus, and to determine periods of rotation.
Origin of radar astronomy
First recorded in 1955–60
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
the use of radar to map the surfaces of the planets, their satellites, and other bodies
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
The scientific study of nearby astronomical objects by reflecting microwaves off the objects and analyzing the echoes. The techniques of radio astronomy can be tailored to answer specific questions, such as the rotation period of the inner planets and the Moon. They have has also been used to test General Relativity, measure distances and features of planets in the solar system, and determine the composition, position, and spin of asteroids.
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