radial motion

[ rey-dee-uhl moh-shuhn ]

noun

, Astronomy.

1. the component of the motion of a star away from or toward the earth along its line of sight, expressed in miles or kilometers per second and determined by the shift in the wavelength of light emitted by the star.

Word History and Origins

Origin of radial motion¹

First recorded in 1880–85

Example Sentences

The orbit of this star has been exhaustively investigated by Wright from Campbells observations of the radial motion.

From Project Gutenberg

Keeler's were the first trustworthy determinations of radial motion obtained visually.

From Project Gutenberg