radial velocity(redirected from radial velocities)
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The velocity, or a component of the velocity, of an object as it moves toward or away from an observer, as a star or galaxy observed from Earth. Periodic changes in the radial velocities of stars may indicate the presence of orbiting planets even if the planets themselves are not directly observable.
(General Physics) the component of the velocity of an object, esp a celestial body, directed along a line from the observer to the object