parallactic motion

American  

noun

Astronomy.

1. the apparent motion of stars due to the earth's orbital motion.

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Etymology

Origin of parallactic motion

First recorded in 1885–90

Example Sentences

If we ascertain the parallactic motion of a group of stars, then we can find their average distance.

From Project Gutenberg

By parallactic motion is meant the apparent displacement in consequence of the solar motion which is now known with great accuracy, and amounts to 19.5 kilometers per second.

From Project Gutenberg

In both cases the motion may be either a reflex of the motion of the observer, and is then called parallactic motion, or it may be caused by a real motion of the star.

From Project Gutenberg

From the parallactic motion of the star it is possible to deduce its distance from the sun, or its parallax.

From Project Gutenberg