Assertion: motion's motion | /r/HasProperty | quarter
Facets:
Source sentences:
text: But it is moving through space relative to nearby stars and interstellar gas at about 80 miles per second (most such motions are only a quarter that speed), and as the star and the gas leaving it plow through the interstellar medium a "bow shock" is formed, like the bow wave in front of a speedboat, and a long "wake" or "tail" has formed behind the star.