Assertion: planet | /r/CapableOf | trade gravitational potential energy
Facets:
value: for kinetic energy
type: PURPOSE
Source sentences:
text: As a planet approaches periastron, its speed increases as it trades gravitational potential energy for kinetic energy, just as a falling object on Earth accelerates as it falls; as the planet reaches apastron, its speed decreases, just as an object thrown upwards on Earth slows down as it reaches the apex of its trajectory.