Assertion: planet's period | /r/HasProperty | brief
Facets:
value: compared to the much larger planets
type: OTHER
value: necessarily
type: DEGREE
Source sentences:
text: However, because of the relatively small size of the bodies, the period of melting was necessarily brief (compared to the much larger planets), and had generally ended about 4.5 billion years ago, in the first tens of millions of years of formation.