Assertion: comet's period | /r/HasProperty | 200 years
Facets:
Source sentences:
text: Comet Shoemaker–Levy 9 was the ninth periodic comet (a comet whose orbital period is 200 years or less) discovered by the Shoemakers and Levy, hence its name.
text: It fits the classical definition of a Halley-type comet with (20 years < period < 200 years).