Assertion: moon's crater | /r/CreatedBy | impact
Facets:
value: usually
type: TEMPORAL
Source sentences:
text: Craters, usually caused by impacts, have been seen on every moon, asteroid, and comet nucleus ever imaged in detail -- until now.
text: Craters, usually caused by impacts, have been seen on every moon, asteroid, and comet nucleus ever imaged in detail -- until now.