Assertion: nebula's star | /r/CapableOf | vary to boot
Facets:
value: over periods of only 30 minutes
type: TEMPORAL
value: significantly
type: DEGREE
Source sentences:
text: While variable stars are not exactly uncommon, it is highly unusual for central stars in planetary nebulae to be variable, and to vary significantly over periods of only 30 minutes or so, to boot.