Assertion: telescope | /r/CapableOf | compensate for the rotation of the earth
Facets:
value: to keep an object
type: PURPOSE
Source sentences:
text: Un-driven altazimuth mounted telescopes need to be "nudged" every few minutes along both axes to compensate for the rotation of the Earth to keep an object in view (as opposed to one axis for un-driven equatorial mounts), an exercise that becomes more difficult with higher magnifications.