Assertion: telescope | /r/CapableOf | use curved mirrors
Facets:
value: in place of the objective lens
type: MANNER
value: to gather light
type: PURPOSE
Source sentences:
text: However, most telescopes today use curved mirrors to gather light from the night sky.
text: For reflecting telescopes, which use a curved mirror in place of the objective lens, theory preceded practice.
text: Scientists of the time knew of no way to avoid this problem with lenses, so they designed telescopes using curved mirrors instead.