Assertion: newtonian telescope's length | /r/HasProperty | actual distance
Facets:
value: to the focal point
type: LOCATION
value: from the lens
type: OTHER
value: from mirror
type: LOCATION
Source sentences:
text: In refractors and Newtonian telescopes (described more below), the focal length is the actual distance from the lens or mirror to the focal point, as shown below.