Assertion: newtonian telescope's mirror | /r/HasProperty | housed in an aluminum cell
Facets:
Source sentences:
text: A center-spotted parabolic primary mirror housed in an aluminum cell fitted with six "push/pull" collimation knobs that is guaranteed to be diffraction limited makes easy, no-tool collimation possible.
text: The center-spotted parabolic primary mirror is guaranteed to be diffraction-limited, and is housed in an aluminum cell that is fitted with six "push/pull" collimation knobs for easy collimation without tools.