Coelostat

Solar telescopes are special purpose telescopes used to observe the sun. While, like all telescopes, they need a large diameter mirror to achieve the best possible diffraction limit, they do not need the associated light-collecting power. Rather, the heat generated by the tightly-focused sunlight poses a major design problem.
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Noun
1. optical device used to follow the path of a celestial body and reflect its light into a telescope; has a movable and a fixed mirror
(hypernym) optical device

Adjustable mounted flat mirrors that continually reflect light from a star (if the sun it is a heliostat) into the aperature of unmanoeuverable heavy optical analysing equipment.

Eng: coelostat
Urdu: سماقرار۔ مقوم السما۔