siderostat

American  

[sid-er-uh-stat] / ˈsɪd ər əˌstæt /

noun

1. a telescopic device for reflecting the light of a star in a constant direction, the chief component of which is a plane mirror turned by a clock mechanism to correct for the rotation of the earth.

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siderostat British  

/ ˈsaɪdərəʊˌstæt /

noun

1. an astronomical instrument consisting essentially of a plane mirror driven about two axes so that light from a celestial body, esp the sun, is reflected along a constant direction for a long period of time See also heliostat Compare coelostat

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Other Word Forms

• siderostatic
  adjective

Etymology

Origin of siderostat

First recorded in 1875–80; sidero- ² + -stat

Example Sentences

Palais de l'Optique, Paris 49·2 197 Gautier, 1900 Mounted as a siderostat in connection with a plane mirror 79 inches across.

From A Popular History of Astronomy During the Nineteenth Century Fourth Edition by Clerke, Agnes M. (Agnes Mary)

Sir Howard Grubb, moreover, set up, in 1882, a kind of siderostat at the Crawford Observatory, Cork.

From A Popular History of Astronomy During the Nineteenth Century Fourth Edition by Clerke, Agnes M. (Agnes Mary)

The largest siderostat in the world is the Paris 50-inch refractor, which formed the chief attraction of the Palais d'Optique at the Exhibition of 1900.

From A Popular History of Astronomy During the Nineteenth Century Fourth Edition by Clerke, Agnes M. (Agnes Mary)