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Effects of wind loads

Vibrations and inaccuracies of the guiding system are a major source of loss of performance of a telescope following the course of a sky object during the required exposure time.

Modern telescopes benefit from the progress in low-friction bearings and electro-mechanic drives. Also the performance of active loop control systems has progressed very close to the theoretical limits. Thus the guiding accuracy of a modern telescope is mainly limited only by the mechanical turbulence of the wind acting on the telescope structure. A first quantification of the perturbation brought by the wind will be given by the portion of the energy density spectrum at frequencies greater than the bandwidth of the guiding loop.

Lorenzo Zago,, Sun Feb 26 22:57:31 GMT+0100 1995