- 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.
Origin of siderostat
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for siderostat
The telescope was housed at the Exhibition in a long gallery pointing due north and south, the siderostat at the north end.
The siderostat, twenty-seven feet high, and as many in length, weighed forty-five tons.
The movable portion of the roof of the building had been slid back, and the mirror of the siderostat stood bared to the sky.
C19: from sidero-, from Latin sidus a star + -stat, on the model of heliostat
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012