a device consisting of a mirror slowly revolved by clockwork so as to reflect the sun's rays continuously in a fixed direction
Origin of heliostat; from Modern Latin heliostata: see helio- and amp; -stat
An instrument in which a mirror is automatically moved so that it reflects sunlight in a constant direction. It is used with a pyrheliometer to make continuous measurements of solar radiation.
- A device that includes a plane mirror which turns so as to keep reflecting sunlight toward a predetermined target, compensating for the sun's apparent motions in the sky. The target may be a physical object, distant from the heliostat, or a direction in space, and is almost always stationary relative to the heliostat, so the light is reflected in a fixed direction.