Online Encyclopedia Search Tool

Your Online Encyclopedia


Online Encylopedia and Dictionary Research Site

Online Encyclopedia Free Search Online Encyclopedia Search    Online Encyclopedia Browse    welcome to our free dictionary for your research of every kind

Online Encyclopedia


A Heliostat is a device that tracks the movement of the sun. Its most common use is to direct a mirror which reflects sunlight onto a fixed spot. It was a key instrument used in surveying, allowing the accurate observation of a known point from a distance.

It is also used in Solar Energy collectors as well as Solar observatories.

The simplest devices would use a clockwork mechanism to turn the mirror in synchronisation with the roatation of the Earth. More complex devices need to compensate for the changing elevation of the Sun throughout a Solar year.

Last updated: 02-25-2005 20:49:10