Star clock
From Wikipedia, the free encyclopedia
A star clock is a method of using the stars to determine the time. Some methods require no tools; others use an astrolabe and a planisphere.
A clock's regulator can be adjusted so that it keeps the Mean Sidereal Time rate. When it is then set to an observer's Local Mean Sidereal Time then a star will transit the meridian (passing directly north or south) at the sidereal time of the star's Right Ascension.
[edit] See also
[edit] External links
- Telling Time by Sun and Stars by John P. Pratt
- Inquiry.net