The Millennium Sundial
Posted by: TeamTGF
S 26° 00.994 E 027° 44.058
35J E 573477 N 7122274
This Sundial can be found in the Cradle of Humankind.
Waymark Code: WM17Z3
Location: Gauteng, South Africa
Date Posted: 02/17/2007
Views: 32
The sundial was designed by Dr Mike Gaylard of the Hartebeesthoek Radio Astronomy Observatory, specifically for the latitude and longitude of Sterkfontein. A movable stick known as a "gnomon" is placed vertically on the engraved granite surface, and the time for a particular day of the year can be read from the position of the shadow cast by the gnomon, across the "Time Line". In order to give an accurate time of day, the position of the gnomon for any particular day changes in the course of a year, taking into account seasonal changes associated with the shape of the earth’s orbit around the sun, and the tilt of the earth’s axis. The gnomon is moved to a new position each day, along the figure-of-eight path known as an "analemma" or "Date Line", which allows for these effects.
Sundial Type: Analemmatic - Vertical gnomon with elliptical dial
Related Web Site: Not listed
|
Visit Instructions:
Only one log per location per person. You should log your own waymarked sundials as well.
GPS in photo optional.