New Planet Gnomon


General Description

This program simulates the shadow cast by a gnomon over the course of a day for any day of the year on a fictitious planet. The user can select from three different locations on the planet. The model is constructed on the basis of a circular planetary orbit with the Sun at the center (or, equivalently, a circular orbit for the Sun with the planet at the center). The user can make measurements to determine the latitude and relative longitude of all three locations. Since two of the locations have the same longitude, the user can determine the radius of the planet if given the distance between these two locations. The user can also determine the obliquity of the ecliptic, the number of hours in a solar day, the number of solar days in a tropical year, the dates of the solstices and equinoxes, and the latitudes for the arctic/antarctic circles and the tropics.

Gnomon Frame



Version History


Todd K. Timberlake (ttimberlake@berry.edu)