The dial was designed with the aid of a computer program written by David Potter. The program solves Kepler’s Laws to determine the location of the earth in its orbit, and then determines the altitude and azimuth angle of the sun at the observer’s latitude and longitude at the particular date and time. It then calculates the location of the projection of the rays on the vestibule walls. The dial was designed “from scratch” by the designer.

The entrance tower was designed by architect Paul Hutton as a "sun tower". He proportioned the tower so the sun's rays would be at the bottom of the wall at solar noon at summer solstice and at the top of the wall at solar noon at winter solstice. Paul and Dave Potter, a science teacher at Kent Denver, collaborated on the final design, which includes an embedded reference grid that reveals the sun's altitude and azimuth angle (in addition to the time and date.)