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Sun Shadow Investigation Project

Welcome to the Sun Shadow Investigation Project.

    Please take part in a science collaboration as a participant in a global Eratosthenes Project. The Eratosthenes Project is named in honor of Eratosthenes of Cyrene (now known as Libya, North Africa). Erastothenes (275-195 B.C.) was a scholar, and for many years was the Director of the Library of Alexandria. Eratosthenes made many contributions to Science and Mathematics but it was his accurate measurement of the Earth's circumference, using differences in the Sun's altitude and shadows between two different locations, that we seem to remember him mostly for.

Colegio Menor San Francisco de Quito     During the week of the 2004 September Equinox, and especially on the Equinox day the 22nd,  students from both the southern and northern hemispheres will measure the mid-day altitude of the Sun and combine this with measurements made by faculty and students at Colegio Menor San Francisco de Quito. the host school for SunShIP, to determine the circumference of the Earth.

Measuring the Sun's Altitude On the Equator at Mitad del Mundo     Last year (2003) while my wife and I were in Ecuador we went to Mitad del Mundo Museum and measured the altitude of the Sun from directly on the equator (yellow line) and then posted that information.
Click on the picture on the right to read and see a journal of our trip around Ecuador.

    Interested in reaching new heights? While in Ecuador my son and I will be attempting to summit two mountains, Illinizi North (16 818 feet) and Cotopaxi (19 347 feet). We will share our experiences with video and pictures following the climbs. Check the links page for a link to some pictures, borrowed from web sites, of the two mountains.

Guest Map     Check the FAQ page for more information about participating in the project, and also look at the Links page for lessons, activities and other resources relevant to the investigation of our Sun.

    Please add your location to the Guest Map. Use the button on the FAQ page

Thank you in advance for your interest.

Clear Skies...

Bob Riddle


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