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Welcome to the Sun Shadow Investigation Project.

You are invited to 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.

mid-day 22 September 2004 - Quito EcuadorOn the day of the 2005 September equinox, September 22  (2223 U.T.), (or during the week before or after), participating students from both the southern and northern hemispheres will measure the mid-day altitude of the Sun and take pictures of mid-day shadow at their location. This mid-day measurement will be used by the students to determine the circumference of the Earth, while the pictures will be sent to the SunShIP web site for a display of mid-day shadows from various latitudes. 

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.

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

Taking a Break at Ilinizi North I will be in Ecuador from the 14th through the 30th. After the 24th I will be away from 'civilization' while climbing and thus will not have access to Internet until the 29th, or when I get home on the 30th. So any data sent after the 24th will not be forwarded to Brian to send out certificates until my return. The same for any pictures sent. I will post these as soon as I can after my return.

See some pictures from my mountaineering in Ecuador with Edison Ona. Click on the Ecuador 2005 link.

Thank you in advance for your interest.

Clear Skies...

Bob Riddle

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