In this activity, learners will measure the length of a shadow and use the distance from the equator to calculate the circumference of the earth. Note: This experiment can only be done at solar noon twice a year; at the spring and autumnal equinox. These are the two times the sun is directly over the equator. You can do this experiment one or two days before or after the equinox to work around cloudy days. This resource includes a corollary story related to Christopher Columbus and his journey to India as well as winter and summer safety tips.


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Informal Education,Data Analysis,equinox,NSDL,equator,NSDL_SetSpec_ncs-NSDL-COLLECTION-000-003-112-056,Reflection and Refraction,Space Science,Problem Solving,Mathematics,General,Earth, Moon and Sun,Circles,Size and Scale,Data Collection,Equations and Inequalities,Upper Elementary,oai:nsdl.org:2200/20110926115558341T,Eratosthenes,Atmospheric science,Solid Geometry,Rotation Motion,Seasons,Variables and Expressions,Number and Operations,Middle School,Formulating Explanations,Geometry,Measurement,Plane Geometry,Elementary School,angles,Weather and Climate,Conducting Investigations,Chemistry,Physics,shadows,circumference,General science,geometry,solar noon,Christopher Columbus,Earth system science,Geoscience,Sunlight and Color,High School,Space science,sun,Physical science,Education,Gathering Data,Light and Optics



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