1. Measuring the radius of the Earth THE ERASTOSTHENES’ METHOD Scuola Media Statale “G.G. Belli” - Rome Class 2H Teacher: Leonarda Fucili 22 September 2009
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4. The location : ROME the astronomical terrace of our school 41° 54’ 57’’N 12° 27’ 52’’E
17. 3. Distance Rome – Equator GOOGLE EARTH 4.628,94 KM
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19. THE RATIO Sun’s parallel rays Equator Rome Rome/equator distance = about 4800 Km 42 ° 42 ° 42 ° 360 ° meridian
20. THE CALCULATION (approximation in latitude: 1 degree) 360 degs 42 degs = About 4800 Km x X = circumference of the Earth = about 41.142 Km
21. Reducing uncertainties for our Earth radius value Local Latitude : 41° 54’ 57’’N Distance Rome/ Equator: 4.628,94 KM 360 ° : 41° 54’ 57’’N = 1.296.000” : 150.897” = 8,588 4.628,94 KM x 8,588 = 39.756 Km