Biruni's measurement of the Earth

At the beginning of the 11th century, Biruni measured the Earth with a precision not surpassed in the west until the 16th century. This illustration shows how the 34′ dip of the horizon that he says he observed from the top of a hill near Nandana Fort is extremely close to that which can be seen from a nearby hill, thus identifying its location. It also illustrates why he got the height of this hill as 652 cubits and 3′18″ (or 321½ m).

 

A. G. Gomez (algomgom@gmail.com)

 
Resource Type
Activity
Tags
air  bending  biruni  dip  earth  horizon  radius  refraction 
Target Group (Age)
19+
Language
English (United Kingdom)
 
 
GeoGebra version
5.0
Views
5839
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