en.wikipedia.org/wiki/Eratosthenes

Eratosthenes of Cyrene was a Greek mathematician, geographer, poet,
astronomer, and music .... Eratosthenes calculated the **circumference** of the **Earth**
without leaving Egypt. He knew that at local noon on the summer solstice in
Syene ...

en.wikipedia.org/wiki/Earth

**Earth** is the third planet from the Sun and the only object in the Universe known to
harbor life. ... Circumference. 40075.017 km equatorial (24901.461 mi) ...

www.khanacademy.org/partner-content/nasa/measuringuniverse/measure-the-solarsystem/v/eratosthenes_measures_earth

If he carried out the calculation with the Greek stade, he would have miscalculate
the **circumference** of the **Earth** by about 16%. However, he would have been ...

www.todayifoundout.com/index.php/2014/01/amazing-eratosthenes

Jan 1, 2014 **...** Today I found out about a man who fairly accurately estimated the **circumference**
of the **Earth** well over 2,000 years ago: Eratosthenes of ...

www.space.com/17638-how-big-is-earth.html

Sep 15, 2017 **...** **Earth** is the fifth largest planet in the solar system and the densest. Diameter of
**Earth**, **circumference**, mass & volume explained.

www.thoughtco.com/essential-facts-about-the-planet-earth-1435092

Apr 24, 2017 **...** Here you will find a listing of essential facts about planet **Earth**, the home to all of
humanity. The **circumference** of the **Earth** at the equator: ...

www.universetoday.com/26461/circumference-of-the-earth

Mar 2, 2009 **...** The **circumference** of the **Earth** in kilometers is 40,075 km, and the **circumference**
of the **Earth** in miles is 24,901. In other words, if you could ...

www.dummies.com/education/math/geometry/how-to-determine-the-earths-circumference

By Mark Ryan. You can figure out the **earth's circumference** using a geometric
formula that's over 2,000 years old! Contrary to popular belief, Christopher ...

www.lyberty.com/encyc/articles/earth.html

**What is the circumference** of the **Earth**? How far around is the **Earth**? The
average radius of the **Earth** is 3,959 miles (6,374 kilometers). The equitorial
diameter of ...