Eratosthenes measures the earth. It was around 250 BCE when Eratosthenes was a librarian in the famous library of Alexandria He discovered in his reading that there was a yearly festival in the town ...

Summer Ash is The Rachel Maddow Show's in-house astrophysicist. She blogs at Newtonianism for the Ladies.

An ancient Greek mathematician calculated the Earth's circumference without ever leaving home.

Eratosthenes actually had it easy, he already knew of a nearby city (Syene) where the sun was directly overhead at midday on one day of the year - the summer solstice - meaning that all he had to ...

I ended up with just enough time over the weekend to pull together a quick project. I implemented the Sieve-of-Eratosthenes on an ARM chip. If you haven’t heard of the Sieve of Eratosthenes then ...

And Eratosthenes probably already knew that. The idea of a spherical Earth was floated around by Pythagoras around 500 BC and validated by Aristotle a couple centuries later.

IN Sky and Telescope of September, under the heading “Saluting an Astronomer”, Joseph R. Habes has an article which describes the method adopted by Eratosthenes for measuring the circumference ...

I implemented the Sieve-of-Eratosthenes on an ARM chip. If you haven’t heard of the Sieve of Eratosthenes then you really need to work your way through Project Euler.

Ancient Greek mathematician Eratosthenes devised a way to find prime numbers PRIME numbers may have been studied for over 2000 years, but there is always something new to learn. A method for ...

Eratosthenes estimates Earth’s girth It is now well established that the Earth’s equatorial circumference is 40,030 km. But have you ever wondered when the first such measurement was carried ...