Circular agricultural fields in Morgan County, Colorado, USA

© Jim Wark/Getty Image

It’s 3.14159 Day. Going full circle for maths

It’s Pi Day, the day we celebrate the mathematical constant π. This day was chosen since today’s date expressed numerically (in US format) matches the number’s first digits, 3.14. Pi represents the ratio of a circle’s circumference to its diameter. It can be used to compute the area and circumference of a circle, such as the crop patterns we're looking at here in the US state of Colorado. (Who said maths wasn't useful in the real world?) Many towns, schools and museums mark the day with festivities based around mathematics and, of course, serving pie. We can’t think of a more delicious way to study geometry.