Π Day · 15 March 06
I totally didn’t know about this phenomenon and thus missed out on one of my favourite things – eating pie – yesterday. Thanks to Dulcie and Karen (my nerdy co-workers) for introducing me to this fabulous day.
March 14, written as 3-14, represents the common three-digit approximation for the number Π: 3.14.
Pi Day is celebrated, on March 14, often at 1:59 p.m. in recognition of the six-digit approximation: 3.14159. Some people who use a 24-hour clock celebrate it at 3:09 p.m. (15:09) instead.
Pi Day is celebrated in a variety of ways: Parties or other observances may be held by mathematics departments in educational institutions. Math or science clubs might gather to consider the role that the number Π has played in their lives and to imagine the world without Π. During such an event, pi celebrants may devise alternative values for Π, play piñata, drink Piña Colada, eat pineapple, listen to the song “Pi” by Kate Bush, or eat pie. The shape of the pie is sometimes square, due to the pronunciation of the equation for the surface area bounded by a circle = Πr2, i.e., “pie are squared.”
Pi Approximation Day may be marked on any of these days:
- July 22, which is written as 22/7 in international (little-endian) date format; 22 divided by 7 is an approximation of Π.
- April 26 (April 25 in a leap year), the day on which planet Earth completes two Astronomical units’ worth of its annual orbit. On this day the total length of Earth’s orbit, divided by the length already traveled, equals π (that is, the Earth has travelled two radians in its orbit).
- December 21 (December 20 in a leap year), the 355th day of the year, at 1:13 p.m., based on the approximation value of 355/113 derived by Zu Chongzhi.
- November 10 (November 9 in a leap year), which is the 314th day of the year on the Gregorian calendar.
— Reva 15 March, 02:24 pm