Happy Pi Day! Yes, it is March 14, or 3-14, as in Pi, or *π*, being 3.14 when rounded to two decimals. This year is an extra special Pi Day, since it is 3-14-16 and Pi is 3.1416 when rounded to four decimals.

It is good to have a day on which a mathematical idea like Pi is celebrated. Astronomy involves a lot of mathematical ideas. Unfortunately, mathematics tends to be dismissed as something no one would actually care to think about and understand. Consider the story NPR ran a while back about math teacher Jake Scott of Montgomery Blair High School in Silver Spring, Maryland. Mr. Scott sometimes teaches under the persona of the rapper “2 Pi.” About this NPR’s David Greene stated, “His alias, ‘2 Pi,’ comes from a math formula, one that I’m not even going to *try* to explain.”^{*} That beyond-explanation formula is one that defines Pi; it is the formula relating the Circumference *C* of a circle to its Radius *R*: ** C=2πR**. This basic mathematical idea was characterized as beyond explanation even though NPR has an audience that gets described as being talented and curious, well-educated and intellectual. Even to such an audience mathematics is dismissed as something no one would care to think about and understand.

But mathematics is not dismissed on The Catholic Astronomer! Mathematics is a great way to think about the world. So much astronomy rests on mathematics. Dismiss mathematics like “2 Pi” as beyond explanation, and you implicitly dismiss a lot of astronomy as beyond explanation, too. And when you are thinking of science as being beyond explanation, you are thinking of it more as magic than as science.

So celebrate Pi Day, and be looking for some Catholic Astronomer posts that focus on explaining how we know what we know in astronomy, and how we can learn so much through reasoning with mathematical ideas. This stuff is not beyond explanation. Most of it isn’t even much beyond Pi.

^{*}“*2 Pi: Rhymes And Radii**” by David Greene, at the 1:30 mark. A **transcript of the story** is also available through station WRFK-FM. *