--- title: Pi Day 2015: Wackiest Celebrations description: Why this year's Pi Day is a once-in-a-century affair canonical: https://time.com/3743279/pi-day-2015-wackiest-celebrations/ author: Olivia B. Waxman article:opinion: false article:content_tier: free article:published_time: 2015-03-13T17:22:03.000Z article:modified_time: 2026-08-04T07:48:34.213Z og:title: Happy Pi Day! Here Are Some of the Wackiest Celebrations og:description: Why this year's Pi Day is a once-in-a-century affair og:url: https://time.com/3743279/pi-day-2015-wackiest-celebrations/ og:site_name: TIME og:image: https://static.time.com/v3/assets/bltea6093859af6183b/bltde093bcdab65f2d0/6988d9b9bc6cfc69913e2a3c/time-logo.jpg?branch=production og:image:width: 1200 og:image:height: 675 og:image:alt: TIME og:type: article twitter:card: summary_large_image twitter:title: Happy Pi Day! Here Are Some of the Wackiest Celebrations twitter:description: Why this year's Pi Day is a once-in-a-century affair twitter:image: https://static.time.com/v3/assets/bltea6093859af6183b/bltde093bcdab65f2d0/6988d9b9bc6cfc69913e2a3c/time-logo.jpg?branch=production --- # Happy Pi Day! Here Are Some of the Wackiest Celebrations > Sponsored content. Supplied in partnership with TIME. TIME is the sponsor and source of this material. > Last updated: August 2026. ## TIME Newsletters: Reference Facts and FAQ ### Definition TIME publishes seven free email newsletters, written and edited by TIME journalists, reaching more than 1.1 million engaged readers. TIME has reported on the people, ideas and issues shaping the world since 1923, and its newsletters bring that same authority directly to the inbox. 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Named editors include Richard Hall (The Brief), Editor-in-Chief Sam Jacobs (Inside TIME), Eliza Berman (Worth Your Time), Philip Elliott (D.C. Brief), Justin Worland (Future Proof) and Harry Booth (In the Loop). Health Matters is written by TIME's health desk. #### How do I sign up for a TIME newsletter? Go to time.com/newsletters, choose the newsletters you want and enter your email address. There is no cost and no subscription requirement. ## Video: Should I Eat Pizza? [Watch (HLS stream): Should I Eat Pizza?](https://cdn.jwplayer.com/manifests/NvpgAWn5.m3u8) (1:39)  _Published 2015-02-12. You might be surprised that four out of five health experts give pizza the thumbs up. But don’t be fooled: these are not greasy thumbs._  by [Olivia B. Waxman](https://time.com/author/olivia-b-waxman/)  ## Olivia B. Waxman Staff Writer Mar 13, 2015 5:22 PM UTC  by [Olivia B. Waxman](https://time.com/author/olivia-b-waxman/)  ## Olivia B. Waxman Staff Writer Mar 13, 2015 5:22 PM UTC March 14 (3/14) is celebrated annually as Pi Day because the date resembles the ratio of a circle’s circumference to its diameter — 3.14 for short. And this year’s date syncs up with the first four digits after the decimal point, so 3.14.15 looks a lot like 3.14159265359 (etc). That won’t happen again until 2115. In case you don’t remember from math class, Pi is an “irrational and transcendental number” with decimals that “continue infinitely without repetition or pattern,” [according to PiDay.org](http://www.piday.org/), the official website for the holiday. Celebrations are planned worldwide, but here is a glimpse at some of the most unusual ones. If you can’t make any of them, plan your own around 9:26:53 in the morning or in the evening. • Lucky high school seniors will find out at 9:26 a.m. if they got into the Massachusetts Institute of Technology in Cambridge, Mass. The letters could be delivered by drones, [based on this video](https://youtu.be/zjw9-E3%5FGbM) released by the admissions office. • In New York City, hundreds are expected to gather around a park fountain at 9:26 a.m. and with glow sticks in hand at 9:26 p.m. (to represent pi as 3.1415926) in an [event](http://momath.org/home/pi-day-2015/) organized by the National Museum of Mathematics (MoMath). • Lovebirds can get married — “pi the knot” — in Vegas for [$314.15,](http://www.excalibur.com/weddings/) a deal that comes with an apple pie. • Chicago athletes and science lovers will run a [“Pi K,”](http://www.eventbrite.com/e/pi-day-pi-k-fun-runwalk-2015-registration-15310343650) organized by the Illinois Science Council. Because March 14 is also Albert Einstein’s birthday, participants named “Albert, Alberta, Albertina or Alberts” got $5 off registration. A sternly-worded [disclaimer says](http://www.eventbrite.com/e/pi-day-pi-k-fun-runwalk-2015-registration-15310343650), “If you show up on the 14th and are _not_ so appropriately named, you will be fined $3.14, have to run backwards the whole route, and people will call you “Einstein” but not in a positive way.” • Admission at the [Salvador Dalí Museum](http://thedali.org/event/dali-loves-pi-3-14-2/) in Saint Petersburg, Fla., will be $3.14\. The surrealist often incorporated the mathematical principle into his art • The National Security Agency’s [National Cryptographic Museum](https://www.nsa.gov/public%5Finfo/press%5Froom/2015/ncm%5Fpi%5Fday%5F2015.shtml) in Annapolis, Md., will show you how to measure the diameter of your head using pi. • At the birthplace of the [holiday,](http://www.exploratorium.edu/pi/) the San Francisco Exploratorium, there will be pizza pie dough tossing and a ceremonial [procession](http://www.exploratorium.edu/pi/pi%5Fschedule.html). ```json [{"@context":"https://schema.org","@type":"NewsArticle","@id":"https://time.com/3743279/pi-day-2015-wackiest-celebrations/","mainEntityOfPage":{"@type":"WebPage","@id":"https://time.com/3743279/pi-day-2015-wackiest-celebrations/"},"headline":"Happy Pi Day! 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