Pi Day Celebrates Math Constant's Widespread Impact

From space exploration to cancer research, pi is embedded in everyday science and technology

Mar. 14, 2026 at 3:12pm by Ben Kaplan

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As people celebrate Pi Day on March 14, the mathematical constant pi continues to be an integral part of everyday life for scientists and engineers. Pi is used in a wide range of applications, from calculating spacecraft motion and propulsion systems to developing new medical tests and technologies. The holiday was created in 1988 by a physicist at the Exploratorium science museum in San Francisco, and has grown into an annual celebration featuring a procession of people carrying digits of pi.

Why it matters

Pi is a fundamental mathematical concept that is woven into the fabric of science and technology. Understanding and applying pi is crucial for advancements in fields like aerospace engineering, biomedical research, and fluid dynamics. Celebrating Pi Day helps raise awareness of the importance of math and science in our everyday lives.

The details

Pi, which represents the ratio of a circle's circumference to its diameter, is used in countless scientific and engineering formulas. In aerospace engineering, pi is essential for calculating spacecraft motion, materials, and propulsion systems. In bioengineering, pi is used to create tiny polymer droplets that act as "test tubes" for studying cells and developing new medical tests. Pi is also crucial for understanding fluid dynamics, like the flow of liquids in COVID-19 tests. While pi may seem like an abstract mathematical concept, it is deeply embedded in the technologies and innovations that shape our world.

  • Pi Day is celebrated annually on March 14 (3.14), the date that represents the first three digits of the mathematical constant.
  • The Pi Day celebration at the Exploratorium science museum in San Francisco began in 1988 as a small staff event featuring pie.
  • The Exploratorium's Pi Day celebration has grown over the years, now featuring hundreds of visitors marching in a procession carrying digits of pi.

The players

Larry Shaw

A physicist at the Exploratorium science museum in San Francisco who created Pi Day in 1988.

Sam Sharkland

The program director of public programs at the Exploratorium, who worked with Larry Shaw before his death in 2017.

Artur Davoyan

A professor of mechanical and aerospace engineering at the University of California, Los Angeles, whose research looks at creating new propulsion systems for space exploration.

Dino Di Carlo

The chair of the bioengineering department at the UCLA Samueli School of Engineering, who conducts research on using tiny polymer droplets to study cells and develop new medical tests.

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What they’re saying

“He had a very open and expansive view of the world and saw an opportunity with this number, mathematical concept, to invite people into the joy of mathematical learning.”

— Sam Sharkland, program director of public programs at the Exploratorium (nbcnews.com)

“Say aliens send something to us, something that we don't know how to deal with. So the very first thing that you would do, you would try to split it into simple functions... and turns out that when you do this operation, you will naturally have pis in it.”

— Artur Davoyan, professor of mechanical and aerospace engineering at the University of California, Los Angeles (nbcnews.com)

“As an engineer and scientist, (pi) is just a part of life. Maybe I've taken it for granted.”

— Dino Di Carlo, chair of the bioengineering department at the UCLA Samueli School of Engineering (nbcnews.com)

The takeaway

Pi is a fundamental mathematical constant that is deeply embedded in the scientific and technological advancements that shape our world, from space exploration to medical research. Celebrating Pi Day helps raise awareness of the importance of math and science in our everyday lives and the ongoing discoveries and innovations that are made possible by understanding and applying this ubiquitous mathematical concept.