Dolmen of Sorginetxe, Basque Country, Alava, Spain
© David Herraez Calzada/plainpictur
Pi in the sky. Celebrating Pi Day
Calculating the ratio of a circle's circumference to its diameter is as easy as pi. Today is Pi Day, an event that celebrates this mathematical constant. This date was chosen because 3, 1 and 4 are the first three significant figures of pi (π) when it is written out. Pi is an irrational number, which means that it can't be written as a fraction. When written out, its decimal representation goes on infinitely without repeating. The oldest attempts to calculate pi date back to ancient Babylon and Egypt, around 1,900 BCE.
Related Images
Cefalù on the Tyrrhenian coast of Sicily, Italy
For Waitangi Day, the Pancake Rocks on New Zealand’s South Island
Loup of Fintry waterfall on the River Endrick, Scotland
Firefall at Horsetail Fall, Yosemite National Park, California, USA
La Digue, an island in the Seychelles
Mua Caves in the Ninh Bình province of Vietnam
Full moon rising over Dunnottar Castle near Stonehaven on the north-east coast of Scotland
Wildflowers in bloom at Lost Dutchman State Park in Arizona, USA
Bing Today Images
Wat Phra Ngam, Ayutthaya Historical Park, Thailand
Mar 14, 2024
Labyrinth in Cyherbia Botanical Park, Cyprus
Mar 14, 2023
Lanyon Quoit burial chamber, Cornwall
Mar 14, 2022
The Circle Bridge in Copenhagen, Denmark
Mar 14, 2020
Enhanced image of a cross section of a pine stem
Mar 14, 2017
