Dylan Thuras is a guest blogger on Boing Boing. Dylan is a travel blogger and the co-founder of the Atlas Obscura: A Compendium of the World's Wonders, Curiosities, and Esoterica, with Joshua Foer.
Recently the most perfect spheres in the world were created as an answer to the "kilogram problem." Made to replace a chunk of platinum and iridium that has defined how much a kilogram weighs for 120 years (the weight of the metal has been changing ever so slowly ) the spheres are about the size of a melon and almost perfectly round. They are likely the most perfectly spherical objects on the planet.
"If you were to blow up our spheres to the size of the Earth, you would see a small ripple in the smoothness of about 12 to 15 mm, and a variation of only 3 to 5 metres in the roundness"
With this in mind we present you a collection of a few of the more interesting spheres found around the world.
Sweden Solar System: The world's largest model of our planetary system centered around the largest spherical building in the world.
The Mapparium: An three story inside-out glass globe built in 1935.
The Sudbury Neutrino Observatory: A gigantic spherical neutrino detector built into the largest man made underground cavity in the world.
Costa Rican Stone Spheres: Mysterious spherical rock formations from an earlier era.
Paris Sewer Museum: Giant wooden balls helped keep the Parisian sewers clean.
The Republic of Kugelmugel: A spherical "micro-nation" in the heart of Vienna.