3. The Unisphere is the Largest Global Structure (and the Mystery of The Rings)
The Unisphere is the largest globular structure built by man, weighing 700,000 pounds with a base that weighs 200,000 pounds. The Queens Chronicle also reports that is the “largest structure fabricated entirely with stainless steel,” and the sculpture itself was donated by U.S. Steel as the symbol for the 1964 World’s Fair.
Of more dispute are the rings on the Unisphere. The official NYC Landmarks Preservation report writes that the stainless steel rings denote the first manmade satellites. The book Meet Me at the Fair: A World’s Fair Reader states that the three rings supposedly represent the flightpaths of three historical moments in space travel: the first of the Russian, Yuri Gagarin, who was the first person to fly in space; that of John Glenn, the first American to orbit the earth; and the path of Telstar, the first communications satellite, launched in 1962. However, in the book, this fact is mistakenly attributed to the same NYC Landmarks Preservation report (above) by footnote, and the Wikipedia entry also echoes this (likely) misinformation. Many popular online sources also ascribe to the Gagarin/Glenn/Telstar theory.
To support the satellite ring theory, there is also a letter (available in the New York World’s Fair archive at the New York Public Library) from Unisphere designer Gilmore D. Clarke to Robert Moses that explained the original intent: to have rings representing each satellite in orbit–but there were too many for the sculpture and the three rings became symbolic representations of the satellites. There was also a study done that proposed moving and lighted satellites on the Unisphere, but that was also deemed too expensive.