Science & Tech
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The Portsmouth Mine operated from 1912 to 1960 and produced 12,370,260 tons of iron ore in the city of Crosby, Minnesota. On August 19, 1957, a balloon launched from the mine carried Air Force Major David G. Simons 19 miles up into the stratosphere. Sealed inside an aluminum capsule with its own artificial atmosphere, he used a 5 inch telescope and a number of mirrors to observe the earth and stratosphere. The balloon was launched from the bottom of the 350 foot deep pit to avoid surface winds. The balloon and capsule remained aloft for more than 32 hours before landing near Elm Lake on the North Dakota-South Dakota border on August 20, 1957. The flight was intended to determine man's reactions at heights never before reached, and its findings helped pave the way for future ventures into space by rockets and planes.
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Crosby, Minnesota · United States
