In this pressurized balloon gondola, on November 11, 1935, Capt. Albert Stevens and Capt. Orvil Anderson of the U.S. Army Air Corps reached 22,065 meters (72,395 feet), a world altitude record that would stand for 20 years.
The Explorer II balloon boasted a capacity of 104,772 cubic meters (3,700,000 cubic feet) of helium. The 3-meter (9-foot) spherical gondola is made of welded magnesium/aluminum alloy sections, weighs 290 kilograms (640 pounds), and can carry a payload of 680 kilograms (1,500 pounds).
Gift of the National Geographic Society