Member of the Field Artillery Meteorological and Topographical Detachment, U.S. 8th Army prepares to release a radiosonde into the night in December 1952. A radiosonde consisted of a battery-powered instrument in a white box. It is attached to a helium-filled weather balloon and released into the air. The instrument measures temperature, humidity, and air pressure and radios the information to a ground receiver. At a certain altitude, the balloon pops and the radiosonde floats back to earth suspended by a red parachute.