On 28 November 1959 the Stratolab IV balloon ascended to 81,000 feet with a 16 inch Schmidt infra red telescope attached to the top of the gondola. The 2 million cu.ft. balloon was made of polyethylene.
Inside were pilots Malcolm Ross and Charles Moore who used the telescope to perform spectrograph analysis of the water vapour in the atmosphere of Venus thus demonstrating that an observatory can be taken aloft.
Charles Moore is remembered for making the first manned flight beneath a polyethylene balloon on 3 November 1949. Malcolm Ross flew all five flights of the Stratolab programme and went on to pilot more high altitude balloon flights to to accomplish research required for the manned rocket program to follow.