The Gravity Probe-A Collection of the UAH Archives has now been indexed and made searchable! Gravity Probe-A, a joint program of the NASA-Marshall Space Flight Center and the Astrophysical Observatory of the Smithsonian Institution, was launched by NASA in June, 1976. It was the first test in space to explore the structure of space and time, and was designed to test the “equivalence principle” part of Einstein’s general theory of relativity. Click here to search the collection by Title, Author or Abstract. You can also download the Finding Guide to the Gravity Probe-A Collection in PDF format.