Explorer 6, or S-2, was a NASA satellite, launched on 7 August 1959, at 14:24:20 GMT. It was a small, spherical satellite designed to study trapped radiation of various energies, galactic cosmic rays, geomagnetism, radio propagation in the upper atmosphere, and the flux of micrometeorites. It also tested a scanning device designed for photographing the Earth's cloud cover. On 14 August 1959, Explorer 6 took the first photos of Earth from a satellite.