Jupiter and two of its moons, photographed from a distance of 28.4 million kilometres by the Voyager 1 spacecraft on February 5, 1979. Jupiter's inner- most satellite, Io, can be seen against the planet's disc; at the far right of the picture is Europa, another of Jupiter's four Galilean satellites (so called because they were discovered by Galileo). Jupiter's atmosphere consists of colourful, swirling bands of cloud; it is domin- ated by the Great Red Spot, visible towards bottom left, which is a giant, circulating atmospheric disturbance. The original print, before being cropped during duping, also shows the satellite Callisto very faintly at the very bottom of the photo. The photo