The first pictures of IO from space were made by the station "Pioneer-11", flying past Jupiter in December 1974. The quality of these images better than what was then available to the telescopes. In March 1979, IO was by "Voyager-1" at the distance of 20 thousand km, and in July - "Voyager-2" at a distance of 1.1 million km, the Spacecraft passed high-quality images of the satellite and conducted a number of measurements. The images of the Voyagers on IO was discovered active volcanism. From December 1995 to September 2003 system studied Jupiter spacecraft Galileo. 35 turns of Galileo around Jupiter 7 were designed to study IO (closest approach - 102 km). By using the Galileo satellite was thoroughly examined and received a lot of new data (particularly high resolution images, the measured magnetic field, etc.). In December 2000, passed by Jupiter Cassini, which has received new data. In February 2007, by Jupiter flew the machine New horizons, who carried out the shooting of IO, which allowed to evaluate the new changes of the satellite surface and get some other data. In CLIFT 53 images (15 of 38 Galileo and Voyager) was built a global backbone network IO, consisting of 502 points and the parameters of figure IO, performed orthorectification and created a global mosaic (Fig. 1), which allowed for the study of topography (Fig. 2) and libration IO. For calculations was used to updated the ephemerides of the SPACECRAFT Galileo, published in 2011 (http://naif.jpl.nasa.gov/), which allowed to significantly improve the accuracy of determination of coordinates.
Fig. 1. Mosaic of IO, built in MExLab, in the projection of latitude-longitude with the horizontals drawn through the 5 km
Fig. 2. Digital elevation model of the mountain portion of the surface of IO, built in stereo images. Big top shows an area cut from the mosaic.