Jupiter from Io,artwork. Io,the third largest of the moons of the gas giant planet Jupiter (planetary limb at upper centre),orbits the planet at a distance of 422,000 kilometres. The gravity of Jupiter and other moons,create huge tides,powering Io's volcanoes (one erupting at left). These can eject sulphur over 100 kilometres into space. Hundreds of active volcanoes on Io make it the most geologically active body in the solar system. Jupiter,the largest planet in the solar system,has an equatorial diameter of 142,984 kilometres |