Publisher Desc.  Io and Europa are the two most interesting and scientifically important for several reasons. Io is the most volcanically active body in the solar system due to the literal stretching of the planets solid surface during orbit around Jupiter's massive gravity. This pulling and stretching of the crust creates heat and volcanic activity, driving away any water. This piece is designed to convey both the isolation of Io and also its aggravated geological force. On its surface volcanoes produces plumes of sulfur and sulfur dioxide.