Io and Jupiter

Description

Io, the round object at left, is one of the largest of the moons of Jupiter. Clouds in Jupiter’s atmosphere form the backdrop to this image. Lo has a diameter of 3642 kilometres, but Jupiter, the solar system’s largest planet, dwarfs its moon, with a diameter of 142,984 kilometres. Io is the innermost of the four Galilean moons, orbiting Jupiter at a distance of 350,000 kilometres from its cloudtops. Image obtained on 1 January 2001 by Cassini’s Imaging Science Subsystem (ISS). (Photo by Science Photo Library)