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A Farewell to Jupiter

Photojournal: PIA03451
NASA's Saturn-bound Cassini spacecraft looked back to see Jupiter as a thinning crescent 17 days after its closest approach to the giant planet. This sort of view, from the dark side of an outer planet, is not possible from Earth.
A crescent Io, innermost of Jupiter's four large moons, appears to the left of Jupiter.
Credit
NASA/JPL/University of Arizona