<P> The physical and orbital characteristics of the moons vary widely . The four Galileans are all over 3,100 kilometres ( 1,900 mi ) in diameter ; the largest Galilean , Ganymede , is the ninth largest object in the Solar System , after the Sun and seven of the planets , Ganymede being larger than Mercury . All other Jovian moons are less than 250 kilometres ( 160 mi ) in diameter , with most barely exceeding 5 kilometres ( 3.1 mi ) . Their orbital shapes range from nearly perfectly circular to highly eccentric and inclined , and many revolve in the direction opposite to Jupiter 's spin ( retrograde motion ) . Orbital periods range from seven hours ( taking less time than Jupiter does to spin around its axis ) , to some three thousand times more ( almost three Earth years ) . </P>
<P> The physical and orbital characteristics of the moons vary widely . The four Galileans are all over 3,100 kilometres ( 1,900 mi ) in diameter ; the largest Galilean , Ganymede , is the ninth largest object in the Solar System , after the Sun and seven of the planets , Ganymede being larger than Mercury . All other Jovian moons are less than 250 kilometres ( 160 mi ) in diameter , with most barely exceeding 5 kilometres ( 3.1 mi ) . Their orbital shapes range from nearly perfectly circular to highly eccentric and inclined , and many revolve in the direction opposite to Jupiter 's spin ( retrograde motion ) . Orbital periods range from seven hours ( taking less time than Jupiter does to spin around its axis ) , to some three thousand times more ( almost three Earth years ) . </P>
which of jupiter 's moons is the largest in the solar system
which of jupiter 's moons is the largest in the solar system
Ganymede
Ganymede