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rings of Jupiter





Jupiter rings
Jupiter has a faint ring system with four main components: the halo ring, the main ring, and the two gossamer rings; it was first detected by Voyager 1.

The main ring encompasses the orbits of the two innermost moons Adrastea and Metis, and at its inner edge merges into the halo, a broad, faint torus of material extending halfway from the main ring to Jupiter's cloud-tops. Just outside the main ring are the broad and extremely faint gossamer rings, one bounded by the orbit of Amalthea, the other by the orbit of Thebe.

In 1996-97 the Galileo spacecraft recorded events showing how Jupiter's rings are still being formed. Comet and meteor debris, accelerated by Jupiter's powerful gravitational field, smash into the inner four moons flinging dark-red surface material into space. Galileo took pictures of the red dust coming off Amalthea and Thebe, the two moons orbiting in the gossamer ring. The dust travels so fast that it escapes the minute gravitational fields of the tiny moons and goes into orbit. It then enters the gossamer rings and adds to the collection that has been accumulating there over billions of years. A similar process involving Adrastea and Metis are thought to supply the particles for the main and halo rings.


name inner radius (km) outer radius (km) width (km)
halo ring 100,000 122,800 22,800
main ring 122,800 129,100 6,300
gossamer ring 129,100 250,000+ 121,000+


Related category

   • PLANETS AND MOONS