Jupiter's Gossamer Ring as seen by the Galileo spacecraft New Horizons spacecraft image of Jupiter's faint dust rings Jupiter's faint rings were first discovered by the Voyager 1 spacecraft in , when it looked back at Jupiter and towards the Sun.
They are so faint and tenuous, they are only visible when viewed from behind Jupiter and are lit by the Sun, or directly viewed in the infrared where they faintly glow. Early in its mission to Jupiter, the Galileo spacecraft made observations that provided confirmation on how Jupiter's rings were formed, as the dust was seen to coincide with small moon locations: the two Gossamer rings near the small moons Amalthea and Thebe and the main ring near Adrastea and Metis.
Scientists had long believed that dust coming off of Adrastea and Metis formed the main ring, but were unsure of the origin of the Gossamer rings. Jupiter's clouds, ring and even a moon can be seen in this infrared image taken by the Hubble Space Telescope. The top and bottom edges of the gossamer rings are about two to three times brighter than the body of the rings.
As Amalthea and Thebe move up and down in their orbits around Jupiter's equatorial plane, they pause as they reverse directions at the top and bottom of their paths, Ockert-Bell explained. Particles coming off these moons have similar tilts and are more visible at the upper and lower reaches of the satellites' orbits. The innermost halo ring appears to contain escaped particles from the main ring, Burns said.
The particles are electrically charged and are pushed by Jupiter's enormous electromagnetic force, which causes clouds of particles to "bloom" into a vast cloud slowly drawn down into the planet.
Jupiter's diameter is approximately 86, miles , kilometers. The ring system begins about 55, miles 92, kilometers from Jupiter's center and extends to about , miles , kilometers from the planet. The following are additional facts related to the discovery of the source of the rings of Jupiter, announced by the Galileo spacecraft scientific team at a press conference at Cornell University Sept.
In Voyager 1 obtained the first images of a ring system around Jupiter. The same year, most of the important observations of Jupiter's rings were provided by Voyager 2. In just one image the spacecraft captured a faint outer ring, apparently made up of fine, microscopic particles.
This was named the gossamer ring. The spacecraft also captured images of the Comet Shoemaker-Levy 9 as it hit Jupiter. Galileo arrived at Jupiter on Dec. Its current journey, the Galileo Europa Mission, will continue through Jupiter - The solar system's largest planet and the fifth planet from the sun distance: Rings of Jupiter - Galileo's high-quality images have provided greatly improved information about the rings' structure.
The rings are very tenuous; only about one-millionth of the surface area is covered, and the rings contain many particles of microscopic size. Gossamer ring - The ring actually consists of two faint, fairly uniform rings, one enclosing the other, visibly spreading from the outer boundary of the main ring and fading somewhere beyond , kilometers , miles from the center of Jupiter, at Thebe's orbit.
The denser, enclosed gossamer ring extends radially inward from Amalthea's orbit at , kilometers , from Jupiter's center, while the fainter ring is situated interior to Thebe's orbit at , kilometers , miles.
As Amalthea's orbit is crossed, the ring's brightness drops to one-fifth, while near Thebe's path the drop is by a factor of three. Both rings have cross-sections that are crudely rectangular. A striking feature of both rings is that each is banded with top and lower edges brighter than the centers.
Main Ring - The brightest of the Jovian rings reaches from the halo's outer boundary across 6, kilometers 4, miles to , kilometers 80, miles just interior to Adrastea's orbit at , kilometers. Hamilton and German co-author Harald Kruger studied impact data on dust grain sizes, speeds and orbital orientations taken by Galileo as it crossed the rings in preparation for its deliberate death plunge into the planet.
Kruger analyzed the new data set and Hamilton created computer models that matched dust and imaging data on Jupiter's rings and explained the observed eccentricities. The new understanding can be applied to the rings of Saturn, Uranus and Neptune, too, but the effects are more pronounced around Jupiter, the researchers say. Join our Space Forums to keep talking space on the latest missions, night sky and more!
0コメント