![]() Five were found before 2000, and only eight more have been discovered since then.īesides the interest in their origins, these prograde moons could make suitable targets for a flyby from an upcoming mission. “The reason is that they are closer to Jupiter and the scattered light from the planet is tremendous,” he says. They’re harder to find than the more distant retrograde moons, though, says Sheppard. Three of the newly discovered moons are in among 13 others that orbit in a prograde direction and lie between the large, close-in Galilean moons and the far-out retrograde moons. Only five of all the retrograde moons are larger than 8 kilometers (5 miles) Sheppard says the smaller moons probably formed when collisions fragmented larger objects. Jupiter probably captured these moons, as evidenced by their retrograde orbits, opposite in direction to the inner moons. Nine of the 12 are among the 71 outermost Jovian moons, whose orbits are more than 550 days. New MoonsĪll of the newly discovered moons are small and far out, taking more than 250 days to orbit Jupiter. If we could count all moons measuring at least 3 kilometers across, “Saturn would have more moons than all the rest of the solar system,” says Brett Gladman (University of British Columbia, Canada), who helped identify the new Saturnian objects but was not involved in the Jovian observations. (The fragments have not been tracked carefully enough to count as moons yet, though.) The more numerous Saturnian objects might have come from a collision that disrupted a larger moon a few hundred million years ago. A search for objects with sizes down to about 3 kilometers across that are moving along with the gas giants found three times more near Saturn than near Jupiter. However, while Jupiter may have the most moons for now, Saturn might catch up. The new finds put Jupiter’s lunar family count well ahead of Saturn’s 83 confirmed moons. (Note: The number of moons in this diagram is not up to date.) This top-down diagram shows the orbits of moons around Jupiter: Purple denotes the Galilean moons, yellow for Themisto, blue for the Himalia group, cyan and green for Carpo and Valetudo, respectively, and red for far-out retrograde moons. Other data from Sheppard’s observations even enabled recovery of the last “missing” Jovian moon, S/2003 J 10 the newest observations extended the track of its orbit to 18 years. The MPC's orbital calculations confirm the new objects are in orbit around Jupiter. The discoveries bring the list of Jovian moons to 92, a hefty 15% increase from the previous tally of 80. More publications are expected, says Scott Sheppard (Carnegie Institution for Science), who recently submitted observations of the Jovian system taken between 20. ![]() Since December 20th, the Minor Planet Center (MPC) has published orbits for 12 previously unreported moons of Jupiter. ![]() The biggest planet in the solar system now has the largest family of moons. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |