spacetoday.net: Astronomers discover 11 moons of Jupiter

Posted: Fri, May 17, 2002, 7:59 AM ET (1159 GMT)
Jupiter (NASA)

Astronomers announced Thursday that they had discovered 11 moons orbiting Jupiter, giving the giant planet a total of 39 natural satellites, more than any other planet. The moons were discovered in images taken in mid-December by a wide-field CCD camera at the Canada-France-Hawaii Telescope on Mauna Kea, Hawaii. All 11 moons are small bodies, between two and four kilometers across, orbiting Jupiter in elliptical, inclined, retrograde orbits at an average distance from Jupiter of 21 million kilometers. The orbits suggest these are captured bodies from the asteroid belt, but since capture is an inefficient mechanism in the present-day solar system, astronomers think that the bodies were captured in the early history of the solar system. Further research may allow planetary scientists to differentiate between two models for the capture of these bodies. Astronomers believe that Jupiter may have up to 100 moons one kilometer or larger in diameter.