Tiscareno, M. and Porco, C. (2001). "Cassini ISS Search for Inner Satellites of Jupiter." American Astronomical Society, DPS meeting #33, #37.09.


Abstract
During Cassini's approach to Jupiter, from 4 Oct 2000 to 6 Dec 2000, a series of narrow angle images was taken to search for any undiscovered satellites of Jupiter, focusing (to avoid scattered light from Jupiter) on the region from 2.6 RJ to 20 RJ, exterior to Amalthea but interior to Callisto. The spacecraft's distance to Jupiter for these images ranged from 82 million km to 25 million km, and the phase angle ranged from 20 degrees to 8 degrees. Due to limitations on observing time on the spacecraft, image sequences were taken at intervals ranging from many hours to days. The movement of the spacecraft, as well as the movement of any observed satellites, over these intervals would be so large as to make it impossible to identify objects by observing movement against a background of stars. Instead, a correlation technique was applied, which restricted the search to satellites with near-planar, near-circular orbits. These assumptions place additional limits on the orbital elements of any detectable satellite. At present, we are confident that no satellites exist in the search region with magnitudes (as seen from the spacecraft) brighter than 14.5, inclinations below 1.5 degrees, and eccentricities below 0.0002. This limit corresponds to an object with a diameter of 15 km, with an albedo of 0.1, at a range of 40 million km.