Free Astronomy Magazine

25 SMALL BODIES four giant planets. From the timings and depth of the secondary occultations attribu- table to the rings (symmetric with respect to the central event), the researchers were able to mark out with high accuracy that system. In summary, both rings are com- plete, rather dense and have well-defined edges. The inner ring has a radius of 391 km and the outer one of 405 km; the width is respectively of 6.6 km and 3.4 km, with a di- vision wide almost 9 km, inside which no material was detected. The mass of the first ring is comparable to that of a frozen object of about 1 kilometre in diameter, while the mass of the second is significantly smaller. The fact that all the secondary drops in flux are consistent with a system of homoge- neous rings throughout their length, makes