The widest and most prominent gap in the rings of Saturn, about 4700 km wide, separating the A and B Rings, discovered in 1675 by G. D. Cassini. Its inner edge is 117 500 km from Saturn's centre. Images from the Voyager and Cassini probes show that it is not empty, but that several thin rings lie within it. The division could be accounted for by satellites 10–30 km in diameter clearing away ring particles, but no such satellites have been detected.
Subjects: Astronomy and Astrophysics.