D ione ( "dy OH nee" ) is the twelfth of Saturn 's known satellites: orbit : 377,400 km from Saturn diameter : 1120 km mass : 1.05e21 kg I n Greek mythology Dione was the mother of Aphrodite (Venus) by Zeus (Jupiter). ... Both rotate synchronously and have dissimilar leading and trailing hemispheres. ... H elene orbits in Dione's leading Lagrange point. more images . ... H elene is in Dione's leading Lagrange point and hence was sometimes refered to as "Dione B". from LANL . ... Saturn .. ...