Scientists developed a theory indicating that Saturn's system of moons began with a family of different relatively huge moons, such as Jupiter's Galilean satellites. Researchers believe that moon mergers made Saturn's larger moon, Titan, which eventually shed sufficient material to develop smaller moons including Dione and Rhea. "We think that the giant planets got their satellites kind of like the sun got its planets, growing like miniature solar systems and ending with a stage of final collisions," said lead author Erik Asphaug from the University of California in Santa Cruz.