 The discovery of Saturn's "Phoebe ring" in 2009 further strengthened the probability that this process first described by Soter plays a significant role in shaping Iapetus's appearance.In 1977-1979, Soter co-wrote, along with Carl Sagan and Ann Druyan, Carl Sagan's monumental 1980 astronomy documentary series "".Since then, he has also acted as advisor on a number of science documentaries, such as the IMAX films "Blue Planet" and "Cosmic Voyage".