Porco also finds time for groundbreaking research, beginning in the 1980s with her work on the Voyager missions to Jupiter, Saturn, Uranus and Neptune. In fact, she’s considered one of the world’s foremost experts on the planetary rings and moons that circle these giant outer planets. Porco is now leading the imaging team on the Cassini mission, which is orbiting Saturn. Among her greatest discoveries so far are the giant geysers of icy particles (indicating the presence of water) on Saturn’s sixth-largest moon, Enceladus. Porco is also an imaging scientist on the New Horizons mission, presently en route to Pluto and the Kuiper Belt at the farthest edges of our solar system.