Less than half the size of the Earth's moon, Saturn's satellite Iapetus is one of the few places in the solar system that offers a good view of Saturn's rings. This is because Iapetus' orbit is inclined almost 15 degrees to Saturn's equator. With the exception of Phoebe, none of Saturn's other satellites offer such a vantage point. Unlike haze-shrouded Titan, Iapetus has no atmosphere to speak of and is believed to be composed almost entirely of water ice.