简介：<p>　　The Cassini spacecraft was sent on its way to Saturn in 1997. Since then, she has travelled nearly four billion kilometers, delivered a probe to a toxic moon, discovered phantasmagorical structures on the planet&#39;s icy rings, studied the startling atmosphere on a tiny moon. Now, on a daring spiral orbit, Cassini will streak toward Saturn itself, streaming data to Earth before being torn apart.</p>…