The 5 most amazing things we've learned from NASA's Cassini mission

After 20 years, thousands of gorgeous photos, and a whole lot of science, the Cassini spacecraft is finally ready to retire. But there'll be no relaxing days on the beach for this old spacecraft; instead, it will go out in a blaze of glory. More specifically, NASA's planning to crash it into Saturn's atmosphere, where it will melt and vaporize.