Earlier this week, we highlighted Snagfilms.com in our collection "20 Places to Watch Free Movies Online." When you dig into their collection, you will find some well known, recent films, including Morgan Spurlock's Super Size Me and Naomi Wolf's The End of America. And then you can also stumble upon some worthwhile educational documentaries. Above, we feature "Asteroids: Deadly Impact," a National Geographic documentary that asks whether the Earth could experience another cosmic collision with an asteroid (as happened 65 million years ago), what the aftermath might look like, and whether can we do anything to prevent it. You can find more documentaries along these lines in SnagFilms' Science and Nature Channel.