The Martian' just scratches surface of danger on Mars

Martians are not the villains. Mars is. At least, that's the message in the new big-screen space thriller "The Martian."

After an astronaut is stranded alone at a Martian research base, the planet does its best to starve, suffocate, and freeze the puny human. Yet the perils in the movie are just a taste of the challenges that Mars will throw at hu