Unless you happen to be a roving robot with serious NASA connections, you probably won't be visiting Mars anytime soon. While no doubt a bummer to aspiring astronauts, there are ways to look for little green men without leaving the Earth's atmosphere. Journey to Mars, a kid-friendly site from San Francisco's Exploratorium, puts visitors close enough to the red planet that they'll likely accept their Earth-bound fate with good cheer. Visitors can start their adventure with an informative and fun look at how the "robotic scientists" do their job -- it's not easy being an explorer, chemist, geologist, meteorologist, and photographer. Of course, the photos and video section is required viewing. Spot any signs of life?