Phoenix, the rover currently at the north pole of Mars, and Spirit and Opportunity, the two Energizer Bunnies of Mars' rovers, all carry science packages weighing, I believe, less than 20 pounds each. Flying to Mars soon will be the Mars Science Laboratory. Carrying about 143 pounds of science equipment, this rover will be the size of a small car! How do you gently place this payload on the martian surface? Well, boys and girls, with science, technology, engineering and mathematics saavy, of course. That and all the amazing folks at NASA and supporting contractors.
For an exciting .mov animation of its landing, go to mars.jpl.nasa.gov/msl/gallery/video/movies/MSLAnim1.mov
Last week, I was fortunate to tour the world's largest wind tunnel where tests were being conducted the main chute for the Science Laboratory. It's sixty feet in diameter when fully deployed, leaving ten feet of clearance on each side of this 80' x 100' wind tunnel. Look for the people walking in front of the wind tunnel intake in the photo outside the tunnel. Gives one a good perspective for the actual immensity of the tunnel.