The Mars Global Surveyor has beamed back exciting pictures for scientists to ponder for years to come, but it did not arrive at the Red Planet unscathed. Engineers at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., had to redesign the craft’s approach to Mars soon after launch from Cape Canaveral Air Force Station in November, 1996. One of the two 18-foot-long solar panels had snapped open like a screen door in a gale. The other panel unfolded smoothly.