“Space is often compared to our oceans. Throw a stone at the water and the density smothers its propulsion. Skim the stone across the surface and the propulsion is mostly preserved with minimal drag. This kind of approach could work for NASA's mission to Mars.” MarsNasaSpace TravelSpaceshipsDensityPropulsionNasa MarsSkipping StonesRed PlanetMission To Mars Author:Stewart Stafford