NASA built a flying saucer, which they’ve called the Low-Density Supersonic Decelerator, that will eventually land large payloads on other planets. via Extreme Tech:
No, humble inhabitants of Hawaii, the US government hasn’t increased the level of psychoactive drugs in your water supply: That really is a flying saucer that just flew past your window at three times the speed of sound. Dubbed the Low-Density Supersonic Decelerator, NASA is hoping that this flying saucer is the secret to eventually landing larger payloads on other planets — such as sending a human exploration party to Mars, along with plenty of supplies. The LDSD is on a pretty aggressive schedule, with seven major tech demos over the next 24 months, and could be used in a real mission to Mars in 2018.
Later this year, NASA’s Jet Propulsion Laboratory will use a balloon to launch a test vehicle up to an altitude of 120,000 feet (36.5 kilometers) above Hawaii. The test vehicle will then use a rocket to reach supersonic speeds and raise its altitude yet further to 180,000 feet (54.8 kilometers)… and then it will cut its engine and begin to free fall back to earth. As the capsule passes Mach 3.5 (2,600 mph), the LDSD will kick into action, sprouting a Supersonic Inflatable Aerodynamic Decelerator (SIAD) from the craft and filling it with pressurized air. With the SIAD fully inflated, the spacecraft looks awfully like a flying saucer. The SIAD slows the craft down to around Mach 2, whereupon a massive 30-meter-diameter parachute will then be used to bring speeds down to subsonic landing speeds.