NASA's Low Density Supersonic Decelerator, or LDSD, is a saucer-like prototype -- the type of vehicle astronauts could eventually use on a mission to Mars. The space agency plans to test the craft on Thursday.
The saucer will be carried up to the stratosphere by a hot air balloon. Once at 120,000 feet, LDSD will be dropped. Four small rocket motors will then kick in, generating the saucer's signature spin. Once stabilized by the rotation, the craft will be launched toward space by its solid-fuel booster rockets.
Engineers expect the craft will reach a maximum speed of Mach 4 and top out at 180,000 feet -- the edge of the stratosphere. On its descent back to Earth, LDSD will test out two new braking systems. The first is a doughnut-shaped structure that inflates around the saucer and increases its surface area and atmospheric drag.
As the saucer slows further -- down to Mach 2.5 -- a supersonic parachute will deploy. If successful, it will be the largest parachute ever flown.
Less than forty-five minutes after LDSD takes to the air from the U.S. Navy's Pacific Missile Range Facility in Kauai, Hawaii, it will splash down in the Pacific Ocean.
"Regardless of the outcome, we know we will learn many important things about this technology," Michael Gazarik, NASA's associate administrator for space technology, said at a pre-launch press conference earlier this week.
Even if all goes as planned, the craft will need more fine tuning before it's Mars ready. Mars' atmosphere is much thinner than Earth's, so a spacecraft must displace more weight in order to soften its landing.
Two more test flights of the LDSD are planned for next year.