“Landing on Mars is an extremely challenging thing to do,” Ian Clark of NASA's Jet Propulsion Laboratory said at a press briefing from Kauai. “If you are going to cast your eyes on the prize of landing people on Mars, you’re going to need extremely large drag devices to slow those vehicles down.”
As The Christian Science Monitor reported earlier this month:
Clark is the principal investigator for NASA’s Low Density Supersonic Decelerator (LDSD) program, and he has led the development of two new devices to help ease large spacecrafts’ entry into Mars' atmosphere.
The first device is a six-meter (20-foot) inflatable doughnut known as the supersonic inflatable aerodynamic decelerator (SAID-R) that encircles the saucer-shaped craft. Once deployed, SAID increases the diameter of the craft and creates enough drag – theoretically – to slow the vehicle from Mach 3.8 to Mach 2.7.
The second device, a supersonic parachute, made of Kevlar covered in a special coating designed to withstand temperatures up to 600 degrees Fahrenheit, slows the craft even further.
Testing the new technologies presents enormous logistical challenges. For instance, engineers must manage to get the craft to the upper stratosphere, where conditions are akin to those of the Martian atmosphere. That's four times higher than a plane would fly, LDSD project manager Mark Adler said at the briefing.
The attempt off the coast of the Hawaiian island of Kauai Saturday will test the disc-shaped vehicle and a giant parachute.
Since the 1970s, NASA has used the same parachute design to slow landers and rovers as they streak through the thin Martian atmosphere. With plans to send heavier spacecraft and eventually astronauts, the space agency needs a much stronger parachute.
NASA is testing the technology high in Earth's atmosphere because conditions there are similar to that of Mars.
High winds at the Kauai military range forced NASA to miss its original two-week launch window in June.