AIN Blog: Curiosity, a Shot in the Arm for NASA
In this year of the summer Olympics, it is only fitting that NASA scored a gold medal when it “stuck the landing” on its Curiosity rover, the most ambitious lander ever sent to another planet. In the wee hours of Monday morning, space geeks (most wear that label proudly) celebrated the news that Curiosity had survived the so-called “seven minutes of terror.” Information sent to and from Curiosity when it arrived at the Red Planet took seven minutes to travel the same 354 million miles that the craft had spent more than eight months traversing, so Curiosity was left to accomplish the touchdown on its own. By the time its NASA handlers could have identified and reacted to any possible hiccups during the descent, Curiosity would already have joined the ranks of failed missions. Sixty percent of exploration missions to the planet have failed to complete their objectives, and if Curiosity’s automatic landing had not worked perfectly, Mars would have gained a new crater.
Because the craft has outgrown the airbag-clad “bounce like a beachball until stopping” delivery approach of previous smaller missions, NASA’s engineers were forced to think outside the box for the bulky Curiosity and develop a new method to deliver the Ford Pinto-sized robot to the surface survivably. The $2.5 billion spacecraft would have to slow from 13,000 miles to zero using a system that had never been operationally tested until the mission itself. It simply had to work right the first time, and it did.
From its entry into the Martian atmosphere, until it touched down firmly, the craft had no fewer than six configurations. The lander’s streak through the thin atmosphere was blunted by a heat shield that slowed the initial descent to approximately 900 mph—enough to deploy a supersonic parachute, images of which were captured in a fly-by overhead photo by the Mars Reconnaissance Orbiter (keeping with the Olympic theme, NASA earned extra style points for that). Once the speed slowed to 190 mph, a “rocket backpack” landing stage attached to the rover fired and eventually brought the craft into a hover above the surface. The backpack then unspooled cords, lowering Curiosity to the ground like the claw reaching for a stuffed animal in an arcade game, protecting its delicate instruments from the dust storm that the retro-rockets closer to the surface would have kicked up. Once the rover was safe, it cut the cords connecting it to the flight stage, now useless, which flew off several thousand feet and crashed in a planned maneuver out of harm’s way. As an added bonus, the thrust from the rockets blew away the thick dust in several patches near the lander, unveiling bedrock for Curiosity to study and sample eventually.
Since touchdown we have been treated to many new pictures of the Martian landscape as Curiosity slowly awakens, stretches its limbs and reports system checks back to the Jet Propulsion Laboratory. Image manipulators have been having a field day with purported “first images” on the Internet showing the beast from Aliens and, even more apropos, Marvin the Martian peeking into the camera’s field of view. In a high-resolution panorama just released, the Martian surface looks a bit like Arizona, minus the cacti, an observation sure to get the conspiracy theorists whispering.
The path to Mars has rarely been smooth or carefree. Pinned to a bulletin board in my office is a pack of Hot Wheels toys—a souvenir from a story assignment long ago—containing miniature replicas of the Mars Climate Orbiter (MCO) and Mars Polar Lander (MPL). Both 1998 missions managed to reach the planet but were lost before they could accumulate any data. MCO miscalculated its orbit due to a programming glitch and burned up when it accidentally entered the atmosphere, while MPL suffered a suspected landing thruster shutdown and supposedly dashed itself against the Martian surface. The underlying cause of both failures was eventually attributed to engineers trying to accomplish too much with limited funding.
Curiosity, the third-generation rover to land on the fourth planet from the sun following Sojourner in 1997 and the twins Spirit and Opportunity (the latter is still functioning, 30 times past its design lifespan) in 2004, is about to embark on a two-year mission that will eventually find it climbing a mountain searching not for life itself, but for clues of whether our planetary neighbor could have ever sustained life as we know it. At a time when NASA as been eviscerated by budget cuts and loss of prestige from the retirement of its long serving space shuttle fleet, the unorthodox but successful landing on Mars by its most capable scientific rover yet was just the ticket for the agency to show it still has that same can-do attitude, as well as the same know-how, that put men on the moon less than 70 years after the first powered flight.