Cape Town - When US space agency Nasa lowers its latest planetary rover Curiosity – the size of small car – on to the surface of Mars, the operation will involve a complex combination of science, engineering and technology of such sophistication that even Jules Verne would have been hard-pressed to imagine it.
Curiosity, which weighs close to a ton, is scheduled to be deposited gently on a very precisely defined point on the surface of the so-called Red Planet at 8.31am SA time on Monday, ready to start work.
It will be the largest vehicle to land on another planet, and its size is allowing it to carry what scientists believe will be sufficient instrumentation to analyse samples of rocks, soil and atmosphere for them to be able to answer a big question: has there ever been microbial life on Mars and if so, what was it like?
Officially called the Mars Science Laboratory Project, the mission is being managed by Nasa’s Jet Propulsion Laboratory, a division of the California Institute of Technology at Pasadena, for the Nasa Science Mission Directorate in Washington.
Incredibly the rover will be lowered on three 7.5m nylon tethers from a massive “sky crane” that will have positioned itself above the planet’s surface using retro-rockets.
Even more incredibly, during what is being described by the space agency as “seven minutes of terror”, the spacecraft carrying the sky crane and its invaluable cargo will first have had to slow from a speed of close to 21 000km/h at the point of entry into the Martian atmosphere, 131km above the Gale crater landing area, to less than 2.5km/h.
“That kind of braking action for a one-ton payload demands the nail-bitingly precise unfolding of an intricately choreographed sequence of events. Key players: a red-hot heat shield, a huge parachute, 76 explosive bolts… and a Sky Crane,” writes Dauna Coulter of Nasa Science News.
And she quotes Jet Propulsion Laboratory’s Steve Sell, who is deputy operations lead for entry, descent and landing: “The whole ballgame transpires within seven minutes, from atmospheric entry to touch-down. The on-board computer calls the shots… if one manoeuvre fails, it’s game over.”
Perhaps mercifully, events during those crucial seven minutes will not be available live to controllers, because signals take 14 minutes to travel from Mars to Earth. So by the time mission control in California receives the signal that the space craft is about to enter Mars’s atmosphere, the actual landing will – hopefully – already have happened. - Cape Argus
l Visit http://www.nasa.gov/multimedia/videogallery/index.html?media_id=146903741; http://www.nasa.gov/msl; and http://mars.jpl.nasa.gov/msl/