To achieve the precision needed for landing safely inside Gale Crater, the spacecraft will fly like a wing in the upper atmosphere instead of dropping like a rock. To land the 1-ton rover, an air-bag method used on previous Mars rovers will not work. Mission engineers at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, Calif., designed a “sky crane” method for the final several seconds of the flight. A backpack with retro-rockets controlling descent speed will lower the rover on three nylon cords just before touchdown.
During a critical period lasting only about seven minutes, the MSL spacecraft carrying Curiosity must decelerate from about 13,200 mph (about 5,900 meters per second) to allow the rover to land on the surface at about 1.7 mph (three-fourths of a meter per second). Curiosity is scheduled to land at approximately 1:31 a.m. EDT Aug. 6 (10:31 p.m. PDT Aug. 5).
“Those seven minutes are the most challenging part of this entire mission,” said Pete Theisinger, JPL’s MSL project manager. “For the landing to succeed, hundreds of events will need to go right, many with split-second timing and all controlled autonomously by the spacecraft. We’ve done all we can think of to succeed. We expect to get Curiosity safely onto the ground, but there is no guarantee. The risks are real.”
During the initial weeks after the actual landing, JPL mission controllers will put the rover through a series of checkouts and activities to characterize its performance on Mars while gradually ramping up scientific investigations. Curiosity then will begin investigating whether an area with a wet history inside Mars’ Gale Crater ever has offered an environment favorable for microbial life.
“Earlier missions have found that ancient Mars had wet environments,” said Michael Meyer, lead scientist for NASA’s Mars Program at NASA Headquarters. “Curiosity takes us the next logical step in understanding the potential for life on Mars.”
Curiosity will use tools on a robotic arm to deliver samples from Martian rocks and soils into laboratory instruments inside the rover that can reveal chemical and mineral composition. A laser instrument will use its beam to induce a spark on a target and read the spark’s spectrum of light to identify chemical elements in the target.
Other instruments on the car-sized rover will examine the surrounding environment from a distance or by direct touch with the arm. The rover will check for the basic chemical ingredients for life and for evidence about energy available for life. It also will assess factors that could be hazardous for life, such as the radiation environment.
“For its ambitious goals, this mission needs a great landing site and a big payload,” said Doug McCuistion, director of the Mars Exploration Program at NASA Headquarters. “During the descent through the atmosphere, the mission will rely on bold techniques enabling use of a smaller target area and a heavier robot on the ground than were possible for any previous Mars mission. Those techniques also advance us toward human-crew Mars missions, which will need even more precise targeting and heavier landers.” US space agency NASA says its state-of-the-art Mars probe will land on the planet on August 6th.Space experts at NASA announced the plan on Monday.
The space rover Curiosity is the largest Mars probe ever and was launched in November last year. It is in search of evidence of life on the Red Planet.The probe will move on wheels and, using various instruments such as a robot arm, sample rocks and sand from the surface of the planet. It can analyze samples on the spot.
Many scientists believe that Mars used to have a wet environment, an essential source of life. Some expect the probe to shed light on the origins of life.NASA experts say rocks in the area where Curiosity will spend two years investigating will likely contain water.Media Agencies
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