Before NASA decided to help SpaceX on its journey to Mars, details of which company chief Elon Musk plans to unveil on Tuesday, the U.S. space agency reviewed the plan for SpaceX's first mission, slated to launch in 2018, and decided it has a reasonably good chance of success.
For NASA, a successful mission means that SpaceX's Mars vehicle, called Red Dragon, flies through the Martian atmosphere with its thrusters firing in the direction of travel, a technology known as supersonic retrograde propulsion. The feather in the cap would be a propulsive landing on the Martian surface.
"This is a critical, critical technology for us," said Phil McAlister, director of NASA's Commercial Spaceflight Division. "This is flight data that would not be available to us by any other means."
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NASA is working toward sending astronauts to Mars in the mid-2030s. Musk aims to beat that by a decade.
The tech entrepreneur, who also heads Tesla Motors, is scheduled to unveil details of his Mars initiative during a presentation on Tuesday at the International Astronautical Congress in Guadalajara, Mexico.
SpaceX's debut mission is well into the planning stages. The company hopes to launch an unmanned Dragon capsule aboard a heavy-lift Falcon rocket in 2018, the next time the orbits of Earth and Mars are favorably aligned for flight.
After traveling for about 180 days, Red Dragon would enter Mars' thin atmosphere and make a powered descent and landing on the surface.
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Dragon is too small to have passengers aboard, but it would become the biggest spacecraft ever to land on Mars.
NASA wants to be able to land 20- to 30 tons on Mars at a time. So far, the heaviest payload to land was the one-ton Curiosity rover.
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