NASA's white knuckled ride with a Mars rover Seven minutes of
terror. It sounds like a Hollywood thriller, but the phrase
describes the anxiety NASA is expecting as its car-sized robotic
rover tries a tricky landing on Mars late on Sunday. Skimming
the top of the Martian atmosphere at 21,000km/h, the Curiosity
rover needs to brake to a stop - in seven minutes. The rover is
headed for a two-year mission to study whether Mars ever had the
elements needed for microbial life. Because of its heft, the
900-kilogram robot can't land the way previous spacecraft did.
This artist's concept depicts the moment that NASA's Curiosity
rover touches down onto the Martian surface. Photo: NASA They
relied on airbags to cushion a bouncy touchdown. This time NASA
is testing a brand new landing that involves gingerly setting
down the rover similar to the way heavy-lift helicopters lower
huge loads at the end of a cable. How hard is it? "The degree of
difficulty is above a 10," says Adam Steltzner, an engineer at
NASA's Jet Propul