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Aussie dish key to Mars landing
When NASA's new Mars rover, Curiosity, makes its precarious descent to the planet's surface, Australia will provide a communications link vital to the mission's success.
Later today three antennae at NASA's deep space tracking station near Canberra will tilt towards Mars and make contact with the planetary rover, Curiosity, as it prepares to descend onto the Martian surface.
More than 40 years since Australia relayed man's first steps on the moon to the world, we will play a crucial role in NASA's latest space mission by communicating directly with the space probe as it makes its final approach. ''We're the only country in the globe that is going to be doing that,'' said the director of the Canberra Deep Space Communication Complex, Ed Kruzins.
The position of Earth to Mars puts Australia in a unique position to send and receive signals from the rover. The Parkes radio telescope in New South Wales and another antenna near Perth will provide back-up.
If all goes as planned, and that is far from guaranteed, the 900 kilogram rover, which has been cruising inside a spacecraft towards Mars since its launch in November, will touch down at 3.31pm AEST.
''I think the best way to describe the mission is audacious, but we're very confident of this working out,'' Dr Kruzins said. Fitted with the most advanced set of instruments ever sent to study the Red Planet, the rover's task during its two-year mission will be to determine whether Mars is, or ever was, habitable.
But before any Martian discoveries can be made, the rover must make its highly complex descent, which begins when the spacecraft enters the planet's atmosphere and requires a sequence of precise technical manoeuvres. The time delay between the two planets means the rover must land itself, an event NASA scientists call the ''seven minutes of terror''.
As the spacecraft slows from the friction of the planet's thin air, a 16-metre parachute will eject to further slow the ship before its heat shield separates and a sky crane device prepares to lower the rover into Gale Crater, a 150-metre wide depression named after the amateur Australian astronomer Walter Gale. During the final part of the descent the craft will lose contact with Earth and so send signals via the Mars Odyssey orbiter, which will hover above the landing site.
NASA's associate administrator in charge of the science mission directorate and the $US2.5 billion program, John Grunsfeld, said last month Curiosity's landing would be the ''hardest NASA mission ever attempted in the history of robotic planetary exploration''.
The spacecraft will communicate with the Canberra tracking station, which is managed by the CSIRO, through a series of tones, which signify various steps in the landing process have been activated. ''We'll be carrying the signals as it passes through the atmosphere, descends on its parachutes, fires its thrusters and lands on the surface,'' said Dr Kruzins.