Eight months and 352 million miles (567 million km) since it launched from Cape Canaveral, NASA’s Curiosity rover landed successfully in Gale Crater, marking the beginning of its 98-week mission to discover if Mars could have ever hosted life.
The landing, billed as ‘7 minutes of terror’, was NASA’s most ambitious to date. Upon entering the atmosphere, a 60-foot (18-metre) wide parachute slowed the rover from 13,200 mph (21,200 km/h) to 1,050 mph (1,700 km/h), before a ‘skycrane’ – a separate platform held up by rockets – ejected from the external shell, and lowered the rover to the surface on nylon tethers. The whole descent was automated, as the 14-minute radio delay between Earth and Mars made any last-minute adjustments impossible.
After undergoing tests to ensure everything is in good working order, Curiosity will leave the landing site and its mission will begin in earnest. Its eventual destination is Aeolis Mons, a mountain 6.5 km distant, composed of layers of sediment laid down when Mars had liquid water on its surface. These layers form a record of billions of years of geological history, allowing the rover to look for evidence of water and organic compounds – two conditions necessary for life as we know it.
To achieve this, Curiosity will use a combination of a high-resolution camera, to detect objects of interest at a distance, and a range of scientific equipment, to analyse the items found in more detail. It can determine the elemental composition of nearby rocks by vaporising a small amount with a laser, then analysing the light given off using a spectroscope. If the feature requires further analysis, instruments for X-ray diffraction, mass spectrometry and gas chromatography can determine the structure of samples collected with the rover’s mechanical arm.
Whether Curiosity discovers the building blocks of life or not, the next two years are sure to be tremendously valuable: the rover is the most advanced ever sent to Mars, and by measuring radiation levels and atmospheric conditions, it could pave the way for manned missions in the future.
IMAGE: NASA/JPL-Caltech/University of Arizona