Washington - NASA's Mars rover Curiosity, loaded with the most-sophisticated instruments ever used to explore another world, touched down on the Red Planet early Monday morning, on a quest for signs of whether the Red Planet has evidence of past and present habitable environments.
"Curiosity rover has landed on Mars ... The time of day at the landing site is mid-afternoon -- about 3 pm local Mars time at Gale Crate," NASA announced.
Curiosity landed near the base of a layered mountain three miles (five kilometres) high inside the Gale Crater on Mars. The crater spans almost 100 miles -- an area as large as Connecticut and Rhode Island combined.
Planetary geologists are intrigued because data from the US Mars Reconnaissance Orbiter suggest the low-lying crater floor once was wet with water. Scientists also think the site might be rife with "organics" -- carbonaceous compounds that are key chemical building blocks for life.
Traditional Mars space-trucks including Sojourner, Spirit and Opportunity were dropped onto a lovely air-bag to cushion their fall, the de facto landing experience for a rover. But Curiosity is huge -- the size of a mini cooper -- so air bags are not its thing. Instead, the rover was lowered onto the Martian surface by a "sky crane".
NASA has dubbed that fall from space "Seven Minutes of Terror" in a video describing the onrushing event.
At nearly a ton, the six-wheeled vehicle dwarfs all previous robots sent to the surface of the planet. It is about twice as long and more than five times as heavy as any previous Mars rover.
During a prime mission lasting one Martian year -- nearly two Earth years -- researchers will use the rover's tools to study whether the landing region has had environmental conditions favourable for supporting microbial life and favourable for preserving clues about whether life existed.
The $2.5 billion Mars Science Laboratory, the formal name of the mission deploying the Curiosity rover, was launched from Cape Canaveral in Florida on 26 November 2011.
