NASA has launched a $US2.5 billion rover towards Mars. Travelling at a speed of 10km per second, it is due to arrive there next August.
The Mars Science Laboratory was launched inside a capsule aboard an unmanned Atlas 5 rocket from Cape Canaveral Air Force Station in Florida at 10.02am (EST) on Saturday.
If it can land safely, the robot will then investigate Martian soils and rocks for any signs that current or past environments on the planet could have supported microbial life.
The Mars Science Laboratory is due to reach the Red Planet on the morning of 6 August 2012.
The BBC reports it is being aimed at a deep equatorial depression called Gale Crater, which contains a central mountain that 5km above the plain below.
The crater was chosen as the landing site because satellite imagery has suggested that surface conditions at some point in time may have been benign enough to sustain micro-organisms.
MSL is equipped with 10 sophisticated instruments to study the rocks, soils and atmosphere in Gale Crater.
The $US2.5 billion mission is funded for two years of operations, but the robot has a plutonium battery and should have enough power to keep rolling for more than a decade.