Curiosity, 10 years exploring Mars

NASA's car-sized Red Planet rover has set new standards in planetary exploration

This August marks 10 years since Curiosity, one of the most advanced planetary rovers ever launched, landed on Mars. For a decade the car-sized wheeled robot has been studying the climate and geology of Mars in preparation for human exploration and helping to answer questions about Mars's past suitability for life.

But its launch was repeatedly pushed back as NASA faced many delays. Finally, on 26 November 2011, the mission clock began as an Atlas V launched the rover from Cape Canaveral Air Force Station.

The selection of Curiosity's destination on Mars had begun in June 2006, when an international group started to whittle down 100 potential landing sites to just one. By June 2011 the 154km-diameter Gale Crater had finally been chosen for its exposed layers of sediments, thought to be left by the water of an ancient lake.

Curiosity's landing eventually came on 6 August 2012, and was aimed at the tightest landing ellipse of any mission to date. The Spirit and Opportunity rovers' landings had been within a predicted area of 150 x 20km in 2004; Curiosity was to narrow that down to just 7 x 20km. To achieve this, the craft had to slow down by a factor of around 10,000, from a relative approach velocity of 21,000km/h to a slow walking pace of just 0.75m/sec at touchdown - no easy feat for a rover 3m long by 2.8m wide, with a mass of almost 900kg. Curiosity's mission planners took a novel approach to landing, describing it as either 'the least crazy' solution or the 'seven minutes of terror'.

Feeling supersonic