On August 5 , 2012 , the Mars Science Laboratory ( MSL ) mission successfully delivered the Curiosity rover to its intended target . It was the most complex and ambitious landing in the history of the red planet . A key component of the landing system , the requirements for which were driven by the mission ambitious science goals , was the Guidance , Navigation , and Control ( GN&C ) system . This paper will describe the technical challenges of the MSL GN&C system , the resulting architecture and design needed to meet those challenges , and the development process used for its implementation and testing .