NASA says the Mars science rover Curiosity landed on the Martian surface on Monday morning to begin a two-year mission seeking evidence the Red Planet once hosted ingredients for life.
Mission controllers at the Jet Propulsion Laboratory near Los Angeles said they received signals relayed by a Martian orbiter confirming that the rover had landed inside a vast impact crater.
NASA says it has received the first two images from the Martian surface.
Curiosity is the most sophisticated mobile science lab ever sent to another world.
Facing deep cuts in its science budget and struggling to regain its footing after cancellation of the space shuttle programme - its centrepiece for 30 years - NASA had a lot riding on a successful landing. Mars is the chief component of its long-term deep-space exploration plans.
Curiosity is designed primarily to search for evidence that the planet most similar to Earth may have once harboured ingredients necessary for microbial life to evolve.