The US space agency (Nasa) says it will launch a new rover to Mars in 2020.
The vehicle will be based on its Curiosity robot, which landed on the Red Planet in August.
Nasa expects to re-use many of the technologies that worked so successfully in getting the one-tonne spacecraft down into the huge equatorial bowl known as Gale Crater.
This included a rocket-powered crane that lowered Curiosity to the surface on nylon cords.
The announcement of a follow-up robot was made at the American Geophysical Union (AGU) Fall Meeting in San Francisco, the world's largest annual gathering for Earth and planetary scientists, and a major showcase for Nasa-led research.
It was communicated by the agency's science administrator, John Grunsfeld.
Hovering 'skycrane'
Nasa's budget for planetary science, and Mars research in particular, has been squeezed of late, forcing the Americans to pull back on their commitments to two European Red Planet ventures in 2016 and 2018.
But Mr Grunsfeld said there was scope in the financial outlook for a major mission at the end of the decade.
