Following the magnificent success of the complex sky crane system that delivered Curiosity to Mars in August 2012, and the rover's successes since then, NASA is working briskly on plans for another Curiosity-class Mars rover to visit the red planet, it is hoped, during the 2020 launch opportunity.
Functionally, the 2020 rover is a virtual clone of Curiosity . It will even utilize the backup nuclear power source from Curiosity (one of the few left in the U.S. inventory). This results in over a billion dollars in estimated cost savings by reducing development costs. Yet, despite this reliance on current technology, engineers will need to innovate many new designs for this mission to be successful.
First, there is the mission itself. Once the 2004 Mars Exploration Rovers (MERs) Spirit and Opportunity confirmed the evidence of a wet Mars in the distant past (tantalizing promises came from both from orbit and by Pathfinder in 1997), Curiosity's purpose was confirmed as an astrobiology mission. By this, NASA was not saying that it would search for life the way Viking did in the 1970s; rather, it would seek formerly habitable environments on and just under the Martian surface. The instruments carried onboard would be specifically accommodate that mission goal. From the ChemCam laser-firing spectrometer, to the SAM and Chemin onboard laboratories, to the Powder Acquisition Drill System, or PADS, drill, the entire rover was optimized for that task while still being capable of other research activities.
With voluminous results flowing in from Curiosity's nearly two Earth-years on Mars, the lessons learned can be applied to the 2020 rover and its mission design. This new machine will serve two primary duties. First, it will continue to refine data on once-habitable environments and test for biosignatures — chemical signs of past life. Second, it will identify rocks and soils that look promising — and for selected sites it is planned to take core samples, then store these samples for possible later pickup by a sample-return mission, as yet to be determined (and not yet funded).
Moving on to technological demands, it is this enhanced sample-gathering and caching capability that will be begging for innovation. The new rover will carry an updated drill and core-sampling mechanism, an evolved instrument package to identify and then analyze sample targets, and a caching mechanism in which up to 31 samples will be stored for eventual return to Earth by a subsequent lander, once (and if) approved.
Perhaps not since the Viking program of the 1970s has optimism run so high for a Mars mission. For Viking, anticipation centered on basic on-board tests of soil samples in an attempt to find Earth-like microorganisms. For the 2020 rover, the optimism is fueled by possible detection of past (and possibly present) life forms. The return of cached samples is a much larger challenge, involving a landing, cache retrieval, liftoff and rendezvous with a spacecraft equipped to return the samples to Earth. Never has such an involved, multi-step mission been attempted, and though sample-caching is part of the 2020 mission, a return trip is not. As the JPL team members like to say, "Mars is hard." ['Innovation the NASA Way' (US 2014): Book Excerpt ]