Dr. John Grunsfeld, former astronaut and Deputy Director, Space Telescope Science Institute (STScI), Baltimore speaks at the presentation of the permanent exhibit of the James Webb Space Telescope at the Maryland Science Center on Wednesday, Oct. 26, 2011 in Baltimore. Photo Credit: (NASA/Carla Cioffi)

SAN FRANCISCO — Just four months after the successful landing of the Mars Science Laboratory mission’s Curiosity rover, NASA announced plans to send another science rover to the red planet in 2020.

Faced with budget constraints that are likely to make it difficult for NASA to launch ambitious planetary missions to Jupiter’s moons or other enticing destinations in the near future, NASA officials have been evaluating the type of science and exploration missions the space agency could conduct with available resources, NASA’s associate administrator for science, John Grunsfeld, said Dec. 4 at the American Geophysical Union (AGU) meeting here. Those resources, including spare parts, engineering and technical expertise developed during a decade of preparation for the Curiosity mission, led NASA officials to conclude that a new Mars rover would provide important scientific contributions while fitting within the current budget, Grunsfeld said.

The new Mars rover including its launch is expected to cost roughly $1.5 billion, according to a study conducted for the Mars Program Planning Group by the Aerospace Corp., the federally funded research and development center in El Segundo, Calif. NASA officials, pondering the timing of the new Mars mission, considered launching it in 2018, but decided to push the mission back two years given limited funding and concerns about the time needed to develop a new suite of advanced scientific instruments. Development problems with three primary instruments led to a two-year delay in Curiosity’s launch, which originally was scheduled for 2009.

By waiting until 2020 to conduct the new Mars mission, NASA also frees up enough funding to play a limited role in the European Space Agency (ESA) ExoMars program, which features plans for a communications relay satellite with a NASA-provided antenna and an entry, descent and landing module in 2016, followed by the 2018 launch of an ESA-built rover. NASA initially planned to play a major role in the ExoMars missions, sharing the cost of the rover and providing Atlas 5 rockets for both the 2016 and 2018 launches.

Early this year, however, NASA withdrew as a major partner in the ExoMars program, citing funding problems. Russia stepped into the breach, agreeing to provide Proton launches for the two missions, an instrument for the telecommunications orbiter, an experiment for the rover and to take principal responsibility for the entry, descent and landing demonstration.

NASA, the world’s expert on planetary entry, descent and landing, now plans to support the demo and provide the Electra telecommunications package for the 2016 orbiter.

NASA also plans to work with ESA on the Mars Organic Molecular Analyzer, an ExoMars rover instrument designed to identify organic matter in martian rocks and soil. NASA has pledged to work with ESA on the Mars Organic Molecular Analyzer through completion of the flight-qualified instrument, Grunsfeld said.

Immediately following the AGU conference, NASA planned to establish a team to define scientific goals for the 2020 Mars rover mission. Then, space agency officials will begin soliciting instrument proposals in June or July 2013, Grunsfeld said.

Sample caching?

The science community is likely to conduct a lively discussion on the types of instruments the rover should carry. Within minutes of the announcement of the mission, scientists began discussing whether the new rover should be designed to collect the most important soil and rock samples for return to Earth during a later mission.

Steve Squyres, a Cornell University astronomy professor and principal investigator for NASA’s Mars Exploration Rover mission, said in an interview that the process, known as caching, was the primary recommendation of the National Research Council’s planetary science decadal survey panel, which he chaired. The panel’s report, “Visions and Voyages for Planetary Science in the Decade 2013-2022,” published in March 2011, called on NASA and ESA to join forces on a three-mission Mars sample return campaign. The rover mission described by Grunsfeld is “absolutely capable” of performing the type of caching the panel recommended for the first leg of that campaign, the Mars Exobiology Explorer-Cacher, Squyres said.

The Mars rover science team will explore the question of caching as it determines the best possible combination of instruments given the vehicle’s mass and power constraints. “The decadal survey said the highest priority is caching for some future unspecified sample return,” Grunsfeld said. The science team “may decide to do that. They may decide they want to do in-situ science including sample acquisition and characterization.”

As the space agency defines the next rover mission, it also plans to continue supporting NASA’s current Mars missions, including the Mars Reconnaissance Orbiter and the Curiosity and Opportunity rovers, “to make sure we can operate those missions as long as they are viable,” Grunsfeld said. NASA also plans to launch the Mars Atmosphere and Volatile Evolution mission in late 2013 and a Discovery-class mission called InSight in 2016 designed to study the rocky planet’s deep interior.

During 2013, NASA’s Jet Propulsion Laboratory, which developed and built the Curiosity rover, will begin taking stock of spare parts that could be used in a new rover and identifying obsolete parts. One important spare already discussed is Curiosity’s backup radioisotope power system, the Multi-Mission Radioisotope Thermoelectric Generator. “We have a flight spare and an engineering test unit that we will try to upgrade to a backup,” Grunsfeld said.

In addition, NASA still has access to the engineering team that accomplished one of the most challenging missions in the space agency’s history when the car-size rover equipped with a complex instrument suite was lowered to the martian surface by a hovering sky crane. Grunsfeld, who was in the control room when the rover slowly touched down near Gale Crater, said the first expression he saw on the faces of program officials gathered was “disbelief that it all worked.” That expression was quickly replaced by celebration and backslapping, he added.

Debra Werner is a correspondent for SpaceNews based in San Francisco. Debra earned a bachelor’s degree in communications from the University of California, Berkeley, and a master’s degree in Journalism from Northwestern University. She is...