NASA

In an ongoing effort to restructure its Mars exploration program in the wake of deep budget cuts announced earlier this year, NASA announced plans Tuesday to send a new $1.5 billion rover to the red planet in 2020 based on the design of the agency's hugely successful Curiosity.

The as-yet-unnamed rover is the second new Mars mission announced in the wake of the budget cuts that will be built using already-existing designs, a money-saving architecture agency officials say is more in line with current funding reality.

"The challenge to restructure the Mars Exploration Program has turned from the seven minutes of terror for the Curiosity landing to the start of seven years of innovation," John Grunsfeld, NASA's science chief, said in a statement.

He was referring to Curiosity's innovative rocket-powered "sky crane" descent system that successfully lowered the nuclear-powered rover to the surface of Mars Aug. 6 after a nail-biting seven-minute plunge from space.

"This mission concept fits within the current and projected Mars exploration budget, builds on the exciting discoveries of Curiosity, and takes advantage of a favorable launch opportunity," Grunsfeld said after announcing the new mission at the American Geophysical Union's fall meeting in San Francisco.

In a briefing later Tuesday, Grunsfeld told reporters the availability of spare parts from Curiosity's development, including a backup nuclear generator, made the 2020 rover possible in the current budget environment. Equally, if not more important, he said, was the engineering expertise that got Curiosity to Mars.

"It's the availability of the spare parts but also the people and the engineering that went into building Curiosity that we still have," he said. "This whole team...is still together and we're going to leverage that to build on the Mars 2020 rover. That's what enables us to do the whole plan within the current budget."

The Obama administration's fiscal 2013 budget request called for a 20 percent reduction in NASA's planetary exploration budget with most of the cutbacks coming from the Mars program. Additional reductions are expected in later years.

As a result, NASA pulled out of two planned Mars missions that would have been conducted jointly with the European Space Agency in 2016 and 2018. At that time, no other "flagship" planetary missions like Curiosity's were in development.

Amid vocal criticism from some quarters of the scientific community, NASA began considering alternative approaches and mission scenarios.

In August, just two weeks after Curiosity's touchdown, NASA announced that it would launch a relatively low-cost Mars lander in 2016 that will make a rocket-powered descent to the surface to study whether the red planet's core is solid or liquid and whether the planet has tectonic plates that slowly move like Earth's continents.

Called InSight, for Interior Exploration Using Seismic Investigations, Geodesy and Heat Transport, the new spacecraft will be based on the design of NASA's successful Phoenix probe, a traditional solar-powered legged lander that touched down near the north polar cap of of the red planet in May 2008.

InSight will be equipped with a robotic arm, along with two black-and-white cameras and a geodetic instrument provided by the Jet Propulsion Laboratory in Pasadena, Calif., to measure the planet's rotation axis. As a so-called Discovery-class mission, the cost is capped at $425 million, excluding the price of the launcher.

The new rover announced Tuesday, along with the rocket needed to boost it to Mars, will cost somewhere in the neighborhood of $1.5 billion, plus or minus $200 million, according to a rough estimate by the Aerospace Corp.

The Curiosity rover, the centerpiece of the Mars Science Laboratory mission, cost some $2.5 billion over a decade of development. But the new rover will not require the same development of new systems and technologies, Grunsfeld said, which will make it easier for NASA to control costs.

Grunsfeld said the revised Mars program offers significant science that will keep NASA at the forefront of planetary exploration.

Along with its currently operational spacecraft and instruments -- the Curiosity and Opportunity rovers, two operational Mars orbiters and components aboard an ESA orbiter -- the agency's revised Mars program now includes:

The Mars Atmosphere and Volatile Evolution -- MAVEN -- orbiter, scheduled for launch in 2013

Communications gear for ESA's Trace Gas Explorer mission in 2016 and components for an astrobiology instrument in ESA's ExoMars rover mission in 2018

The InSight mission, scheduled for launch in 2016

The new rover, which will take off in 2020

"We've got lots of budget issues," Grunsfeld told reporters. "We're still in a continuing resolution for fiscal year '13, there are questions of sequestration. The administration is still considering our input to the FY '14 budget process.

"But all of these things that we've shown here fit within the president's budget request for fiscal year '13. ... I think it's a signal that folks really care, the administration, the Congress, the public, care about Mars exploration. So we're going to move forward on this pretty rapidly."

Rep. Adam Schiff (D-Calif.) endorsed the new rover mission, saying in a statement that "an upgraded rover with additional instrumentation and capabilities is a logical next step that builds upon now proven landing and surface operations systems."

But he wants NASA to move up the launch date to 2018.

"While a 2020 launch would be favorable due to the alignment of Earth and Mars, a launch in 2018 would be even more advantageous as it would allow for an even greater payload to be launched to Mars," he said. "I will be working with NASA, the White House and my colleagues in Congress to see whether advancing the launch date is possible and what it would entail."

Grunsfeld, however, cautioned that "2020 is ambitious, and a lot of it has to do with the science instrument development. ... It might be possible to do it in 2018, but it would be a push. What it might do is exclude certain science investigations that might be possible if we had the extra two years. That's something downstream."