NASA's Mars program could undergo major alternation, driven by budgetary and technical issues, as well as science goals.

"We've been getting inputs, advice, actions items...from the road mapping teams," said Doug McCuistion, Mars Exploration Program Director at NASA Headquarters in Washington, D.C. "Nothing is finalized at this point. There have been no final decisions made or, frankly, any interim decisions made as yet."

A scenario now under active discussion is slipping the mobile Mars Science Laboratory from 2009 to 2011 - a move that could see the building of two rovers to double-up the science that can be gleaned from the red planet, as well as reduce program risk.

NASA is engaged in an extensive campaign of "roadmaps" - a way to flesh out the details of a multi-year Mars effort that could lead to a humans-to-Mars effort by 2030, as listed on some NASA planning charts.

McCuistion said the potential to slip the Mars Science Laboratory (MSL) to 2011 is on the table, but it is not confirmed.

"The MSL discussions are swirling around a couple of things," McCuistion said. "One of them is robustness of the science and the technology."

Bigger than either of the now on-duty Mars Exploration Rovers - Spirit and Opportunity - the MSL is a "huge leap forward" from those smaller machines, McCuistion noted, being larger in mass and able to carry 10 times the payload mass.

Risky business: science eggs in one basket

Getting a much larger MSL safely down onto Mars means use of new technology, not air bags as utilized in the last three successful NASA Mars lander missions. "So there's technology risk trying to get to the surface of another planet," McCuistion added.

Another issue flagged by Mars road mapping officials regarding MSL is science risk. Plopping down in an uninteresting area of martian real estate is one concern. So too is the potential for a failure. Putting all the science eggs in one basket - in one large and costly lander - is risky business.

McCuistion said discussion is ongoing regarding doing more than one Mars Science Laboratory. "If we do two, we can't do two in 2009. There's no way," he explained, underscoring both technology and budget constraints.

"If one of the decisions is to go to two, and again, that decision has not been made, I can't do it in 2009," McCuistion said. "These guys [two MSL rovers] are expensive."

International partnership?

What role international collaboration might play in this time frame, "to keep the level of science up," is also being explored, McCuistion pointed out.

The potential for working with an international partner is possible, he said, depending on funding availability. Collaboration with an international capability, McCuistion deemed as "something that we all wanted to expand our international cooperation."

"The Europeans, as one example, are very anxious to get back to Mars after their trouble with Beagle," McCuistion said. The British-built Beagle lander was ejected by the now-orbiting European Space Agency Mars Express, but was lost to the planet in late December 2003.

Other potentials are "in the mill" for 2009 if MSL has to be moved, McCuistion stated.

Mars decision making and roadmap development are headed to NASA's Advanced Planning and Integration Office, to be tied together with other roadmaps underway, and then sent onward to the National Academies - committees of experts that review national issues and give advice to the federal government and the public.

Sample return trial run

In other Mars matters, a 2009 launch slot is targeted for NASA's Mars Telecommunications Orbiter (MTO). It is the first piece of communications infrastructure at the planet for all future Mars missions.

MTO will also carry a still to be picked science package, including an evaluation of laser optical communications gear to increase data flow between Mars and Earth. In addition, a key demonstration of tracking, rendezvous and maneuvering with an ejected football-sized canister is planned.

That experiment will not involve MTO capturing the canister. But the test will help hone future robotic Mars return sample procedures, McCuistion said.

A NASA-released announcement of opportunity (AO) focused on competitive selection of an MTO science package is forthcoming, McCuistion continued. That AO would only identify the dollar value and mass available for the science experiment.

"So there will be a science opportunity in 2009, which is very important for the science community to keep in mind," McCuistion said.

There is an overriding message from McCuistion regarding the major look at Mars exploration plans now in progress: "Science is still the driving priority. As soon as we have concrete information on what the mission portfolio looks like, we will be communicating that broadly and widely as soon as we are able to do that."

Budget issue: Spirit and Opportunity

An action item coming up shortly is the extension of the long-lived Spirit and Opportunity Mars Exploration Rover mission. A proposal is soon to land on McCuistion's desk to extend rover operations for another six months. But it's clear that money is tight.

"They are now funded through the end of March. I continually challenge them [the Mars Exploration Rover team] to try to reduce the cost of operations. But we are pretty close to the bottom of what it cost to operate these [two rovers]," McCuistion noted. "They are very labor-intensive from an operations perspective...they are an expensive system to operate. I think they will always be that way."

The money request that's forthcoming - with the price tag still to be determined - would give Spirit and Opportunity a new lease on life from April 1 to the end of September, McCuistion said.

Humans to Mars: safety checklist

Charts being floated about NASA point to a projected humans-to-Mars mission by 2030.

But to prepare for such a sojourn, a wide-ranging Mars human precursor checklist has been drawn up.

Deemed in some quarters as a "Safe on Mars" research agenda, there is a lengthy list of things to be done from a mission, technology, and science perspective before dispatching a crew to the red planet.

"It's amazing as you go through this," McCuistion concluded, "there are a lot of things that, as we dig deeper, a lot of us have not thought of. We need to do some very serious studies internally and externally to understand all the pieces...because it's a dangerous thing to be going that far away from home."