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What happened to Mars?

The University of Colorado is studying whether changes in the Red Planet's atmosphere affected its ability to support life.

A rendering of the MAVEN spacecraft that is being conceived of by a team led by University of Colorado professor Bruce Jakosky. The project aims to study the atmosphere of Mars in order to determine why it changed over the last four billion years, and whether the planet previously was suitable for life. Lockheed Martin

BOULDER, Colo.--As anyone who spent a lot of Saturday mornings watching cartoons knows, Martians are for real, and they're green. But for scientists, things aren't quite as certain. So now, a group is setting out to find out whether the Red Planet could in fact have supported life.

In September, NASA awarded the University of Colorado the biggest research grant in the school's history for a project led by professor Bruce Jakosky to investigate the history of the climate on Mars. The idea behind the $486 million project--known as Mars Atmosphere and Volatile Evolution mission, or MAVEN--is to try to discover why Mars' climate has changed over the past few billions years, and whether the planet before those changes was an environment suitable for life.

I visited Jakosky in his office at the University's Laboratory for Atmospheric and Space Physics (LASP) building on Wednesday as part of Road Trip 2009, my annual search for the best stories the country has to offer. And while there, Jakosky explained the rationale for a project that, if successful, could occupy scientists for decades.

Set to launch in November 2013, MAVEN (see video below) is now in what Jakosky said is phase B of a five-phase development cycle. Phase A is concept development; phase B is about determining requirements and preliminary design; phase C is final design and early building; phase D is assembly, testing, and launch operations; and phase E is the science mission.

If the MAVEN team--which is made up of a group from LASP, as well as partners at NASA's Goddard Space Flight Center, the University of California at Berkeley and Lockheed Martin--passes the major review that comes at the end of phase B, it will move on with its goal of attempting to figure out what led to what Jakosky said are dramatic changes in Mars' atmosphere that have been previously detected by other missions to the fourth rock from the sun.

The highest-level goals for MAVEN are to learn as much as possible about Mars' geology, its interior, its original potential for life and if there was ever life there.

Jakosky explained that past research has demonstrated that Mars used to have a much thicker atmosphere than it does today, and that there likely was water on the planet's surface. Those together indicate an environment that would have been conducive to life. But what is not known is the relationship between the atmosphere, as it has changed, and the potential for supporting living things.

One theory of the MAVEN project is that the disappearance of Mars' magnetic field may have led to the loss of its atmosphere. NASA

The evidence, he said, is that Mars' atmosphere has tremendous amounts of gas to space. The question, however, is what gases, and how much. "So what we'd like to do is observe the escape of gases over (the last) 4 billion years," Jakosky said.

Clearly, there's no way to hit rewind and see precisely what gases there were, and how they escaped. But Jakosky said that by looking at the Martian atmosphere today, and seeing the rate of gas escape today, and why that's happening, the MAVEN scientists can extrapolate back in time, potentially letting them learn what happened over 4 billion years. "We don't know what Mars has done," he said, "but we know what the Sun has done."

And so one of the biggest goals of the project is to measure the ratio of isotopes in the Martian atmosphere, he said, and to see what the loss of hydrogen, oxygen, carbon and nitrogen has been. "Those will tell us about the total loss over time," Jakosky explained.

Eight instruments
The MAVEN project will be comprised of eight major instruments on board the spacecraft to measure the key properties and processes going on today, and it will be the first time such a suite of instruments will have been deployed to Mars.

"It's really a mission of discovery," he said. "We're exploring the upper atmosphere (of Mars) for the first time."

Goddard will produce two of the instruments; LASP two; and UC Berkeley four. The spacecraft will be made by Lockheed Martin in South Denver, Colo.

But while this particular group of instruments will never have been deployed before, the mission itself is "high heritage," Jakosky said, meaning that most of its profile has been done before, in earlier missions. "All we're doing is adding it all together."

Indeed, he said, NASA awarded the MAVEN project, and the nearly half-billion dollars in funding, to Jakosky and his team because their proposal was deemed to have the lowest risk. That was due to the experience everyone on the project had, and because the instruments in question had been deployed on similar projects in the past, he said.

Still, much about how the project is unknown, as is always the case in large-scale initiatives like this, Jakosky said. What is known, however, is that the MAVEN team has a strict top spending limit of $486 million.

But he added that in order to get to the point of having been selected to run the MAVEN project, his and other teams competing for the honor probably spent $60 million or more preparing for the selection process. And that means that his group is battle-tested and ready to move forward, he suggested.

In competitive environments, he explained, teams have to work very hard to make sure every T is crossed and I is dotted. "I see through our mission the benefits of having done that," he said. "We put together the best mission (proposal) we could. Now, we have to implement the full technical capabilities on schedule and on budget."

I asked Jakosky, as the recipient of such a big grant--around $200 million will go to the University of Colorado alone--if he feels that there's much pressure to deliver the goods.

"There is, but I've got such a good team...that I feel very confident," he said. "We've been given (nearly) half a billion dollars of the public's money. So we have to provide the mission and the science back to them. That's a heavy responsibility."

What happened to Mars?
Based on evidence gathered from previous Mars missions, scientists feel confident that the planet once had standing water on the surface. That's because of channels indicating rivers and closed depressions that could have been lakes. But today's Martian atmosphere wouldn't support water on the surface, for a number of reasons, not the least of which is that it would freeze. So why the change?

Jakosky said that the MAVEN team is exploring the interaction between Mars and the Sun. One question is what role solar winds had in stripping off Mars' atmosphere.

One might conclude that the atmosphere decayed over billions of years, but Jakosky said that the question there is why that happened. Mars is too heavy for molecules from its atmosphere to have simply escaped into outer space, so one of the most important questions MAVEN will seek to find the answer to is what gave those molecules the energy to leave. And based on what they know, solar winds and UV light from the Sun are suspected as two major culprits.

Assuming that MAVEN passes its phase B review, and makes it all the way to launch, the project would have the go-ahead for one year of Martian atmospheric exploration. Much of the analysis of the data would be done in real time as it comes back from the spacecraft, but Jakosky said that based on the results of prior missions like Pioneer Venus, he would expect that scientists would spend 30 years or more analyzing the MAVEN data.

Of course, he hopes that the MAVEN project is such a success that NASA gives the go-ahead for an extension of the mission, likely to a full Martian year, which is just less than two Earth years.

But the first task, he said, is to worry about the work that must get his team from now until launch. And he knows that the path to success is hardly assured. Fully one-third of the nine Mars missions NASA has undertaken have failed, he said. "There are a thousand opportunities to fail between now and a successful mission. Our job is to make sure we don't fall into them, and (to) succeed."

For Jakosky, MAVEN is a chance to add a big exclamation point to his career, particularly because he hasn't been the leader of a mission before. "This is the capstone of my career," he said. "I think this is important enough that I'm willing to spend ten years out of my career doing this mission."

And why should the public be satisfied that the MAVEN team is spending almost a half billion of their dollars?

"We're exploring the solar system (and learning) how planets work," Jakosky said. "These are questions, about life, that everybody asks. Everybody wants to know. Because the public is interested. Because Congress is interested, and because we're answering important questions."

For the next several weeks, Geek Gestalt will be on Road Trip 2009. After driving more than 12,000 miles in the Pacific Northwest, the Southwest and the Southeast over the last three years, I'll be writing about and photographing the best in technology, science, military, nature, aviation and more in Colorado, Utah, Idaho, Wyoming, Montana and South Dakota. If you have a suggestion for someplace to visit, drop me a line. And in the meantime, join the Road Trip 2009 Facebook page and follow my Twitter feed.