Destination Mars (26 page)

M
arried to another JPL scientist, Joy Crisp can be found on off hours at her Princeton home quietly immersed in a science fiction book, often a David Brin title. She has been at work on the Mars Science Laboratory for years, acting as the deputy project scientist, but her path to Mars was not a simple one.

“I was a volcanologist, so I studied volcanoes on the Earth. I was doing a postdoc at UCLA, and a friend of mine said ‘I think there are people at JPL that are volcanologists, and there might be a postdoc position open there.’ I had no idea! I thought JPL was just a place where they studied space. I talked to them and sure enough they were using thermal infrared sensors to look at Hawaii. I started to do research at JPL with a group of people, and then Pathfinder came along and they needed someone who could work on the instruments like the APXS [alpha proton x-ray spectrometer], which measured the chemistry of rocks and minerals, and they said they needed someone that knew about geochemistry. I was one of the few people that had that expertise, so I got involved and it was interesting. I moved to the Mars Exploration Rover project, and now I'm on Mars Science Laboratory. So I transitioned from studying volcanoes on Earth to volcanoes on Mars, and I ended up doing all kinds of projects.”
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Of those projects, the Mars Science Laboratory is easily the largest to date.

“This is a very big project, so there's a lot of things to do. We must make sure the science team can carry out their investigations, keep an eye out for the things the engineers are doing that could affect science, and advise a project manager when he has to make decisions.

“[MSL] really is a stepping-stone beyond missions like Pathfinder and [MER], which were very geology focused and didn't really have any capability for looking at organic compounds and the building blocks for life. [The] Mars Science Laboratory is better equipped.

“Pathfinder was a technology-demonstration mission. It was a short-lived mission and we confirmed a lot of things we knew about Mars. We did measure some slightly higher silicon composition, so there were some ground truths right at the site where we landed. Spirit and Opportunity were a huge step in understanding because they were more capable, and because they lived so long. Opportunity is still going, and because of that, we've learned a tremendous amount at two very different sites. One thing that those rovers have done is to show us that there is definitely a diversity of geology on the planet and that we can redirect [the rovers] and find evidence of past water. With Opportunity, we found some rock layers where water was even flowing on the surface, depositing the grains, and also secondary water, ground water, was circulating through them, and cementing them, and making those little hematite spheres in them. So there were lots of clues.

“What we will really be able to do much better with Curiosity is to identify the minerals. We were struggling a little bit with Spirit and Opportunity; we could identify iron-bearing minerals with the Mössbauer spectrometer, but with other minerals, we had to guess somewhat. [We took clues] from a thermal infrared spectrometer as to what mineral combinations might be there. So when we get there with our x-ray diffraction spectrometer on Curiosity, we'll have a much better way to say what minerals are present in the soil and in the rocks that we look at.

“We're also bringing the instrument called SAM, Sample Analysis at Mars; and that one will be able to drill into rocks and find out [if any] organic compounds are present. We haven't tried to do that since Viking days, and when Viking tried to do that, it couldn't find any organics in the soil. We're going to have a more sensitive instrument. We'll be able to heat [the soil] up much higher and be able to look for organics at even a lower level and look at drilled rocks. It's still going to be pretty hard, and it's a remote possibility that we're going to find organic compounds on Mars, but we'll certainly have a better chance of doing it with this rover.”

The MSL rover is not designed to search for life, though. It will search for the basic elements that can support life: “We're not trying to do what we did with Viking, which was to look for life. [With Viking] after we got the experimental results, we scratched our heads and realized that we could think of a way for an inorganic substance to create those kinds of results. That wasn't the best test, and we realized how hard it would be to devise an experiment to look for life. We don't have an instrument that the science community can [agree on] to go look for life. So we're kind of taking a baby step in that direction, going slower than Viking tried, saying ‘let's try to find the organic compounds and measure those again in a better fashion.’”

So…is there life on Mars? The answer is unclear, but Crisp can hazard a guess: “We believe it's more likely that there was life in the past than life today because of the harsh environment today, but we're still going to go and…drill into a rock five centimeters [(two inches) to see if we] find organic compounds preserved in the rocks. We're trying to use techniques that we use on the Earth to look at the rocks and say ‘which one of these are most likely to preserve evidence of organic materials?’”

To collect these samples, MSL will use traditional, tried-and-true techniques, such as a sampler arm with a scoop and rock brush. But there is a new wrinkle in the mix: the rock drill. And getting powdered rock from the drill to the onboard lab in the
rover will be yet another challenge: “This is a huge new challenge that we have not tackled before. We did a little bit of this with Phoenix, where they had us scoop and deliver material into an instrument with the wind blowing. We learned a lot of lessons from [that mission], but we're trying something even harder with the rock drill.”

It's natural to assume that it must be frustrating for geologists like Crisp to work from so far away. To this, she responds: “Well, I'm a geologist, so I like to go out with a rock hammer and hit rocks and look at them. I want to know things like how did this rock form, what was it like when this rock was forming or altering, and so on. MSL is just the kind of mission that excites me; it's as if I could be there, because I'm drilling in the rocks, and then I'm finding out what minerals are in it and looking at it with a close-up camera. And this time it will be in color and higher resolution! In all of our sites we have layers of rocks so we can move through and see how things changed over time in Mars, so that's going to be interesting too.”

But still…commanding a machine millions of miles away is far tougher than doing it yourself. And the team must be trained extensively for this: “We had a science team test where we sent some people out to Arizona. It was a site that the team didn't know [the location of], and we set up a bunch of equipment that was like what we were putting on the rover. We started out by taking pictures and we put it into their planning tools. Everybody was working from their home institution around the world, and they started out with a bunch of pictures, and we told them, “here's your picture from orbit, you are here, it's day number 235; now start planning tomorrow and here's what you were thinking of doing.” Many of them have never done this before. A few of them were from the Spirit and Opportunity missions, but many of them had no idea what it would be like.

“One of the lessons learned was that we had no idea how frustrating and challenging it would be to do field geology so slowly.
When you are planning the next day's work, you have to argue with your peers on what steps to take. For instance, will the rover drive this way or that way, put up its arm or not, and so forth. We wanted those kinds of lessons to sink in so that they start getting used to it. Personally, after so many years of doing it myself, I just mentally accept that this is how it works. I'm very patient.”

So, given all this, would she prefer to go do it on-site?

“I wouldn't want to go to Mars myself yet because I'm just not ready to do that, it would be way too difficult right now. So I'm willing to do it this way, slowly, via computer. It's a different kind of challenge…can you work with your scientist friends to come up with the best plans to get the rover to do things, and then sift through that precious data to get the most out of it that you can. It's just a different kind of challenge. Like I said, I'm a patient person.”

And, as we know, patience is a virtue rewarded in planetary exploration. The secrets of Mars await.

J
et Propulsion Laboratory is seventy-five years old as of 2011. In that time, the campus has seen jet- and rocket-engine experimentation; construction of America's first satellite, Explorer 1; missions to the moon, Mars, Venus, Mercury, the sun, Jupiter, Saturn, Uranus, Neptune, as well as the asteroids Vesta and Ceres and the comets Tempel 1 and Hartley 2. And, with the passage of the Pioneer 10 and 11 and Voyager 1 and 2 spacecraft out of the solar system's boundaries, JPL is now officially in the business of interstellar exploration as well.

Of course, no one institution could do these things alone. JPL is funded by NASA and managed by the California Institute of Technology, also in Pasadena. The many missions it operates are done in cooperation with institutions all over the country and beyond. Notable among them have been Stanford, Cornell, the University of Arizona, the University of Colorado, and many others. Space is too vast, the job too huge for one agency to go it alone.

With the Opportunity rover still operational, Mars Odyssey, the Mars Reconnaissance Orbiter, and Mars Express still sending home data, and the Mars Science Laboratory on its way to the Red Planet, what lies ahead?

Currently, besides MSL, the lab is involved with parts of the James Webb Space Telescope and other Earth-orbiting observation platforms and is cooperating with the European Space Agency on other planetary missions. A lone Scout-class mission, MAVEN, is
scheduled for a possible 2013 launch. It is a small and inexpensive orbiter to study the Martian atmosphere. Beyond this…no other funded Mars programs exist.

There have long been plans for a sample-return mission, but this is a far larger funding requirement than mere landers and rovers, and so far NASA has not allocated the dollars necessary to design and build such a spacecraft. JPL is also working with NASA and ESA on the ExoMars mission, with an orbiter planned for 2016 and a rover for 2018, but the fate of this European mission is uncertain. And the United States would be a junior partner at any rate.
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So a reasonable person might ask: what does an agency like JPL need to do, beyond racking up decades of brilliant successes, most of which have far outperformed their designers' wildest fantasies, in order to secure future projects and funding? Said reasonable person might be stunned to find that such performances are not enough. The public at large, and Congress and the executive branch in particular, seem to feel that these bravura performances are the
minimum
expectation. They do not ensure future funds. And major failures, such as the Mars Climate Orbiter and Mars Polar Lander debacle, could bring down the whole show. The American public seems to have a short memory for success…ask any Apollo astronaut other than Neil Armstrong or Buzz Aldrin.

But there are plans. Which of them will be funded and developed remains to be seen; what follows are some of the more likely candidates for future Mars exploration.

The most exciting for most observers is the Mars sample-return mission. Long a twinkle in NASA's eye, a sample return will incorporate all the experience gained from the last twenty years of Mars landers and more. This craft must descend to a pinpoint landing, discharge a smart rover with the ability to handle larger samples, be capable of acting as a stable launch platform and then launch a rocket able to depart Mars with a load of rocks and soil and navigate back to Earth, including atmospheric reentry and
landing. It's a huge and daunting undertaking, and may require international partners such as Europe, Russia, and perhaps newcomers such as India or China to succeed. But in the end, it seems likely that a successful sample return will be funded primarily by NASA and run, of course, by JPL. A Martian sample studied on Earth, with all the luxuries of a fully equipped laboratory, will yield answers to long-held questions about chemical composition, the existence of organic molecules and much, much more than could ever be accomplished robotically on-site.

NASA is also still considering a series of ongoing smaller missions. These include ideas such as Mars airplanes, large instrument-toting balloons, and more landers similar in scope to Phoenix. Both the balloon and the airplane proposals are for craft that would stay aloft in the Martian atmosphere for weeks, if not months. These airborne platforms would allow for a close-in observation of the many points of interest spotted from orbit. Originally, many such plans had fallen under the now-canceled Scout program.
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Some may be reclassified into NASA's ongoing Discovery program.

An astrobiology-laboratory rover has long been on the drawing boards. Building on experience gleaned from MSL, such a rover would represent the first true search for life on Mars since Viking. But it would be far more sophisticated than Viking or even MSL, and would likely be tightly focused on microbial life. If MSL is successful, look for this advanced rover sometime late in the decade.

More orbiters will doubtless follow MAVEN, as there are always increases in imaging and sensory capability to exploit in a new mission. Once sufficient improvement builds up, there comes a point of critical mass that drives a new Mars orbital project. Before long, Mars orbiters should match the capabilities of current Earth-orbiting spy satellites.

Finally, further exploration of the poles and deeper Martian soils is expected. The one major class of geological investigative tools that has not been included on a flight to date is a deep-soil
drill. This will be another leap in mass delivered to the Martian surface, as rock and soil drills are heavy. The technologies explored in MSL should aid in the design of this unit.

But these are in the future, and the future of space exploration is a fragile thing. It is tempting to consider JPL and NASA to be forever; to be eternal institutions. But this longevity is far from assured. With financial crises rocking the globe, and the US federal government seeking ever more ways to cut spending, there are few sacred cows. Science is never safe from funding cuts. NASA is still struggling to recover from the loss of the Constellation project to return to the moon. The space agency is left with a crew capsule, Orion, but currently has no rocket to place beneath it. All plans for a replacement launch vehicle are, at press time, far from reality. And even if funded, all NASA projects are subject to cancellation at the whim of an ever-fickle Congress.

As regards the continued investigation of the solar system, one major failure on the order of a mission such as MSL could, in the opinion of some, spell the end of JPL and unmanned exploration. More measured consideration sees darker times in such an event, but an eventual return to space by JPL in some form. But it would be a tortuous path.

Of course, this is all conjecture. But if the short history of space exploration is any guide, it is a seemingly easy item to trim, if not outright cancel, from the national agenda. And this is a shame, because the exploration of space is something the United States has consistently done better than anyone else, and it is one of the few programs in which the money spent is returned, at a rate of almost 100 percent, into the American economy. Jobs and education benefit; engineering and science are enhanced. It's a classic win-win scenario, but one that is increasingly hard to sell to the American public at large.

Time will tell.