SCV NEWSMAKER OF THE WEEK:
Richard Cook, Deputy Project Manager
Mars Exploration Rover Program (NASA/JPL)
Interview by Leon Worden
Signal City Editor
Sunday, November 16, 2003
(Television interview conducted Sept. 29, 2003)
Note: Richard Cook was deputy project manager on the Mars Exploration Rover Program at the time this interview was conducted. He was promoted to project manager soon thereafter.
"Newsmaker of the Week" is presented by the SCV Press Club and Comcast, and hosted by Signal City Editor Leon Worden. The half-hour program premieres every Wednesday at 9:30 p.m. on SCVTV Channel 20, repeating Sundays at 8:30 a.m.
This week's newsmaker is Sand Canyon resident Richard Cook, deputy project manager for NASA/JPL's current Mars Exploration Rover program.
Signal: Based on what is known today, do the folks at NASA and JPL believe some kind of life exists on Mars?
Cook: I think it's reasonably safe to say that there's not life existing on Mars right now. We sent some missions back in the mid-'70s to look for signs of life
and didn't find any. It's possible that in very isolated locations there might be life. It's difficult to predict.
What we're really interested in looking for, though, is evidence of life in the past. It's pretty clear that some time in the history of Mars, it was probably warmer and wetter than it is now. Those two conditions, whenever we find them on Earth, we tend to find life. Since we believe that to be the case, we're going to look for evidence that there was life there, and that will allow us to at least show (that) sometime in the past, it was there.
Signal: Would this be microbial life or something more advanced?
Cook: It's probably going to be microbial life, because in order to develop into something more complicated than that, (it) would take a fairly long time. Just showing signs of microbial life, though, would show that it's possible. We are still searching for some evidence that outside of the Earth, there is life of any kind, so it will be a good first step.
Signal: How will the rovers expand that understanding?
Cook: The rovers are looking
for signs of it in the past. Probably the best way to do that is to look for evidence of water, that water existed in liquid form on Mars in the past.
There's lots of water on Mars now. It's mostly in the form of ice. There's some water vapor, but mostly in the form of ice at the polar caps but what we want to look for are signs that there was liquid water. Because again, on the Earth, wherever we see liquid water, we generally find evidence of life. If liquid water exists for a long period of time, that would lead you to believe that at some point during that period of time, life developed.
The signs for water are things like mineral signs of water. If you go out and look at sedimentary rock formations or go out in the desert north of here and you look at dry lakebeds, you'll find minerals that are only formed in the presence of standing water.
Two identical rovers, launched in June and July, are scheduled to land Jan. 4 and Jan. 25 on Mars, where they will explore for evidence that water and life was present in the past.
One of the places that we're going to go seems to be a place where there might be minerals that were formed in a water process.
One lander is going to a mineral-rich site; the other one is going to what looks like an ancient lakebed, where there is a large crater formed by an impact several hundred million years ago. It has a stream bed that we can see from orbit that looks like it's flowing into it from the higher, mountainous areas that are around it.
It really looks like, if there was going to be a place where there was a lake on Mars in the past, this would be a prime candidate. So we're kind of hedging our bets (with) both a topographical place where you can find water, like a lake, as well as a mineralogical one.
Signal: What are your responsibilities as deputy project manager? You're the No. 2 person in the rover program, right?
Cook: That's right. I got to have the opportunity, prior to launching the two spacecraft, to be responsible for building the two vehicles. I spent about 2 1/2 years leading the team that first, designed, and then built all the little pieces, and then put it all together and tested it prior to launching each one of them last June and July.
Now, we are preparing to get ready for operating them on the surface. That's a very intensive period of about four months where we'll be operating the rovers every day, seven days a week for four months, to have them explore around the places where they land
Each one of the two rovers we treat independently, so I'm trying to make sure we don't collide with ourselves, so to speak, whenever we need resources like facilities and money and things like that. I'm trying to keep the two different vehicles well oiled as far as their operations are concerned.
Signal: A few other local residents are on the management team, including the person in charge of what the rovers do once they land?
Cook: That's right. In fact the woman, Jennifer Trosper, lives here in the Santa Clarita Valley, and she's going to be the mission manager for one of the two rovers. That means she, every day, determines what is going to happen that day, the next day, in conjunction with the science team, to make sure that we drive as far as we need to drive, and sample and look at the rocks the way we need to, and basically keeps the vehicle operating throughout the mission.
Signal: Can you go through the process from launch to landing?
Cook: Sure. We launched the first vehicle June 10 (from Cape Canaveral in Florida). So it's about halfway to Mars. We're launched on a Delta rocket. That's a standard rocket that we've used to launch communication satellites and other things.
It's a three-stage vehicle. It comes up from the Earth; the first stage is used to essentially get you up 10 miles or so, and then it falls away, and then you go off with the second stage. Eventually the vehicle is exposed, comes out of the faring, and it's ready to start its flight to Mars. The last piece of that is where the third stage of the rocket fires and it sends us on a trajectory that's going to Mars directly from the Earth.
The vehicle then spends about seven months and it's the seven months that we're in right now not doing very much. It communicates with us every few days, and we occasionally send up commands to check out pieces of equipment. But there's not a whole lot to be done during that period of time.
Signal: Once the rocket fires, it just goes? It's not under propulsion now?
Cook: No, it's not. The only thing that we need to do along the way is, we need to do fine course correction to get it to go right toward Mars.
The total distance it travels is about 250 million miles. So it goes quite a long way. And when we get to Mars, in order to hit the top of the atmosphere with exactly the right speed and at exactly the right point, it's got to hit about a one-mile little spot, if you can imagine that. It's traveling across this enormous distance and hitting a very accurate spot when it gets there. So to get there, as we're going along, we have to nudge its path. It's pretty much flying on its own, but occasionally we have to redirect it. We've done two of those little redirection maneuvers, and we have three more to go.
The spacecraft has the easy time, frankly. The people on the ground have the harder part of it, because we are spending all this time getting ready for once the thing gets close to Mars and lands. The spacecraft is just flying along very peacefully. We're running around, trying to finish the software and to build all of the tools and the things we need to make it work once it gets on Mars.
This mission is based in large part on the Pathfinder mission that flew six or seven years ago, in '96 and '97. When it gets right up close to Mars, instead of going into orbit, it just goes right into the atmosphere, straight from the approach. It hits the top of the Mars atmosphere going about 15,000 mph, and within about six minutes it's down on the surface.
We call that the six minutes of terror. We have this seven months of boredom followed by six minutes of terror
The rover is encapsulated inside an entry capsule. It looks very much like the Apollo entry capsules. That entry capsule hits the top of the atmosphere. On the front side it has a material that will protect it against the extreme heating that it sees as it slows down very rapidly in the atmosphere. So for awhile that thing protects us. There is a big stream of hot gases coming out the back, and the aeroshell slows it down to where we can deploy a parachute. That's one of the advantages of landing on Mars as opposed to on the Moon: You can use the atmosphere to do a lot of the work for you
The parachute is about 40 feet across. It's a very large parachute, and it's deployed supersonically. The vehicle is going about Mach 2 when it deploys. The parachute comes out, slows the vehicle down some more. But even then, there's the old saying that it's not the fall that hurts you, it's the impact. It's really the last 10 feet where the vehicle comes down to rest on the surface that's the hardest part.
What we did on this project, sort of inheriting from Mars Pathfinder, was to build this airbag system, this sort of beach ball. As the vehicle hits the ground it's protected by a set of airbags similar in some ways to what's in cars, although a lot more capable than what's in your car. Those airbags are there to protect it as it hits the surface because there are rocks everywhere, and we want to make sure that we can protect the vehicle from those.
Signal: It's still going to hit pretty hard, isn't it?
Cook: It is. It's going about 30 (or) 40 mph when it hits the ground. And actually in between the parachute slowing us down and the airbags hitting the ground, there's a set of rockets that fire, that slow us down even more before, at the very end, the whole vehicle hits the surface and bounces around before it finally comes to a rest.
At that point, we hope to get communications back from it, saying that everything worked fine. From that point on
first the vehicle has to unfold so that the rover's exposed. In order to fit this big rover inside this little bitty capsule, it's all folded up. So like a transformer, it's got to stand up first, and then it deploys these little appendages and things, and that takes about a week before we're finally able to drive it off onto the surface of Mars. Then we'll spend about three months driving around.
This vehicle we expect to go half a mile to a mile, maybe, if it lasts for a very long time, whereas the Pathfinder rover, which was quite a bit smaller, it lasted (more than) three months, but it was only able to drive about 100 yards.
Signal: This one is only supposed to last for three months, also?
Cook: It is. Although, generally, these things work out where we design it to last for three months, and to do so, you end up adding a lot of margin to make sure that it actually lasts for three months, and then in reality it lasts for a lot longer than that.
Signal: So Pathfinder, from the mission standards, was wildly successful.
Cook: Yes, it was.
Signal: What was your role on Pathfinder?
Cook: I was the mission manager on Pathfinder, so I got to lead the operations team responsible for the day-to-day activities that were conducted once the vehicle got on the ground.
On that mission, it was both a lander that stayed in place, plus a rover that drove around. It was a neat mission because we got to see what Mars looked like in that particular place for the first time, plus we got to drive this vehicle that was the first-ever rover on the surface of another planet.
Signal: How do these rovers compare?
Cook: The Sojourner rover that we flew in '96 was about the size of a microwave oven. This vehicle is about the size of a John Deere lawnmower. So it's quite a bit bigger.
Signal: And more capable?
Cook: It is, absolutely. Besides being able to drive a lot further, instead of two cameras it has 10 cameras on it, so it's got eyes looking off in every direction, and it's got a much more capable set of science instruments than what was on Pathfinder.
Pathfinder was principally about demonstrating the technology of landing and then driving. We're building on that basis to do a lot of good science, as well.
Signal: The new rovers are going to be looking for water; Pathfinder's purpose was to examine rocks?
Cook: Yes, although again, to look for geological signs that water was there in the past. It's just that it was principally a technology demonstration, so we were trying to build the basic building blocks that then we could use to do more complicated missions.
Signal: The subsequent Mars Polar Lander and Climate Orbiter in 1999 weren't quite as successful as Pathfinder.
Cook: No, they weren't. We learned a lot from that experience. I think one of the things that we have been trying to do over the last 10 years or so is to try to redefine the bar as far as how inexpensively and how quickly we can do these projects. Sometimes in our zest for doing them as efficiently as we can, we push the line too far.
Signal: There were investigations into the loss of the Polar Lander and Climate Orbiter. One report advised tellingly, "If not ready, do not launch." What exactly does that mean?
Cook: What it means is that this is a very unforgiving business, so to speak. You can do 10,000 things right, and it only takes one thing to go wrong, and that's it. So to make sure that you have all those 10,001 things right, it takes you a fairly long period of time.
It has taken us three years to build this spacecraft, and even that was with a fairly accelerated pace. We try to do things very rapidly. But when you do things in a rapid fashion, you've got to have a lot of people. So you either need to have a lot of people or a lot of time. It's hard to do both (when you) have very few people and not very much time.
One of the things that was a lesson from the '98 Polar Lander mission was that you need to be careful and make sure that you're not trying to do it too rapidly without a compensating number of people to deal with the fact that these things are very complicated.
And it's a one-time thing. It's not like we get the chance to build one, and then if it doesn't work, build it again. We're always trying to push the state of the art, to do something that hasn't been done before. You just have to be very careful to not push too hard.
Signal: Is there an emphasis on quick, inexpensive programs that are smaller in scope than, say, an Apollo mission?
Cook: Yes, there is, although on this particular project, the Mars Exploration Rover project, we got effectively whatever we asked for as far as the people. JPL and NASA gave us the best and brightest, and gave us the resources that we needed to do the job right. They recognized that when this project was started three years ago, it was going to be difficult. Just that alone, getting it done in three years, was going to be a challenge, so they compensated for that in other ways, by not making we're not trying to spend more money than we need, but they weren't going to be pound foolish about it. To a certain extent, they were going to give us what we needed.
From our point of view, we had the resources that we needed. Time was the big challenge, but in getting to the point where we were able to launch, I think we managed to meet that challenge and still deliver a quality product on its way to Mars.
Signal: What are the various science objectives of the current rovers?
Cook: The overall objective of the program is to look for signs of water in the past. And if you find evidence of water, then you can draw the connection that there was likely life there in the past.
There are two sets of instrumentation, two groups of instrumentation, that will help us do that. One is a set of what we call remote sensing instruments, such as cameras and what we call a thermal emissions spectrometer, which is a fancy name for something that is like a camera that sees in infrared wavelengths.
Those two look out from the rover. They're able to look at the rocks and the soil around the rover and from afar, understand what kind of minerals the rocks have within them. There are certain minerals that are formed in the presence of water that you don't see, for example, formed in a volcano. So if we could find sedimentary rocks, or if we can see hematite, which is a certain kind of mineral that is formed in water, all of that would be good evidence that water existed there in the past.
That is looking from afar. The other thing we want to do is to get up really close to the rocks. To do that we actually have added to the rover an arm, which is about two meters (or) five feet long, fully articulated, where it can reach out and touch anything in that volume out in front of the rover.
There are actually four instruments on the end of it. Two of them are spectrometers a different kind of spectrometer which will tell us more about the elemental composition of the rocks,
helping to establish the provenance, we call it how the rocks were created, whether it was in water or a volcano.
We also have a microscopic imager, which we can hold up very close to it so we can see the fine-grain structure in the rock as well. From that, the geologist can tell, was it sitting in a lake or was it in some other kind of a rock field?
And then the final one is the most interesting, at least from my engineer's perspective, of all: It's what we call the RAT, (which) stands for the rock abrasion tool. One of the things that we learned on Pathfinder was that if you go out to the desert in California
you'll notice after awhile that all of the rocks have this sort of sheen to them. They're shiny, a little bit, like they've been varnished. That varnish is called desert varnish. It occurs because the wind blows all the time, it blows these little particles of sand along, and that basically does this sanding. On Mars the same process goes on. If you look at the varnish out in the desert in California versus breaking the rock open, you'll find that the outer surface, chemically, is the same for every rock, independent of what's inside.
The rock abrasion tool, or RAT, scrapes off the top quarter inch of sandblasted rocks so a microscopic imager can take a look inside.
Signal: It's sandblasted.
Cook: That's right. The way a field geologist works here is that they'll go and break open the rock and they'll look inside of it. It turns out, that's pretty difficult to do on Mars. So what we've brought along is really a very sophisticated Dremel tool that basically drills down. It uses a set of teeth and we put it up against a rock and it can drill off the top quarter inch or so of this varnish and we can look to see what's inside the rock.
That's going to be something that's pretty interesting to try out, this little drill. That'll be a first-time thing for this project.
Signal: The literature mentions that one objective is to prepare for human exploration. When is that going to happen?
Cook: That's a good question. I think that we've got a number of other challenges in front of us still to go. I think we are trying to lay the groundwork in the long run for that sort of stuff. Certainly we're still able to learn a tremendous amount with sending robotic spacecraft, and I think that's what we're focused on at least for the next 10 years or so.
I think that will culminate, hopefully in the next decade when we do the Mars Sample Return mission, which is it's great to go out and send robotic spacecraft with their own instrumentation; you can tell a whole lot (with) that but if you can bring rocks back, as they've done with Moon rocks, there are amazing facilities here on the Earth for doing analysis of what the rocks are made out of, which you just couldn't ever put onto a spacecraft and send off to another planet.
So the big objective of the robotic mission is to bring back a sample, which we then can analyze here on Earth.
Signal: When is that mission supposed to happen?
Cook: It's probably going to happen 2012, 2014, in that time frame. It turns out, that's a very complicated mission. Getting there is hard enough; you also have to take a rocket with you so it can bring the stuff back. It's going to take us awhile to build up our capability to do that.
Signal: Some people believe too much is spent on the space shuttle and not enough is put into Mars. What's your opinion?
Cook: We seem to have a lot right now, so I'm not sure I would agree with that. I think NASA is trying to balance different programs, and trying to have a strong science program at the same time as keeping human exploration going.
I think that all of the last year's experiences indicated that it's hard to do that. To maintain an active space science program as well as an active human exploration mission is difficult to do from a dollar point of view, but I think that we have learned to become more efficient. We've learned to figure out ways that we can share information with each other. I think that's going to help us over the long run.
I do think that to do something like to send humans the human exploration program is just sort of barely hanging on, with the funding they have to do something like a (manned) Mars mission or even another lunar mission would take a tremendous amount of additional money beyond what they've been currently getting.
I think one of the things that is stymieing us from getting where we want to get long-term, is that there are just not the resources there. I hope that when the space station reaches the point where it's fully built, that there will become more (resources) available to start a Mars mission. But I still think it's 20 years off, minimum. As we've learned this last year (with the loss of the space shuttle Columbia), there are a lot of issues that still have got to get worked out about getting safely to orbit for humans. So I think we're going to go backwards a little bit here before we go forwards.
Signal: Are there tangible benefits to sending humans to Mars? What's better, man or machine?
Cook: It's like saying what's better, apples or oranges or apples or bananas. They both have their place, and I think that certainly robotic spacecraft can accomplish a lot. They're more inexpensive, and I think that they sort of scratch that exploration itch which I think everybody has.
It's difficult to argue, though, about seeing an astronaut on the surface of another planet or on the surface of the moon. I was a kid when Neil Armstrong landed, and it was certainly very inspiring for me, one of the tings that got me into this business.
I think people can project much easier with other people there than they can with machines, but as we found out on Pathfinder, they can project pretty well with machines, too.
The rovers are scheduled to land Jan. 4 and Jan. 25, 2004. Images courtesy of NASA/JPL.
See this interview, with numerous NASA images and animations, today at 8:30 a.m., and watch for another "Newsmaker of the Week" on Wednesday at 9:30 p.m. on SCVTV Channel 20, available to Comcast and Time Warner Cable subscribers throughout the Santa Clarita Valley.