Lyn Doose

We had the Pioneer 10 encounter with Jupiter in December of ’73. It was the first spacecraft to get out to Jupiter, and I was part of the team that commanded the spacecraft and analyzed the data; looked at both the uplink and downlink. It was really neat. We got to sit at Mission Control up at Ames Research Center, and we’d monitor the commands to make sure they went out to the spacecraft. It wasn’t like today when you have these vast computer memories on spacecraft. Basically the instrument couldn’t remember anything but what it was told last, so we’d have to send commands out, and there were tens of thousands of commands, and everything was on IBM punch-cards. It was a different time.

On Pioneer we worked in teams. We had one guy monitoring the commands that went out and another guy monitoring the commands that came back, and occasionally radiation would affect the instrument and it would go wandering off doing something entirely different from what it was supposed to do. We had to have the uplink guy, the guy sending the commands, take corrective actions. But the light-time was an hour and a half so we’d lose an hour and half of observations whenever that happened.

Then Pioneer 11 got there a year later in December of ’74 and both missions were big successes. I was working on the red spot and I actually programmed up the sequence to take photos of the red spot. The photo that resulted from that line-up got on the cover of Scientific American, so that was gratifying.

Pioneer 11, which sling-shotted its way around Jupiter, went on out to Saturn. It finally arrived at Saturn in ’79, so the seventies was just this long sequence of planetary encounters. Really great stuff, really gratifying, and for somebody who just got his degree, it was just fabulous. We saw the F-ring on Saturn for the first time. Nobody had ever gotten ground-based pictures that looked like that, at that time. It was just very exciting.

Martin Tomasko

For the Pioneer encounters, these fly-bys of Jupiter, we had a series of maybe 20 thousand commands that we had to write and figure out where to point the telescope and how to make the pictures. The spacecraft was a spinning spacecraft, so there was a little one-inch telescope where the angle from the axis of the spacecraft could be varied—could be stepped—in half-millimeter steps. As the spacecraft rotated, it would sweep out one line of photometry across Jupiter, and then you would step the telescope half a millimeter, and then scan out a second line and scan out a third line, and this way build up an image over a period of an hour or two, with scan lines one after another.

Not only that, but the round-trip light time to Jupiter is like an hour in a half, so you have to transmit the command 45 minutes before you want it to take effect, and then 45 minutes later you can check off that it actually got there and took effect and the telescope is doing what you told it. The other thing about it was that Jupiter has powerful radiation belts, trapped energetic particles, and these would whack the instrument. Commanding the instrument was kind of like telling an old, senile guy to go to the store and get a quart of milk. You tell him, “Go to the store and get a quart of milk,” and he starts marching off, moving in the direction you want. He knows he’s going to the store and he’s getting his quart of milk. About halfway through the images: “Where am I going? What do I want to do?” It would reset the registers when the energetic particles hit the instrument, so the instrument would start moving the way you wanted, and then halfway through, it would just forget its mind. It would just go off doing something else completely different.

We had a crew of guys around the clock, three shifts of guys, checking off this list 20 thousand commands as each one got transmitted, and the other guy with a downlink book, checking off that, yeah, the spacecraft did that, it took effect. Then finding: No, that command didn’t take effect, and in fact, that instrument is off doing something else. But that’s what it was doing 45 minutes ago, and in the meantime you sent an hour and a half of commands to the instrument to do something different, so it’s now going to be starting at the wrong place, and those are going to be bad. So now you have to figure out: What commands do we have to insert in the sequence to get back on the track and put the instrument back in and reconfigure it to do what we want it to do?

It was actually a major effort. One of my first jobs here was to figure out how to generate this command sequence, and then train the guys who were going to monitor the uplink and the downlink, and make sure we actually got some pictures from Jupiter in the process. It was really a heck of a challenge, and a very different flavor than today. Today you write a command sequence and it gets loaded into the computer and it goes zip, and it’s up there, and inserted into the machine, and it does what it’s supposed to do. It was quite a different flavor.

The first flyby of Jupiter had an imaging device on it. The instrument did spin-scan imaging. But of course all the while that it’s building up an image, it’s getting closer and closer to Jupiter. So the image is not like a snapshot that you take, but it’s accumulated over an hour and a half, and it’s got ferocious geometrical distortion.

To make it look like a picture, there was a whole other set of processing that had to be done. There was no Internet, so this data was collected at Ames Research Center, and put on tapes. The tapes were flown back to the University of Arizona, and they went through some complicated geometrical rectification step, then flown back to California, and then they could be displayed and people could see the pictures.

They were beautiful, and some of them were really quite spectacular. But you have to understand that Jupiter is a fairly bright object. The limitation of the kind of imaging you get with a ground-based telescope is the scintillation of the atmosphere. The atmosphere has turbulence and refracts the image, and doesn’t make a very sharp image. But if you take thousands of images, you can find instances when the atmosphere is fairly still, and you can get occasionally very good images of a bright planet like Jupiter from a ground-based telescope.

The images we got were better than the best ground-based images, but not by such an enormous knock-your-socks off factor. The main advantage was that we flew around Jupiter, and Jupiter’s far away from the Sun compared to the Earth, so we only see Jupiter essentially illuminated face-on. But the spacecraft flew around and could look at Jupiter as a crescent, at ninety degrees phase, and we could observe Jupiter in all these different new geometries that we’d never seen before, and we could learn something about the nature of the cloud particles by flying around and looking at it from other directions.

Lyle Broadfoot

We did Mariner 10 while I was out at Kitt Peak. That one went to Venus and then to Mercury. We went around the planet, and then around the Sun to shoot back to Mercury. Orbiting Mercury, we always came back to the same place at the same time. The last time we passed, we ran out of gas. The control is done by gas jets.

They actually flew it around the Sun the last time using the solar panels to stabilize it, because they knew they were going to run out of gas. So they used the solar panels to fly it like a sailboat. Then as they approached Mercury, they turned on the gas jets and stabilized it, and we did our experiments until the power passed. 

Robert Strom

I got involved during the Apollo program in Mariner 10, which was the first flight to Mercury. That was a reconnaissance flight to just see what was on Mercury, and to plan for an orbiter. It wasn’t supposed to be a definitive mission; reconnaissance was all it was. That was a successful mission.

Nobody’s ever been back to Mercury since 1975. I was on the planning committee to send an orbiter there. It never happened, for two reasons. One, people looked at Mercury and said, “Oh, well, it’s just like the Moon, so it’s not interesting.” Which is baloney, but that was the perception at the time. The other reasons is, to send a mission to orbit Mercury is an extremely difficult task, and extremely expensive. They haven’t been to Mercury until recently [with the MESSENGER mission].

Alan Binder

I was a Principal Investigator on the lander camera team. The first landing of Viking 1 was early in the morning, about seven o’clock. This was prime time for the morning shows. Our team was divided into two parts; uplink, which was choosing the pictures, laying out the sequences, getting the computer programs written so we could get the pictures we need; and then the downlink guys. I was head of uplink.

We were very busy, as you might imagine. It took in those days two weeks to develop the load to go up to the spacecraft. So we had to pre-program for two weeks, without even knowing what the surface was going to look like, the sequences. I had to see those pictures immediately to begin to modify for two weeks ahead.

So I was eagerly waiting to in my area to get these first pictures, and Tim Mutch came in and he said, “Hey, MBC wants somebody for the Today Show, and I want you to do it.”

I said, “I’ve got plenty to do.”

He said, “Come on, this is important.”

So I had to go over to that TV place. We had successfully landed; we knew we were down. The first thing that happened was our number two camera was supposed to come up—it was a slow-scan camera. Nothing like what you see now where the pictures just come down, boom, boom, boom. It was a facsimile camera, so it did one scan at a time in the vertical and slowly it would rotate.

My God, this panorama began to come in front of me, and there were rocks all over the place, and I didn’t know what to say. I was just dumbfounded by the beauty. The camera guy kept saying, “Dr. Binder, say something!” and I would say something and I would look at these pictures. That was just exciting—not that I was on TV but that first picture from the surface of Mars was just unbelievable. Those were the good old days.

Victor Baker

We had a lot of data from the Viking mission. I was a guest investigator on the orbiter imaging team for the Viking mission, so I was studying this from the point of view of a geomorphologist and a geologist. This was leading to a lot of ideas about what it might be that had operated in the past on Mars to create the conditions that allowed flowing water, and particularly rather condensed flows of water in the form of these giant floods that made the Martian outflow channels.

As a geomorphologist I’m interested in the surface form and processes that operate on a planet. Images are absolutely essential to interpreting that. But of course the images that were initially just a visual range of perception have now been augmented by images that are showing us spectral properties. For example, with Venus we had images that were showing us radar reflectances. These are all images, but they may not be as easily interpreted by the general public as a regular picture-type image.

I find immense scientific value in them, and it’s quite a long story as to how that works. One would have to understand how it is that we do science with images. But a brief statement of that is that the images relate to a larger context, the features of interest. We see them in relationship to other features in a sort of spatial relationship that has to do with their causes and their overall pattern.

So as geomorphologists we use that understanding to get further understanding on how the planet works, and particularly the surface of the planet. We combine that with other information, of course, but images—that’s essential.

Science is not an individual activity where we do things that just inform ourselves. Science is a community activity, because that community is what validates or thinks about the relationships of what we have discovered to what other scientists have discovered. So I benefit from seeing what they do; they benefit from seeing what I do, and it’s all part of an endless quest for the truth of things.

No one is going to be critical of you even if you make a mistake. If you’re similarly dedicated to that process and you’re honestly engaged in doing it, you’re all part of the same spirit of investigation. Even though you might be using somewhat different tools and methods and even somewhat different ways of thinking about things, you all come together in a common spirit of searching for just how it is remarkable things like the surfaces of planets came to be the way they are. 

Martin Tomasko I proposed for a Venus entry probe mission, Pioneer Venus, and we got selected and we built a photometer to measure the penetration of sunlight through the atmosphere of Venus as the probe comes down in a parachute through the atmosphere of Venus. How thick are the clouds? How much sunlight gets absorbed in the clouds? How much gets absorbed down to the ground and can drive the greenhouse effect that would be responsible for the high temperature on the surface of Venus?

We found something like two and a half percent of the sunlight makes it through the clouds and gets absorbed at the ground, and that’s enough, we think, with a thick thermal blanket in Venus’ atmosphere, to explain the greenhouse effect.

But it was interesting, too, proposing for that mission, getting selected, working with an aerospace contractor to built the electronics. The optics was designed here, actually in Optical Sciences Center. The sensor head was built in the Optical Sciences Center; it was calibrated here in Tucson, and then delivered and flown. We finally got to answer the questions ten years later that we proposed in the original proposal of how much sunlight gets absorbed in Venus’s atmosphere. That was really exciting, too.

Lyn Doose

Marty Tomasko was my thesis advisor. We got a contract to do Pioneer Venus, which came along in ’78. It was an entry probe. We had an instrument on Pioneer Venus called the solar flux radiometer, and it parachuted down into Venus’s atmosphere and it got down to about, I don’t know, 20 kilometers or so, when apparently the solder melted, and it quit working; it got too hot. But we built that here largely, we did all the testing of it here, and I had a lot of experience in building and flying instruments by that time.

Peter Smith

I had worked with Marty Tomasko when I was a student. After graduation, he hired me to help calibrate an instrument that he was sending to Venus. I worked for two or three months helping him calibrate this instrument. It was delivered to the spacecraft team in June, the launch was in August and it landed on Venus in December. A month later we had a paper in Science magazine. A few months after that I was writing programs for the thermal balance of the Venusian atmosphere, and thought of myself as a Venusian weatherman. This is great, what a wonderful career, exploring planets.

Bill Sandel

There were two spacecraft, Voyager 1 and Voyager 2, launched about a month apart in 1977. They visited Jupiter, Saturn, Uranus and Neptune. For Jupiter, both encounters were in 1979. The spacecraft were spaced out by that time, so there was a Saturn encounter in 1980 for Voyager 1 and 1981 for Voyager 2.

At the Saturn encounter, Voyager 1 was targeted to go very close to Titan. The close approach to Titan required a trajectory that took it out of the ecliptic plane, so it wasn’t possible to retarget that for any more planets. But Voyager 2 didn’t have that restriction, based on its trajectory. So it was possible to keep it in the ecliptic plane after the Saturn encounter, which was the end of the nominal Voyager mission, and it continued on to Uranus in 1986 and Neptune in 1989.

Lyle Broadfoot

With Voyager we made several discoveries along the way. We discovered the Io plasma torus, which occupied our time as we came in to Jupiter. We had a slit instrument with 128 detectors that were scanning across Jupiter, so if there was anything going on we might pick it up. What we found was the torus, and the torus is out at about five Jupiter radii. The source of the torus is Io, the satellite.

As we came in we saw this ultraviolet emission around the planet. If we hadn’t had an ultraviolet experiment we wouldn’t have a clue and wouldn’t know it was there today. So that was a big boon for our program.

We were looking across and we saw this thing and we modeled it as we approached. Now the particles and fields instruments are in situ instruments; you have to pass through the atmosphere in order to make the measurements. We were lucky on Voyager, saying, “Hey, you guys, there’s some high energy particles in orbit around Jupiter.” We went on telling them this as we came in, and finally I guess we had them convinced. We were flying close to Io, and a couple of the instruments were saturated and we had to turn down the gain, based on our measurements, because we told them what the density was and all this.

I, as the PI, had a dream one night. I told those guys that Io was volcanic. Unfortunately, we decided not to bring this up, because we thought it would be more trouble. There were a couple of theoreticians, and I think the problem was they couldn’t see how to get material off the satellite and into the atmosphere.

After we got by and I actually had come home, and was settling down here, I got a call from one of our team members at JPL. He said, “Guess what? Imaging has seen plumes, volcanic plumes, on Io.”

It took five or six days to fly by Jupiter because it’s such a big planet, so there was stuff going on every day. Every day there was a press conference, and each of the experimenters would present whatever they had seen the previous day. It was a lot of work. No sooner did we get through a press conference than we started having to figure out what to say the next day. Then we sent that off to the drafters and all that to get the artwork done. Yeah, it was a busy time.

Jay Holberg

There were two Voyager Ultraviolet Spectrometers, one on each spacecraft. By the time Lyle Broadfoot’s group joined LPL, the Voyager had passed Jupiter and Saturn, and we were headed for Uranus in 1985 and Neptune in 1989. It was a very, very busy time.

My involvement with the instrument was that I was the person who did the scheduling of the observations that were made, and was responsible for helping with people at the Jet Propulsion Lab to design the observations, making sure they went smoothly at the planets.

One of the principal things I did was I was responsible for using the instruments during the cruise, between Uranus and Neptune and so forth. In that respect I found that the instruments were extremely useful for ultraviolet astronomy. Since that was kind of my background, I used those instruments to make lots of observations of stars and the interstellar medium and so forth.

The instruments were designed and used for observations of the planets, but those observations occurred during a very brief period of time during the encounters, and you had all of this time in between. Those instruments were extremely valuable in helping to understand a part of the spectrum, the extreme ultraviolet and the far ultraviolet, that wasn’t being addressed by NASA at that time.

One of the biggest highs was when we were approaching Saturn, and they were taking all these pictures of the rings of Saturn and so forth. You could see all this structure in the rings. There were these papers that predicted the structure, or portions of the structure, has to do with the orbital resonances of the moons.

I was intrigued by this because I sat in a meeting and listened to these people talk about this. But no one really knew the scale of these pictures, so you couldn’t say, “Ah, that resonance there is due to that moon over there.” I knew nothing about planetary rings, but I had worked to get our instrument to watch a star go behind Saturn, and you could actually see the star through the rings. You see the light drop out and come back and drop out and come back. It’s called occultation.

That observation was the primary observation of another instrument on the spacecraft, but I realized that we could use our instrument just as well. So I got the observation designed so we were included in the observation. I got the data back and I was very intrigued by it—all this structure—so I just sat down with a pencil and piece of paper, and I knew what the trajectory was, and I worked out where everything should be. All of the sudden it all fell into place, because there were predictions of where these things should be. You could see just about every prediction lined up with one of these features.

Lyle Broadfoot

We got a program going under NASA, which was under the rocket program. It was an ultraviolet telescope [UVSTAR, the Ultraviolet Spectrograph Telescope for Astronomical Research]. We observed short of 1200 angstroms, and that region is—there’s no transparent optics. So it’s an issue of building fairly specialized instrumentation.

In that case, we were looking a little bit at the atmosphere but mostly we were looking at planets from the shuttle. In particular we were trying to image Jupiter, and get the signature actually of the torus. That worked pretty well. That was a good mission. We were up seven times—seven shuttle missions. The last one was in ’98. We flew all our instrumentation—we flew two telescopes and the GLO [Arizona Airglow] Instrument. And we flew John Glenn.

That was the last mission because other things were going on that kind of precluded us looking at the ultraviolet on planets. The Galileo mission was approaching Jupiter, so they were going to take over from anything we had figured out. We would be in the Goddard Spacecraft Center just outside of Washington, in what we called POCC, Payload Operations Control Center. Once the shuttle got up, they would open the bay doors and they would start it up. We had ground control of the instrument. The only thing the astronauts did for us was to turn the power on, up until they closed the doors. The last two or three flights, we actually had three instruments up at the same time, the GLO, the UVSTAR, and Starlight.

Martin Tomasko

The Galileo experience was quite interesting. I wanted to propose an entry probe instrument for Galileo much like the Pioneer Venus instrument that would enter Jupiter’s atmosphere. When they announced the opportunity for Galileo, they said it was going into the daytime side, and we could study sunlight and the deposition of solar energy and do the same kind of thing for Jupiter as we did for Venus.

While they were reviewing the proposals, they decided they were going to change the trajectory and it was actually going to go to the night side. So we didn’t get selected, because we were working in sunlight, not with thermal radiation. But then about six months later they changed, and decided they were going to go to the daylight side anyway. So we were invited to submit the modifications of our proposal.

We submitted the modification and they said it had high scientific merit, and was really great, and they invited me to give a pitch to other co-investigators that they’d selected six months earlier for the mission. I gave my pitch, told them about my instrument, how big it would be and what it would measure. They asked the other investigators who thought this was a good instrument. They all raised their hands. Then the guy said, “Maybe I didn’t put that question quite right. We’ve already selected these guys and we’ve parceled out all the money. Who thinks that this instrument is so good that they’re willing to resign, get kicked off, so we can have room for Tomasko to fly his instrument?”

I was really annoyed. I thought, “If that’s the ground rules, why did you bother inviting me to do all this work? I just worked for months on this new revision of this proposal, and then you tell me that the only way you can add me is if one of these guys, who’s been working just as hard on his instrument, has to volunteer to resign?” That’s a hopeless situation.

Of course I didn’t get selected, but a guy got selected who had a thermal radiation experiment, analogous to my solar radiation experiment. That guy, in the meantime, had died. His instrument was given to another guy from Wisconsin by the name of Larry Sromovsky. I knew Sromovsky pretty well, and Sromovsky invited me to be a part of his thermal experiment, and to help calibrate his instrument.

The Galileo launch was delayed substantially because of the accident with the astronauts, the fact that Challenger blew up, and so Galileo kept getting postponed and postponed and postponed, and I was able to work with Sromovsky to a fair extent to save this thermal experiment, which had some problems; to make it work for the Jupiter entry probe.

So that was an exciting time, too. That instrument was a very difficult instrument. It measured thermal radiation and returned one number, but it turned out that that instrument was sensitive to all kinds of things. It was sensitive to the electrical charge; it was sensitive to humidity; it was sensitive to temperature and pressure. The joke was, it was a complete weather station, but it only gave you one number back. Sromovsky worked very hard to improve that instrument, and actually got some useful data out of it, but it was really only because it had been delayed so long.

Richard Greenberg

The reason I got on the Galileo imaging team was because I made the case that the orbits and the spin of the satellites of Jupiter might play a role in determining what they look like, and that we might actually be able to use imaging to tell some things about how they rotated and stuff. I was the person on the team who understood dynamics. The other people who were interested in satellites were more geologists.

I had really brilliant students working with me. Randy Tufts was actually a student in Geosciences, but you know, no one cared. Greg Hoppa was a Planetary Sciences student. Paul Geissler was a former Planetary Sciences student. There were several other people who participated in the Europa stuff: Dave O’Brien, Terry Hurford. One other person who was important in all this was Alyssa Sarid. Alyssa was a Space Grant undergraduate intern who was assigned to work with me. She had some major breakthroughs in Europa work as well.

What was interesting was when the images came down the geologists used their expertise to try to interpret what they saw, to a large extent using qualitative analogies with the kinds of geological features that they were used to interpreting.

Our group had a much more quantitative approach. Randy Tufts brought expertise in geology, but we in general had a much more quantitative approach to interpreting the geology than most of the other team members, because I came from this orbital dynamics background.

What we looked at was the tides on Europa. Tides actually distort the shape of the body periodically. It causes heating—and that’s why there’s an ocean on Europa, because there’s enough heat to keep most of it melted—and it also, because it’s distorting abruptly the whole body, it stresses the ice on the surface so there’s cracks, and it also affects the rotation, and it affects the orbit. The tides are really important.

We were able to explain some very distinctive crack patterns on Europa in terms of the tides. In fact, our explanation of a certain kind of crack pattern called cycloids was the first evidence that really said, “There is liquid water there.” It was later corroborated by studies with a magnetometer that measured effects of Europa’s presence in Jupiter’s magnetic field and confirmed that there was a salty or conductive layer—a salty ocean. We just really were able to explain huge amounts of that. That was pretty exciting.

William Boynton

The Mars Observer mission was interesting in the sense that the instrument that I was the leader of—it was called the gamma ray spectrometer, but we weren’t building it. This was what’s called a facility instrument. For a facility instrument, NASA takes responsibility for building the instrument and the design, and the science team which I was leading was just responsible for running the instrument and collecting the data and publishing the results.

The people who were building the instrument, Lockheed-Martin—at that time it was just called Martin-Marietta, in Denver, but it’s the same group that’s building the Phoenix Lander. We got a good instrument out of it. Now, when that mission failed, NASA decided to—first they were thinking of just rebuilding the mission, rebuilding the Mars Observer Spacecraft. In the previous era—like in the Voyager days, or the Viking days—NASA always built two spacecraft, just with the idea that something might go wrong with one, and if you have two you’re better off.

Well, in this case NASA was trying to save money, so they built all of the parts for two spacecraft but they only built one spacecraft, with the idea that if something went wrong then, two years later, we could put all of these parts together and fly it again. In fact, that’s kind of what everybody was thinking would happen, and they had some plans for how to rebuild it.

Everyone thought that was going to happen but there was a new NASA administrator named Dan Goldin, and he came up with this idea of “faster, cheaper, better,” and he was saying, “Well, rather than sending one big spacecraft to Mars, let’s send three little ones and we can do that for a lot less money.”

Not many people believed him. I remember we had a big meeting on the subject of people who were involved in the Mars Observer mission, and virtually everybody thought what made sense was to rebuild the spacecraft as they originally intended and fly it to Mars two years later. In the end I have to give him a lot of credit, because in the past we were going to Mars once every ten or twenty years, and with this new plan, for a while we were actually sending two spacecraft to Mars at every opportunity, and we’ve now gone back to just one. But you actually can do a lot with several little spacecrafts, and one of the big advantages was that you can learn something on one mission and then have a chance, four years later, to take what you’ve learned and build some new instruments to sort of capitalize on questions that might have come up with the earlier mission. So that worked out pretty well.

I actually remember when the Mars Observer mission failed. The spacecraft just stopped communicating. It went into a maneuver, it was going to do a certain observation, and it never came back.

For a while people were thinking, well, it has different safe modes that it’ll go into, and eventually it will figure out what’s wrong and it will start talking back to Earth. Those kinds of things happen. People were used to the idea that sometimes spacecraft have problems, and very often can figure out what’s wrong for themselves, maybe with some help from the ground, but they at least can reestablish communication.

For two or three days we kept hoping it would phone home. But it never did. I suspect it’s like when somebody is missing in action in a war, and you never really know if they’re dead or if they’re going to be found. It was one of these things that, after a while we finally had to realize this thing’s not coming back.

We had planned a big celebration here for after we arrived, and we had already arranged for the catering service and everything, and I remember Gene Levy, who was the Department Head, said, “Well, I guess maybe we ought to cancel that party.”

I said, “Well, how about if we do this?” I realized a lot of the people in the Department were, you know, kind of nervous and didn’t really know what to say to me if they saw me. Some would say, “I’m so sorry, Bill,” and some really wouldn’t know what to say, and some people would wonder what happened.

I said, “Why don’t we actually have an event where I’ll spend a half hour to an hour talking about the mission and what it was supposed to do, and what we know or don’t know about why it failed.” There are some upbeat things too, in the fact that one of the reasons we do these missions is to train new students and scientists and engineers, and that happened. Those people are still going out into the field even though the data doesn’t come back, people who were involved in building the instruments and calibrating them and building the spacecraft—they’ve all learned, and helped develop that technology.

So we did that, and it was kind of like a wake. I think it worked out very well, and people got to understand what was going on, and we kind of got to the point where we could say, “We’ve actually buried this dead spacecraft and now we’ll go on with the next mission.”

Fortunately I had another mission in the wings so I could work on that and didn’t have to spend all my time moping around. But these missions do take a lot of time, and you go some years without very many publications betting on the outcome, that you’ll get these wonderful data back that’ll make up for three or four lean years without very much in the way of publications. Having two in a row that failed, and another one, the [NEAR-Shoemaker] comet penetrator, that was cancelled, it was looking pretty bad. But fortunately Mars Odyssey came through and just made up for it.

William Boynton

For the NEAR Shoemaker mission—NEAR stood for Near Earth Asteroid Rendezvous—I didn’t build the instrument, but we worked with the John Hopkins Applied Physics Lab. So it was APL rather than JPL. They actually built a very nice spacecraft and when the mission was all over, they decided rather than just abandoning the spacecraft they would actually let it touch down on the surface of the asteroid even though it wasn’t really designed to do this. But there was so little gravity on the asteroid, which is kind of a small body, that they got away with doing this.

Dan Goldin, the head of NASA, was actually very nervous and didn’t want to say that they were landing for fear the public would get their hopes up too much, but they went ahead with it and it was very successful.

After they landed they weren’t sure really what to do, but they landed with enough sunlight that they could keep the solar panels in light where the spacecraft could work for a while. The evening that we found out that we had a successful landing, I said, “Hey, can we turn on the gamma ray spectrometer? Because we’ll get much better data being right on the surface than being well up in orbit, pretty far away from it.”

We had a meeting the next morning and everybody said, “Yeah, it’s worth a try, let’s try it.” So they turned the instrument on and in fact we got much better data back from being on the surface than we had in orbit. 

Peter Smith

In the midst of building the instrument for the Huygens probe, it became possible to propose for the next mission to Mars. There hadn’t been one in twenty years. I had a dream about transforming our Titan camera into a Mars camera. I sketched out some ideas and equations, and did some drawings, and ended up proposing for Pathfinder. We won that. We did our proposal in two weeks.

That changed my whole life. I had started in a temporary position 15 years earlier and now I was a Principal Investigator of a six million dollar project. We needed to design and build a camera; I quickly hired 30 people. It was a very strange time for me. I had to grow into this new life very quickly.

Timothy Swindle

In some ways, that camera, I think, is what brought back the Mars program. Pathfinder got there over the Fourth of July in ’97, and the cover of Time magazine the week before had been the upcoming big celebration at Roswell, New Mexico: The 50th anniversary of the Roswell incident.

Suddenly, the pictures came back from Pathfinder. I remember sitting in the auditorium downstairs at the celebration for LPL employees, and I had the family with me. We hadn’t signed up for the food—we were going to eat elsewhere—so we just went and sat in the auditorium, and all of the sudden here come these pictures from the surface of Mars, just flashing across the screen. No commentary or anything, but real-time photos from the surface of Mars.

That was just so cool, and apparently other people thought so too, because while Roswell had been the big news the week before, as soon as those pictures hit you never heard anything more about Roswell. Pathfinder was the top of the news. If it had been a very successful spacecraft with instruments that had made a lot of good measurements, but no camera, that would not have been true. I have to say that I think that camera might have been the biggest success; the imager from Mars Pathfinder. 

Lonnie Hood

We had a new lunar mission called Lunar Prospector which was launched in 1998. There, finally, all that work that I’ve done on the Moon came back to be valuable again. I’ve been analyzing that since 1998.

I was one of seven scientists who were leading that mission primarily. Alan Binder was the primary person. I was involved with him over a period of ten years while he was trying to get something going to go back to the Moon. Usually he failed, but finally, very miraculously, he was able to get a Discovery mission for going to the Moon for a very low cost, only I think 60-something million dollars, which was a very tiny amount for a spacecraft.

It was a very successful mission overall. It was in orbit around the Moon for a year and a half. We’re still analyzing the data from that even now.

Alan Binder

We started Lunar Prospector as a private effort, outside of NASA. When I was working for Lockheed at the Johnson Space Science, several of us got together to try to do a lunar mission ourselves, since NASA had completely abandoned the Moon and was not interested in it.

We had many reasons for doing it. One of them was to show that you can do a mission commercially, even though ours wasn’t commercial. By commercial I mean very low cost, very reliable, and get good data. As Prospector proceeded—we got to the point of launch and it was successfully in orbit—I spent a lot of time going to Congress and other people, trying to say, “Look, we need a data purchasing program, we need to take these missions out of the hand of NASA.” 

My mission cost $65 million. Cassini cost I think two to three billion, and Galileo cost a billion. These are wonderful science missions, but the cost can be reduced by a factor of ten if you do it commercially. Everything NASA does cost ten times more than if you do it commercially. You know, 65 million dollars, that’s postage-stamp money.

If we are going to start to not only explore space but utilize space for the benefit of humanity, and utilize lunar resources for humanity and so on and so forth, it’s going to have to be done commercially. Therefore I applaud things like Spaceship 1, and a friend of mine who has bought the Kistler Rocket and built a space plane for commercial flights. These are the things that count.

I think the public can be engaged by the private sector. I had people calling me up asking if they could volunteer to work—sweep the floors, whatever. Of course they couldn’t because I was building the spacecraft at Lockheed. But there was that much of a connection between the public and what I was doing.

I did tours of the spacecraft as we were building it. I was Mission Director, and it only took two of us to run Prospector. It was a straightforward, simple spacecraft, which was my message. That’s the way I believe things should be done. I had people come in when I was doing orbital maintenance burns with the spacecraft, and they were thrilled. They could sit there and watch us running a spacecraft.

Bill Sandel

I’ve been spending most of my time since 1996—wow, ten years now—on a mission called IMAGE [Imager for Magnetopause-to-Aurora Global Exploration], which is another Earth-orbiting mission. IMAGE is a MIDEX mission, mid-sized explorer missions. IMAGE was the first one; it was a new concept. Jim Burch at Southwest Research Institute in San Antonio is the mission’s Principal Investigator. The satellite and all the instruments on it are dedicated toward imaging the Earth’s magnetosphere in several different ways. It was a new concept, never been done before, so we’re in a position to really make some exciting new discoveries. And we did. It’s really been fun.

Our understanding has increased in big steps with each new mission. When you look with new eyes, you see new things. You can hardly avoid it. With IMAGE, boy, just coming to work everyday has been a real gift, because the plasmasphere changes all the time. It’s continually shrinking and expanding in response to forces from the outside, so you never know what it’s going to look like the next time you look.