Preflight Interview: John Grunsfeld

John, before we get into the details of the mission you're about to fly, we want to talk for a moment or two about you and how you got to this point. Why did you want to be an astronaut? Where does [the] desire to fly in space, to be an explorer [come from]?

Well, it really goes back, I suppose, to my birthday. I was born in 1958, the same year that NASA was born, and it was kind of synchronicity of a number of events in my childhood. As I was growing up, television was available in American homes for the very first time, and I distinctly remember seeing very fuzzy images on a black and white television of the very first space launches. It was also a very impressionable time for me, and I got to see, in National Geographic, the Mercury and Gemini astronauts and also, at the same time, pictures of mountains and people-especially Americans-climbing some of these very high mountains in the Himalayas for the first time. So I became enamored with exploration, and it didn't matter whether it was in the remote mountains or to space. I remember seeing the first moon launches, and that was on a color television, something quite astounding. So I decided [that] what I wanted to do with my life was to go explore, and as I grew older I became interested in science. Those two mesh very well, space exploration and science.

Are there particular people or one big event that you can look back at and say that that's the thing that really set my mind to it?

The biggest event in my life that I think would be called pivotal is in the third grade when my teacher was asking us to write biographies, and this was the first biography I'd ever had to write. I was prone to draw pictures of spaceships in the edges of my reports and things like that. But it turns out that when she was assigning these she would give somebody in the first row George Washington and Abraham Lincoln, Babe Ruth. She got to me, and she said, "John, I'd like you to write about Enrico Fermi." I'd never heard of Enrico Fermi, and my little heart sank. I went home and started reading about Enrico Fermi. He was a famous Italian-American physicist, and that got me very interested in physics and the life of a physicist, Enrico Fermi in particular because he was an explorer. He was a physics theorist, also an experimentalist. He was involved in the Manhattan Project, and he loved to climb mountains and loved to go out and explore with his family. So I found that his lifestyle was one that I wanted to emulate even back in the third grade.

From a third grader who becomes enamored of Enrico Fermi, how did you proceed and what steps did you take leading up to becoming an astronaut?

I was always a very curious little boy and loved to disappear in museums, much to my mom's chagrin, and find out what was there, learn about things. As I grew older, my curiosity grew. I stayed with science, always loved science, initially in geology and paleontology, looking for fossils. On the south side of Chicago, where I grew up, they would bring limestone from Indiana and I'd go and chop out fossils and kind of look back at the Earth's history. As I grew older, I became more and more interested in astronomy, especially when we moved out of the city and I realized that there were stars in the sky. [I] fell in love with stars and astronomy, went on to study physics in university, got my doctorate, and went up to the mountain tops and observed through telescopes and used NASA's satellites to do astronomy.

For an astronomer, then, it must be particularly special to be assigned to a mission such as you are right now, a mission being pulled together on relatively short notice, in NASA terms, for an early servicing visit to the Hubble Space Telescope. Summarize for us, first, what your role in this crew is going to be, and second, what it is like for you to be a part of this particular shuttle flight.

On STS-103 my designation is EV2, and "EV" means extravehicular. That means I'll be doing a spacewalk. The "2" is just because I'm paired up with Steve, who's EV1. We're doing the first spacewalks. So I'm one of the spacewalkers. I get to go out and work on the Hubble Space Telescope, which, for me as an astronomer, is absolutely a lifelong dream, and, I think, would be for any astronomer. It's a wonderful telescope, and astronomers love telescopes. We'll be doing two spacewalks, and then, of course, Mike and Claude will do two. We're going out doing kind of a maintenance mission on the telescope. While we were training for this mission, one day it suddenly dawned on me that, by going to the Hubble Space Telescope and the training that we were doing, in fact, I'd been training for this mission nearly all my life. I started studying astronomy and physics at MIT, learning how to build hardware and to work on telescopes, and all of those skills of electronics, working with connectors, how to design tools. [I went] on to University of Chicago, where Hubble got his Ph.D., continued to build telescopes, essentially, to fly in space, and then on to Caltech, which is where Edwin Hubble went after he got his doctorate at Chicago. [I went] up to the Palomar Observatory and [worked] on the instruments there and [observed] on the telescopes, which is where Hubble did a lot of his work. It suddenly came to me that this is a mission that I'd been training for nearly all my life, and that I was finally getting to do [it]. Absolutely a dream come true, [I] couldn't imagine anything more fulfilling for an astronomer, but also for me personally, the path that I took to get here, than being on this Hubble mission.

When you were assigned to this mission more than a year ago, you expected that you were going to have two years to prepare for a mission that was going to include six spacewalks. Earlier this year, you found out that you were going early and that you'd be performing an altered schedule of repairs. Tell us how you got the news about the change and how it's made a difference for you and your crewmates as you've gone about your preparation.

We actually knew about the problems with the gyros as we were training for the HST-3 mission, the full servicing mission, and so we knew that there was some possibility that we might go early to fix the gyros. Of course, you always want to fly as soon as you can. On the other hand, for the Hubble missions, it's a very valuable telescope. You want to make sure that you're fully trained before you go, so there was a little bit of hesitation in wishing for an earlier mission. We were all kind of on the edge of our seats really, last January, waiting for management to make the decision as to whether we would go this October or not. Once they made the decision, of course, we were all highly stimulated to get to the hard work of concentrating on this mission.

To help us set the stage for understanding the work you and your crewmates are going to do when you go, let's talk for a moment about the mission of Hubble itself. What is it that the Hubble Space Telescope does, or can do, that telescopes on the ground, and even other telescopes in orbit, can't do?

The Hubble Space Telescope is really great at a couple of things. First of all, it has a large mirror. By terrestrial standards it's not a particularly large mirror anymore, but it still has a very good light-gathering power. You need a lot of light-gathering power to look at things that are very distant, or very dim, or things that you want to look [at] in great detail. Hubble's true strength is in two particular areas, one of which is its ability to point very accurately in space at a single object. That pointing is important because you don't want a little bit of jitter in your pointing to smear an object out, if you want to look at great detail. The other thing that Hubble is very good at is going back to the same [point] in space time and time again. If you want to observe something several times that might be changing, even over periods of days or weeks, you have to be able to go back to that spot. There are two elements of the hardware in the telescope that allow you to do that, one of which is the gyros and the other of which is the Fine Guidance Sensor. The gyros allow you to point very stably. The Fine Guidance Sensors allow you to come back to that same spot time and time again. So on this mission, we're working on both of those components. What we're doing on this HST 3A mission is really to go and preserve the extraordinary capability of Hubble.

Let me get you to expand on the point. As you mentioned before, the gyroscopes are responsible for it being able to point precisely. It's the failure of gyroscopes that's really prompted this mission to be going sooner than planned. Explain why we have to go and service this telescope now.

Well, the Hubble is capable of carrying six gyroscopes, two in each of three packages. We call them RSU 1, 2 and 3, Rate Sensor Units. Right now Hubble only has three working gyros, and you need three to be able to do the pointing. So if another gyro were to fail, Hubble would be unable to do science. It's not in any danger, but it would be unable to do science. Of course, it's very expensive to operate an observatory, and many students and postdoctoral researchers and professors are depending on this research for their livelihood. There are lots of questions we're trying to answer, and if Hubble were to be inoperable to do science for a period of months or longer, that would be very damaging to international science. So what we're doing in this mission is going up to do what's essentially a maintenance activity, and it's preventive maintenance to make sure the telescope continues to do good science. The gyros are known to fail. It's a reusable component, in the sense that you go up, you take one down, you refurbish and put it back up. That was planned from the very beginning. The schedule would've been better if there were four gyros operating right now and we had our leisure to go up there and fix it, but right now we're going up to ensure that there's no disruption in service.

The science that's being gathered, as you made reference, is quite important to astronomers and other scientists. Can you characterize for the layman, who's not an astronomer, the value of the images and the data that Hubble has gathered up to this point and presumably will continue to gather in the years to come, once you've finished your job?

Well, let me talk about the relevance of Hubble right now in a kind of broader perspective. Hubble itself takes tremendous images. It can point at one spot in the sky for a very long time. That allows us to look very deep into the universe, and looking deep into the universe is essentially looking back in time. So one of the biggest opportunities we have with the Hubble Space Telescope is to look back in time, to do, essentially, archeology of the universe. What was the universe like in the very first points at which stars and galaxies were forming. And we can see back almost all the way to the edge of the universe, fourteen billion years. That's the cosmological perspective, but more locally, in terms of now, we have the Compton Gamma Ray Observatory in orbit. We have a number of extraordinary telescopes on the ground-the Keck I and Keck II telescopes in Hawaii, which are NASA telescopes-as well as telescopes all around the world. [There's] the Rossi observatory, which is an x-ray observatory in space, and all of these work together. For an example, the Rossi observatory observed a gamma ray burst, and along with BeppoSAX, an Italian observatory, we found out where it came from. Gamma ray bursts are this tremendous output of energy from the sky, and we have had no clue previously where it came from. The Compton observatory was going to try and answer that question and only tantalized our quest for what they were. In combination with all of these observatories, we were able to take the x-ray data from some satellites, steer the Hubble to look in that region of the sky, in combination with some ground telescopes, and find out that the gamma ray bursts are actually coming from far outside our galaxy. What that means is these things that we thought were sort of galactic burps of gamma rays, high energy x-rays, are actually spectacular events that are second only to the Big Bang itself in the amount of energy that's released. So all these telescopes working together-and Hubble was one of the really crucial resources for us to find out what these enigmatic sources are- have allowed us to solve a puzzle that's been with us since the early 1960s, when we put up the first satellites.

To permit Hubble to continue to do that work, you and six crewmates are about to go grab it out of orbit and secure it to a rotating table in Discovery's payload bay. Talk us through the procedures of that rendezvous with, and the grappling and berthing of, Hubble, and particularly, tell me about what you will be doing as part of the team on that day.

Well, of course, my prime role with Steve, Claude, and Mike is to support the EVA activities. So prior to the rendezvous we're going to be getting our spacesuits ready, and that's just to cover the contingency that, for some reason, we can't put Hubble into the payload bay. Once we're there, Steve and I can go out and manually put Hubble into the payload bay or close the latches that will put Hubble into the payload bay. Once we have that activity done, while Curt, Scott, and Jean-François are working the rendezvous activity, I'll go up to the flight deck. On this flight, I'm one of the computer guys. I'll be putting the network together of laptop computers on which we run some programs that help us with the rendezvous. We'll have all of that assembled on the flight deck, and I'll work in a support role. As we get closer to the telescope, I'll maintain all the computers. When we're within a few thousand feet, I'll actually take a small handheld laser, just like the speed-gun lasers that police use to catch you for speeding, and aim it at the telescope and help to give ranging measurements. I won't use it for the speed as much as [for] how far away we are from Hubble. It's just one of the things that we commonly do. I did that for the Mir space station rendezvous we did on my last flight, and we'll do that for Hubble. And, of course, take lots of pictures.

The next day, with Hubble successfully grappled and berthed, you and Steve Smith are to exit the airlock and start a series of spacewalks that are designed to keep Hubble in shape to do its job, including the replacement of the failed and ailing gyroscopes. Talk us through the timeline for your first spacewalk, and explain what you'll be doing as you perform the tasks on your several hours outside in the payload bay.

Well, of course, as you mentioned, the first thing Steve and I do is depress the airlock. That means to let all the air out of the airlock, and that'll be a slightly time-consuming process to make sure that we don't cause any disturbances in the solar arrays. Steve will open the hatch, [and] go out and start cleaning the payload bay, so to speak, getting it ready for our EVAs. I'll bring out a board that's covered with tools and mount it onto the shuttle's robotic arm. I'll go out and climb onto that arm and we'll get to work on the very first task, which is the highest priority task, changing out those gyroscopes. And it's a very delicate task that we're going to do. We'll go back to the telescope, which is in the back part of the shuttle and open some large doors, and I will physically put Steve, initially, in the bottom of the telescope where the gyros live. And this is a very sensitive area. We have large star tracker shades that we're not allowed to touch. We have the axial scientific instrument bay, which has hundred-million-dollar science instruments. [These] are, of course, what Hubble uses to do its observing, [and] we're not allowed to touch [them]. So I'll delicately put Steve into the telescope, and then we'll, with very careful choreography, remove the old gyroscopes and put in the new ones. Steve is going to do two of them, then I'll take him out of the telescope and I'm going in, on the robotic arm on my back, so to speak, and replace the center one, RSU #1 again, touching nothing other than the gyroscope. So we've been told, once we're in the telescope, to be a statue and not touch anything other than the gyroscopes. It's a very delicate activity for something that was planned to be somewhat routine. After that we are going to close those doors and put in something called Voltage Improvement Kits, and essentially this is because of some battery-charging problems that they've encountered. We're going to improve the ability of Hubble to use all of its solar power for doing science. And while Steve's doing those-we'll swap so that he's on the robotic arm of the shuttle doing the Voltage Improvement Kits, or the VIKs, as we call 'em-I'll actually go around to the back side of the telescope with some small pieces of white blanket and put [them] on handrails on the back of the telescope where, the next day, Claude and Mike will be working. That's because, frankly, Hubble has been in orbit for nine years, coming up on its tenth birthday in orbit, and some of the paint is starting to look a little shaky. So to protect the telescope from any flakes of paint that they might knock loose, I'm going to put covers on the handrails that they use, and so I'll be back there free-floating for about an hour.

The day after you and Steve complete those tasks, scheduled to be Flight Day 5, you two stay inside while Mike Foale and Claude Nicollier take their turn as spacewalkers. Describe the part that you will be playing while the other pair are outside doing their jobs.

Well, after the first EVA, I'm sure I'm gonna be floating around the cabin a little bit more lightly and probably a little bit tired. My role is to back up Steve as the inside crewmember directing the EVA and also as the second arm operator. So Jean-François and I will swap off tasks flying Mike and Claude, alternately, around the telescope as they do their work, changing out the computer and then the Fine Guidance Sensor. Handling the robotic arm is a very exciting task, especially when there's a person and a hundred-million-dollar instrument on the end of it, with the backdrop, of course, of the Hubble Space Telescope. So that's something I'm very much looking forward to. It'll be my first opportunity to fly the robotic arm.

You describe that as exciting and, for those who've never even been in space, just to be there would be exciting. Can you give me some sense of what doing this task adds to the thrill you're going to have from being there?

I'm a private pilot, and I love flying. When you're operating the robotic arm, it's very much like a flying task. Of course, it has a little bit of a heightened sensitivity, as does flying a real airplane, because you're working very close to a telescope, and it's critically important that we don't knock the robotic arm into the telescope, to be blunt. It's a very delicate machine, and we have to be very careful. You'll see us in our choreography and the talk back and forth from inside and outside the cockpit as we talk about how many inches or how many feet we are away from various parts of the telescope. But basically it's a flying task. You're controlling the robotic arm with a person on the end of it, and it's also exciting because the person who's driving the arm, the arm operator, and the EV crewmember, the spacewalking crewmember who's on the arm, become a very tight pair. You, as an arm operator, have to put your head out on the end of the arm with that crewmember so that you can operate and give them what they need to do their job.

Have you all, the whole group of you, developed a special way to talk to one another to improve that coordination?

We have a very tight protocol of what you're supposed to say at various points so that if somebody says "take me out," you know precisely what that motion is when you're operating the arm, and "up" and "down." If you're operating in the payload bay you might say "take me forward," "take me aft," starboard, port-we use the navy terms. When we're close to the telescope, we talk in telescope coordinates with respect to our body: "take me in" means to take me into the telescope. You know, sometimes you want to say to the robotic arm operator, "beam me up," but you just say "up."

You and Steve Smith are slated for a second spacewalk on Flight Day 6. Again, tell us what is planned for this spacewalk and what your tasks will be as part of that pair.

The second EVA that I'll do, which is on our third spacewalk of the mission, I'll come out, and again I'll start on the robotic arm. There are three main tasks that I have that are all very hand-intensive, so I've been doing a lot of arm training to strengthen my forearms. In the spacesuit, you're like the Michelin Man. It's inflated, and there's a vacuum outside. Every time you close your hands, you have to work against the suit, so it's a very tiring thing just to move your hands. I'm going to start out and do something called the Optical Control Electronics Improvement Kit, but basically when we change the Fine Guidance Sensor-which is what Mike and Claude will do on Day 2-we also have to make a small change to some connectors on some electronics. So the very first thing that you'll see Steve and myself do is go around to the back side of the telescope, open a small door, and change some connectors, and that'll take about half an hour. After that we'll go to the front side of the telescope, open up another door, and inside are two boxes. One's called the S-band Single Access Transmitter, and the other is the tape recorder. And we're going to change those boxes out. The transmitter has failed, and the tape recorder, we're going to replace with solid state memory. The interesting thing about the transmitter is that it was never intended to be changed out on orbit. It was a box that the engineers said, "This will never fail." Now there are two of them, so Hubble is still transmitting good science and engineering data over the working one. But the one that failed, [it's] sort of a mystery why it failed, and we're gonna find out once we get it down to the ground. They do have a backup and I'll be replacing that. Since it was not designed to be removed on orbit, it has tiny little connectors. In fact, their name is very descriptive. It's called a sub-miniature assembly connector, SMA, so it's very tiny. It's the kind of thing that they use in little GPS receivers or cell phones. So my task, in these huge gloves, is to remove these connectors, remove some screws that are non-captive, meaning if I let go of it accidentally it'll float off (we have special tools to do that), and then exchange this box for a new one and re-connect these tiny connectors. So that's something I've been practicing a lot. Changing out the tape recorder for the solid state memory is something Steve did on his last mission, so he's kind enough to let me do that on this mission. That's a very straightforward task and one that will enhance the ability of the telescope to store data on orbit.

And all of this will take up how much time for your second spacewalk?

[We] should be able to do that in a little under three hours. In the water runs that we've been doing, we've been successful in replicating that several times, and that's going to be very close choreography between Steve and myself. I'll be on the robotic arm for doing this transmitter task with the tiny connectors, and Steve will be free-floating, holding on to the stanchion, which holds all the tools. I'll feel like a surgeon because I'll say, "Hand me the pistol grip tool," which is an electronic drill. He'll hand me that, and I'll drive the bolts and hand it back to him. I'll ask for another tool, and he'll put it in my hand, a connector tool. I'll remove the connectors. It's something that Steve and I have spent a lot of time discussing, all the intricacies of each tether and each tool, so that it goes as smoothly as possible. Of course, while I'm working, Steve will have a tremendous view, and he'll also go down to retrieve the new one when I have the old one off. We'll do a swap, and he'll free-float back down. So he'll be going up and down the telescope quite a lot during that activity.

There is a fourth spacewalk on the mission planned, that one also for Mike Foale and Claude Nicollier, after which-all spacewalks complete and the planned improvements to Hubble made-it'll be time to send it back out on its mission. Talk us through plans for deploy day, when you take Hubble off of its platform and send it back out to work.

The deploy day is, I think, going to be kind of a mixed day because we'll have spent the last four days inside the telescope, scurrying around on the outside of the telescope, doing all these repairs, and then you have to say good-bye to something that we will have spent almost a year training to do and then actually living with the telescope. It's going to be a very busy day. We have to deactivate some of the systems where the shuttle is providing power to the telescope. We have to reset all of our computers on board to get ready for the rendezvous. Then, at the appropriate time, Jean-François will grab the telescope again with the robotic arm. We'll open some latches that are holding Hubble in the payload bay. He'll lift it up over the shuttle, and then it gets very exciting because he will, with concurrence from the ground, let go of the telescope [and] move the arm away, at which point the shuttle and the Hubble Space Telescope are kind of in formation flight, orbiting the Earth. At [that] point, Curt will do some jet firings to cause the shuttle to go underneath Hubble. The reason this is so exciting is we have large windows that we look through on the top of the space shuttle, and Hubble will pass just right over our heads. It will be very exciting to look up and see Hubble passing by, not quite inches but feet from the orbiter. Then, we'll say good-bye, take a lot of pictures, and slowly back away.

After that you all prepare to come home.

The camping trip is over. It's time to pack everything up, and we'll have a lot of stuff out, a lot of tools for the Hubble Space Telescope, many specialized tools. So we'll have to pack all those tools up, put them all away, get our entry suits out from storage, put all the seats away, and a day-and-a-half later or so come home.

A landing planned at the Kennedy Space Center will conclude a mission that was planned, prepared, and executed in a relatively short period of time, that will really "keep" the Hubble Space Telescope going on the mission that it's been on nearly ten years. When you're asked about this, how do you explain how the mission, that you and your crewmates will fly and that hundreds of other people will support on the ground, is furthering the objectives of space exploration?

The Hubble Space Telescope itself is an exploration tool, and it's not just, what some people think, to look at stars. We're looking deep into the universe. We're learning about where we've come from as far as the universe, but it's also used more locally. When we had the Mars Pathfinder landing on Mars, we used the Hubble Space Telescope to determine the weather on the surface of Mars day after day, as we were getting close, to make sure that it was safe for the Pathfinder to land, that it wasn't going to land in a windstorm. We've looked at weather on the moons of Jupiter, and [on] Jupiter. When Levy Shoemaker, the comet, went into Jupiter's atmosphere, we were able to use Hubble to track that. So we're actually doing solar system exploration with the Hubble Space Telescope, and, of course, everything in between. We've spent a lot of time looking at stars that are just like our sun that, near the end of their life, have exploded into fantastic nebulae, planetary nebulae, with amazing pictures. You would think that it was an artist's work with an airbrush, these things are so beautiful. So we're learning about our backyard, our universe, if you will, with the Hubble Space Telescope. In a totally different sense, though, Hubble has taught us how to service things in space, and that's something very important. When you build something on planet Earth- a car-you hope that it goes these days, as the advertisements say, a hundred-thousand miles between tune-ups. Well, of course, with the Hubble Space Telescope, between servicing missions it's hundreds of millions of miles, but, nevertheless, things do break. In a certain sense, it's important to take that into account and to learn how to fix them. On the Mir space station, we had example after example, and of course Mike Foale lived that and I saw that when I was up there. You have to know how to fix things in space, not just inside but outside. If you try and design something to last forever, it won't, if it has any moving parts or electronic parts, and all spacecraft do. So I think what we're really learning with the Hubble missions is how to execute finely crafted activities on very complex machinery and very delicate machinery. I'm convinced that when we go to the moon, and I hope it's soon, that astronomy will be one of the first things that we go there to do long-term. When we set up bases in Antarctica, it took a very short time before astronomers realized that, for six months of the year, it's dark there, and it's a wonderful place to do astronomy. You don't have to cool the detectors. It's already cold. The sky's very dark, very clear, very dry, so astronomy played a big role in the exploration of Antarctica. There's a huge presence there now. The moon is an even better place to do astronomy, and when we go there, we're going to have to know how to repair the telescopes, what kind of tools, techniques, and spacesuits you need, and Hubble has pioneered that. So I feel like, on this mission, as well as the previous servicing missions and in the future ones, we're going to continue to generate lessons learned that we'll use as we go out into space to do astronomy or to explore Mars or wherever we might be going.