NASA - National Aeronautics and Space Administration

STS-125 Commander Scott D. Altman. Photo Credit: NASA

Q: Of all the careers in all the world that a person could aspire to, you end up a professional space traveler. So what was it that motivated you, or inspired you, to become an astronaut?

A: You know I started off at 3 years old wanting to be a pilot, to fly. Something in me connected with that idea of leaving the Earth and flying around, and ever since then, as I got older and older, I’ve tried to pursue that dream. You know, I went to fly airplanes with the Navy, then become a test pilot and fly a little faster and a little higher, and that brought me on a field trip here to NASA where I realized two things: one, astronauts are, in fact, real people who come from different backgrounds; and then the second thing was, a lot of them had a background like I did flying military airplanes, working as a test pilot. And looking at what was going on here, it was clear to me this was the place I wanted to be to fly higher and faster — obviously NASA’s going the highest and fastest — and it also touched that heart of exploration, to be able to look outside and wonder what’s up there and then, hey, let’s go find out. That’s just an incredible feeling. I’m so fortunate to wind up there.

Let me ask you a bit about your background, starting with your hometown: Tell us about the place where you grew up.

Well, I grew up in a relatively small town in central Illinois, the heartland, I think, Pekin, Ill. I also had family members who owned farms in northern Illinois. So I spent my youth growing up between the small town and the farmland driving tractors around. It really was to me an idyllic combination of those things and I enjoyed it a lot. My parents were both schoolteachers, they focused on education, but when I told them when I was 3 I wanted to be a pilot they said, "You can do whatever you put your mind to, if you work hard and keep after it." And, while there were bumps along the way, I’ve always held that in me and they’ve been an inspiration to me.

You told them when you were 3 that you wanted to be a pilot?

I said, “I want to be a pilot.” Yeah, they kind of laughed, and they said, well, let’s finish toilet training first, but they used that to motivate me to get through that, as a matter of fact.

Do you get a chance to, to pick out Pekin from orbit?

My very first flight, we were in an orbit that took us over the U.S. during daylight passes so that was awesome, and I would keep looking out the window to find my hometown, and every time we came over there were clouds and I missed it. Then, the last day before we de-orbited, I looked ahead and there was a pass that was coming close, I thought, well, this’ll probably not work but I’ll give it another shot. And as I went up to the flight deck I saw we were going over St. Louis and I looked down and there it was: I could see the city, and from St. Louis you follow the Illinois River up and it took me right to Pekin, Ill., and it was there. I couldn’t believe my eyes. So I grabbed the camera as fast as I could, I was kind of shaking, taking pictures; it was just an incredible feeling to connect from there back to the beginning where I grew up and be able to take a picture of it. That means more to me than a lot of the memories I have.

Do you, you feel like that place and those people there helped make you the person you are today?

I do think a lot of the things that I based my career, how to deal with people, how to understand what’s going on, came from starting off back there in that area. The value of hard work, dedication to a goal, an ideal, and following that, have been things that I picked up right there and have just carried with me. I think you look back you never really see a clear path from where you were to where you are now. But then you see those little things that have been a key part of getting you there, and I’m just thankful it all worked out the way it did.

Help me fill in the space between Pekin and here: Give me the thumbnail sketch of your education and your professional background?

Well when I was in high school wanting to be a pilot I applied to the Air Force Academy and actually got a congressman to give me an appointment. "But when I took the physical they measured my sitting height and they said, "I’m sorry, you’re too tall to come to the Air Force Academy as a pilot; you could come as a, a weapons officer or something like that." But I wanted to fly. So I said, well, I’m sorry I’ll have to do it a different way. I was crushed, at the time, but I went to school at the University of Illinois studying aeronautical engineering because I said if I can’t fly aircraft I’ll learn about them and maybe design them. And the Navy sent me a flyer about nuke power and I sent that back saying no, I’m not interested in going nuclear, but send me some pictures of airplanes, because really, growing up, I only thought about the Air Force for airplanes and not the Navy — middle of the country, not many oceans around to see aircraft carriers.

Navy is boats.

Exactly. So they sent me back a brochure about Naval aviation, and as I’m flipping through it I see that the height requirements are different, and I’m short enough to fit in Navy airplanes. So I called the recruiter up and signed up and then got into the Navy that way. I flew F-14s out of Miramar [Naval Air Station] in my career, then went to test pilot school on the East Coast, and back to San Diego after that, and then here.

Now we know flying in space can be dangerous. Scott, what is it that you think, all of us, get as a result of flying people in space that makes this risk one you’re willing to take?

You know, there are many ways to answer that question. One of them is the technology, pushing ourselves to do more, always ends up with capabilities that we don’t foresee when we’re beginning. The second is understanding the way our universe works in that basic kind of research also produces results that you can’t foresee. I don’t know if people understood how quantum mechanics would ultimately impact our ability to have the high-speed computers that we have today and understand how all that works. So there’s that. And then, I think, just in everybody’s heart, there’s an interest in looking over the next hill, you know, from the top of that mountain, and looking out at this universe and trying to experience what’s out there. I think humans traveling there benefits all of us because you can say, "yeah, we are out there, as a group." And then the Hubble does the same thing: We can’t travel 13½ billion light-years, but when Hubble brings that to us, it’s like we’re there. So it’s a joint effort to be able to travel to the most distant reaches of the galaxies.

We can’t travel that far yet.

Hopefully, one day we’ll be able to. When was the first time you ever heard of the Hubble Space Telescope?

Wow! I would say it was back in college. I was an aeronautical engineer. I was following along with the shuttle program, and somebody was talking also about a new telescope, and the whole idea to put one up above the atmosphere to get better pictures of all the cosmos, and I thought, well that’s a pretty neat idea. And I started looking at the pictures. Of course, I remembered the big “black eye” debate when it was first launched and the mirror appeared to be defective. We later found out it was ground to a slightly different specification, so I followed that and then kind of Hubble’s rebirth. But it wasn’t until my last mission that I got most acquainted with the Hubble.

What is it that the Hubble has meant to the science of astronomy in its mission so far?

It has really been an incredible tool. I’m fascinated by that, because Hubble really is cutting-edge science. We’ve made observations using the telescope that have reformed the way we understand how our universe is built -- the fact that things instead of slowing down as they get farther out, are actually accelerating. It’s kind of foreign to what I learned growing up in science class. And Hubble has done the science that made those observations, that analysis, possible. Yet at the same time, it’s an incredible platform that takes those pictures that take the average person out 13½ billion light-years away from where we sitting to give you those views.

What has Hubble meant to the field of human space exploration?

That’s a, another area where Hubble’s a great example of how people and robotics, basically instruments that are out there on their own doing their mission, can work together because if we had just purely launched a telescope it would have been defective and we wouldn’t get everything that we have. But because we built it for people to work with it, we can go visit it and improve it, make additions, fix things and take advantage of new technology. That’s the other thing: If it had been launched back in the ’80s it’d still have ’80s technologies; now we’re able to put new instruments in and increase its range.

There are a lot of people involved in getting you and your crew ready to fly this mission, and not just here in Houston. Talk about the training and the support you folks have gotten from the people behind the Hubble who are at the Goddard Space Flight Center and the Space Telescope Science Institute.

Those are the two prime places, Goddard for the technical side and then the Space Telescope Science Institute for operating the telescope, taking the observations. The neat thing about the Hubble missions is that you get to go to those places and talk to the experts, the people who are designing the instruments; this is how it works. You've got a question about how it installs? He says, "Well, we built it like this because of that, and he tells you the whole story. Like, oh, OK, that makes sense to me now; I understand where I have to be careful and where I can move things around a little bit. It’s just a phenomenal opportunity to get in touch, face-to-face, with the engineers, and see space hardware in person and touch it when you’re in the clean room.

It’s not any surprise that those people love the Hubble Space Telescope and the mission, but Hubble’s become something of an icon outside of the science community. Why do you think it seems to have touched so many people?

I think in the end it’s exploration, that that is something that connects with people. You know, I remember when I was a kid going outside and looking up at the stars and going, "Wow, I wonder what’s out there," and you watch science fiction on TV, which is really just people wondering what’s out there and coming up with ideas for what it is. Hubble is a tool that can take you out there to those distant galaxies, those pictures that come back. I wonder what’s out there. Hey, here’s a picture of something that’s out there; wow, that’s amazing. And I think it connects with people on a very visceral level. It’s amazing to me when I talk to people and I say, hey, I’m going to the Hubble, they go, “Wow, I’m so glad we’re going back.” All kinds of folks in every walk of life know about Hubble and connect with the idea that it’s a good thing for us to have and they’ve made some connection with it on their own.

What’s your favorite Hubble image?

You know there are so many great images; it’s easy to latch onto one or the other. My favorite is probably The Mice galaxies that came down after our last mission: a picture of two galaxies, you know, over a billion stars in each one, and they’re doing this, they’re moving towards each other and there’s a little animation of what’s happening that shows them doing this little dance around each other, eventually, until they merge into one galaxy. And just thinking about that being out there amazes me. Plus, in the background of that picture are some 1,500 other galaxies, each with a billion stars in them. You start thinking, this is a soda straw slice of the night sky with a number that’s huger than I can really comprehend of other galaxies with billions of stars in each one of them. And I’m saying, wow, this is a big place we live in.

You’re commander of this servicing mission to the Hubble Space Telescope. Scott, summarize the goals of the mission and what your main responsibilities will be.

Well, I’ll start with your last question. My main responsibility is, and as the commander, basically to make sure everybody else, is ready to do all the work, and I sit back and watch things go smoothly. If there are little bumps in the road, my job then is to coordinate that and make sure we do the best we can with what we have. What we want to do, though, is refurbish the Hubble so that it can operate as long as possible. We’re going to add some new instruments, that new technology into the telescope to extend its reach, and then we’re going to go in and kind of do internal surgery on some instruments that are already in the telescope. We don’t have enough room to take up a whole new version, so we’ve got to go in, pull boards out, and do the kind of repair you normally would be doing in a clean room somewhere and we’re going to try and do that in place on orbit.

This final servicing mission to the Hubble Space Telescope was actually cancelled after the loss of Columbia; it was deemed to be too risky for the crew to do. But that decision was reversed almost two years ago, here you are. What was your feeling about the decision that was made not to fly to Hubble, and then when that decision was overturned?

I think most of the astronauts were disappointed because Hubble is such a great blend of what people can do and the science that you get out of it; everybody loves demonstrating that capability to do work in space and get positive results out of it. I do understand the risk decision. That’s a tough one, and the people at the top have to make that call. It’s not a good idea to ask an astronaut all the time what’s too risky, because a lot of us will raise our hand to take chances for stuff we believe in, and to be able to fly. The whole concept of going somewhere where you don’t have a place to shelter, like the space station, was a little different. But after that people kept working on it. There was a robotic effort. We looked at how we could do the servicing, and people realized that was a big technological challenge to get that kind of stuff done. They came to the conclusion that if we work this correctly, we could come up with a plan that answers the mail on the risk question while still getting the work done on the Hubble, and I was thrilled when they decided to put the mission back on.

Your flight, like all shuttle flights now, will include a thorough inspection of the exterior of the orbiter using the Orbiter Boom Sensor System. Tell me about how that’s accomplished and what you’re looking for when you do that.

It really is a new capability that wasn’t on all three of the flights I had before. We launched and we assumed everything was going to be in good shape. So now we don’t have to assume: We’re going to look and inspect pretty much every inch of the orbiter for damage, so when we decide to re-enter there is an extremely high level of confidence that everything is as it was designed to be for entry. The boom has technology at the end of it, both with a camera and a laser system, to be able to tell how deep any impacts are so that as you scan over everything, especially the leading edge of the wing — that’s where the most of the heat load goes into the vehicle and that has very tight damage tolerance criteria, so we look at that very carefully — and then folks on the ground analyze all the data that we pump through and send back down and give us the go for coming back. Of course, the first part of that is getting rid of the debris that was falling off the tank causing the damage, so we’ve done a very thorough scrub, made design changes to the tank, so, eliminate the source of the problem, make sure that you can see if you have a problem, and then have a strategy for what to do if you find it. And I think we got all three legs of that in place.

We have tested out possible means of repairing a shuttle since Return to Flight. What could you fix if you found damage on Atlantis this time?

Well, clearly we have some capability to fix damage to the tile in different places, to go through and put a wash over that or some repair in place to give you some capability. There’s also some repair capability for the leading edge of the wings, the RCC [reinforced carbon-carbon], for some small cracks to go out and put something on there. Then you have to look at how confident are we in the repair versus entry and what you would do after that. So NASA’s been relatively conservative, not trying to bite off too much, but make sure we demonstrate the capability to return on whatever repair we did, that we were confident that that would work.

Well, unlike other shuttle flights, as you said a moment ago, you don’t have the option to go wait at the International Space Station for another ride if you can’t repair Atlantis so it can come home. So what are your options in terms of a rescue?

If we get to the case where we’ve had damage and we’ve either decided it’s not repairable or we’ve gone out and done a repair but people think, "Well, I’m not really sure; we don’t want to take the chance," we have an option that NASA has built into this mission and that’s a rescue vehicle to come to us. So we will shelter in place on our orbiter, power down to extend the oxygen supplies that we have, the CO2 removal systems, and we can go up to roughly 25 days waiting for somebody to come up to us. Meanwhile, NASA’s decided to have an orbiter on the pad so the day we launch, if we find damage flight day 2 or flight day 3, turn that mission on and by our flight day 7 or so, they’re airborne, coming up after us. They’ll rendezvous with us and eventually we’ll do an EVA, a spacewalk transfer, to get from our vehicle to the other one, and come home on that rescue vehicle.

The two shuttles would dock to one another?

The two shuttles would kind of rendezvous and since we don’t have a docking system, we’re going to use the arm and attach an arm from one to the other, and sort of fly close formation and then slide up and down the arm making the transfers of the crew between the two vehicles.

STS-125 Commander Scott D. Altman prepares for a flight in a NASA T-38 trainer jet at Ellington Field near NASA's Johnson Space Center, Houston. Photo Credit: NASA

And then have a packed other orbiter to come home in?

We’d have 11 folks on that, which is actually the plan right now for coming home from station. The only difference, really, is where you live for that period of time, and the fact that because we’re on our own vehicle we can’t wait too long: 25 days is about as long as we can make an orbiter last up there, so we have to have somebody come pretty quick and then be able to get down, but there’s margin in that, I think. It’s a very low probability of an event, but I’m glad that there’s a relatively robust plan to deal with it if it did happen.

All the work you guys are planning to do to get Hubble back up running at full steam is contingent on a successful rendezvous and grapple and berthing of the telescope. So tell me what part you, the commander, play in those operations, and describe how you and your crewmates go about getting that telescope out of the sky and putting it down on a work platform in the payload bay.

Rendezvousing with Hubble is a little different than going to space station. Obviously, it’s in a different orbit, but it’s also a small target compared to how big station has gotten, and it doesn’t help us out as much during the rendezvous in that station has a little system that gives it range and range rate as you get close; Hubble is just passive; it’s sitting there; it doesn’t have reflectors. So we’re using a little handheld laser, which is kind of like a police radar gun that you would see on the side of the road, to get the distance and the closing rate as we’re coming up to Hubble. We’re doing it basically by hand. And when we get into the final phase, I’m looking out the window, watching Hubble, and then listening to the calls that my other operators are making by using that laser range finder about how close we are and how fast we’re going to know what input to make as we get close to it. So I think it’s a more challenging rendezvous than having as much information as the station guys have. At one point last mission we talked about putting a reflector on Hubble to make it easier for the next guy, but I thought, well, you know, it was hard for me; let’s let it be as hard for the next guy. Now it turns out I am the next guy so I realize that was shortsighted of me.

Well, you will be the only one to do this who’s got experience at it. That approach doesn’t do the whole trick, though.

Great reminder because now, once we’ve gotten to where we’re in close formation with it, it’s not like station where you just fly on in and dock, use a docking system to mate everything up. I have to pause there, keeping everything in pretty close relative motion, and then my arm operator, Megan McArthur, is going to use the robotic arm to then reach up and grab the telescope and latch on to it, and then she’ll slowly move it into the back of the payload of the orbiter and we have a little mini-docking system that latches on to the telescope so she can let go of it with the arm and it’ll stay in place in the bay so we can do all five of our spacewalks.

So you’re, you still have a big part to play at that point because you have to keep Atlantis and Hubble, relative to one another, not moving?

Right. So if I’ve done my part well and flown up to Hubble gracefully, I can stop and I say, OK, I’m going to go to free drift, which means I’m not making any more inputs, and that we’ll stay close together without much motion to make it easier for her to reach out and grab it. We also train to grab it if it’s moving a little bit but my job is to make it as stable and easy as possible for the arm operator to go out and get.

After that berthing there’s time set aside in your timeline for a survey of Hubble. Tell me about that task and what are you guys looking for then?

Well, it’s going to have been more than six years since we visited Hubble, and one of the things they want to do right away is understand exactly what shape it’s in, so we’re going to look at it up and down, all around, to make sure nothing has happened. There is a micrometeorite environment in orbit that could hit things. We know the telescope is working; we’re getting data down, but nobody’s looking at it. What’s the condition of the outer blankets? Will we be able to open all the doors to get into where we want to do the work? So they want to have as early an idea of what shape the telescope is in as possible.

After that comes a set of spacewalks that follow up the spacewalks that took place on your last mission. This job seems, to the outsider, I guess, similar to the job that you had on your last mission. So I’m wondering, is the experience of having done this before helped you and your crewmates get ready to do it this time?

We are building a lot on that experience. There are three of us who flew together on the last mission and that’s a lot of value added to this flight, understanding where things can hang up, what things you need to worry about, how the preparation in the pool is great, and also the areas where the pool is not always perfect for what’s going on in space. There’s always something in each flight, I think, that is different on orbit than what you prepared for, so looking out for that and trying to bring that experience I think is going to help us get ready. But it is going to be five very packed spacewalks. This is the last time we’re going to Hubble, the last chance to make this as good as it can be, so we do feel that the pressure is on.

Does this mission feel different than the last one?

It does, in a couple of different ways. Realizing that fact, that we’re coming to Hubble for the last time that people are going there and as I look forward to this I think it’s my last flight on the shuttle, with the shuttle retirement right around the corner, so that part is a little different. But in the core of what we want to get done and the feeling of the preparation, the attention to detail, the ability to choreograph this whole dance as tightly as possible, is the same as last time and the same desire to get as much work done on Hubble as we can with the limited time we have to be up there.

You’ve got five spacewalks planned over five consecutive days coming up. Tell me about how you’re dividing up all the responsibility among the crew members, from helping spacewalkers get ready to go outside, to running the arm, to sitting back and watching it succeed.

Everybody has specific jobs. We’re going to train everybody in those specific tasks, but the key to success in my mind is that we all understand what our jobs are and we can do them to the best of our ability and a little bit more, so that everybody knows how to help somebody else out with something else, and if that’s your attitude that you come into this flight — I’m going to do my job and a little bit more — and we all do that, then we work together and we’ll get the most done that we can in working this. Five consecutive spacewalks is a high-paced workload for five days. You’re going to wear down a little bit and you just need to know that there are people there to give you that hand when you need it as things are changing or going differently than you expected. So I’m trying to put that out to the team and get us all together with that philosophy.

Amongst the group then, who does what?

We have four spacewalkers in two different teams, and they’ll alternate the days that they go out. But when they’re not out doing a spacewalk they’re not having time off — they’re the ones who are inside running the spacewalk, talking to the guys out there. And in some ways they’re concentrating even harder than the folks doing the work because they’re looking ahead, reading ahead, trying to think about what he needs next and making those calls. It’s pretty demanding. So there are four people who are working hard for five straight days. Then you’ve got the arm operator, Megan, who’s moving them all around. If she doesn’t put the arm in the right place at the right time it slows us down. We’re all set up to go bang, bang, bang, like that, so we can’t handle delays. And then you have to have somebody backing up the arm operator to help her move as quickly as she’d like to, and that’s one of my other jobs in addition to taking one of the EVAs and I’ll let her take a little bit of a break and she can back me up for that. Plus, on top of all this, so we’ve got six people busy 24 hours a day, practically, somebody’s got to take care of the space shuttle. There are little maintenance actions that have to be done. We’re doing different burns, attitudes, and that’s going to be my pilot helping me with that, and then me working on that as well. So it’s a total team effort and we depend on the ground as well, both in training and in orbit, to help us manage that workload.

Let’s talk about what you’re bringing and how that’s going to improve operations of the Hubble. The top priority components to be installed are two new Rate Sensor Units. What are those? What do they do?

Well, the Rate Sensor Units are basically the gyros and that’s what gives Hubble the pointing accuracy that it has. We’ve talked about it being able to point a laser from the top of the Washington Monument to hit a spot on a building in New York, the Empire State Building, for example. So having that precision is essential when you’re pointing 13½ billion light-years out in space. The gyros make that happen. Three of them have failed, so it’s a life extension process for Hubble to put new gyros in and ensure that it can last the rest of its life with that pointing accuracy.

Next on the priority list is the Wide Field Camera 3. Is that a, a big improvement over Wide Field 2? What does that camera see?

It’s kind of an order of magnitude, a new leap in technology, as we move on from what we had before, more resolution, more capability to look. It can see the visible spectrum, those great pictures that you see, but it also has capability in the IR [infrared] spectrum to extend Hubble’s range beyond just the visible and add that picture capability. One of the instruments right now that we put in last time has failed, the Advanced Camera for Surveys, so having that Wide Field in there will give Hubble an extended capability for those visual pictures.

You’re installing something called the Cosmic Origins Spectrograph that’s going to go in the spot that’s occupied by a component called COSTAR [Corrective Optics Space Telescope Axial Replacement]. What will Hubble be able to see with this new element?

The fact that we’re taking out COSTAR is actually a pretty cool thing because since Hubble was launched it had that optic problem and that’s where COSTAR was developed, and installed and was like the eyeglasses for Hubble so it could see more clearly. Now that’s all designed into the instruments. So being able to take COSTAR out means we can put a scientific instrument in that slot that was designed to have a scientific instrument. Hubble can now be functioning with scientific instruments in all its bays, which it never has had prior to now. So that is an exciting thing for me, that we can return Hubble to the way it was meant to be plus all the technology that’s been added over the years, and being able to install something like the Cosmic Origins Spectrograph, which is kind of the part of astronomy that doesn’t produce pretty pictures but focuses on extending our basic understanding of what’s out there. It’s helped us determine where planets are in other galaxies orbiting around different stars, things like that basic setup of the universe and understanding how that works. And that flows down eventually into the way we build things like computers and transistors. All that stuff has changed as we’ve understood quantum mechanics more and more, and I think this is another step in that direction.

You’re also bringing up two replacement battery modules, which would lead me to believe that these are not just batteries -- they are battery modules. How big is this? How long do these things last?

The good news is that Hubble has proved how long those rechargeable batteries actually can last if you’re careful with them. I know at home, charging my cell phone, I’m not as careful and all of a sudden it doesn’t hold a charge any more and you have to go buy a new battery. Hubble hasn’t been able to go buy a new battery and stick it in because it’s orbiting up there 300-plus miles above us. They have made their batteries last by managing that charge/discharge cycle very closely. So now these are the original batteries from the time it was launched. We’re talking 14 years old; it’s time to put new batteries in so that they’ll hold a charge better. There was a big concern that Hubble would eventually lose capability and without those batteries you don’t live through the night cycles when you can’t see the sun with the solar arrays. So we get to bring up the new batteries, install them, and try to keep Hubble’s power level high.

You’re also bringing up a refurbished Fine Guidance Sensor to install. This is something that’s been at Hubble, came home, and is going back?

That’s a neat part of the capability, to go there, service it, and bring that equipment home. The Wide Field Camera actually is also in the body of a previous camera that’s been -- you can’t really say “refurbished” because they took all the guts out and put new things into it. But we’re using that hardware, and this Fine Guidance Sensor has been refurbished. It works. There are two of them up there right now that are not 100 percent, so we had to decide which one to fix; we picked [FGS] 2. We’re going to take that old one out, put it back in the payload bay, and bring it home. People can look at it and understand what failed. How things fail in orbit is a key thing to know when you’re designing the next generation of spaceships to go places like Mars where you won’t be able to just launch a new part. So you can say, "Well, this failed here. I don’t want to use components like that, so I’ll design it a different way and prove that that’ll work for the long haul."

In the terms of this sense, how does this Fine Guidance Sensor work with other components in Hubble to get it looking in the right place?

The whole telescope has to work together, you know: there’s the rate gyros, the Fine Guidance Sensors knowing where you are so you know where to point. Actually things have to work together. The batteries have to work so you can get the power to the rate gyros, which then work with the Fine Guidance Sensors that we’re pointing in the right area of the sky and be able to take those observations. It’s amazing, to point that accurately for that length of time to take the exposures, to draw that faint light in, and produce the results that we get.

We’ve talked a lot about things you’re bringing up to replace old components, but your mission also has the task of repairing the Space Telescope Imaging Spectrometer. Tell me what it is that that instrument sees, what’s wrong with it and what are you going to do?

It’s basically a spectrograph, in some ways similar to the Cosmic Origins Spectrograph, but pointed at a different part of the spectrum. It again comes up with some of these basic understandings of universal laws and rules and it has failed for power. Now, they would like to bring a new one up and put it in there but we don’t have the room. So they’ve isolated the failure by tracking the data down to a specific card installed inside. This card was put in when it was built and it wasn’t planned to ever be changed out on orbit. They thought, "Well, you just bring the box out and bring a new one up." But, as they found where this failure is, they theorized that, "Well, if we went in here, opened up the doors, we could take out all these screws and then go in and pull the card out." The card is set up so that on launch, when it’s vibrating, you don’t want it vibrating out of place, so it’s locked in place with some 900 pounds of friction. So our job then is first open the doors, that’s something we’ve done on every mission so that’s good, then we go to a box but instead of pulling the box out we’re going to start taking these screws off. These screws are not EVA screws; they’re not captive. So when you undo them, it’s just like when I’m working on my car at home. If you let one of them go it falls, and you wonder where it went. In the telescope it just floats off, so we can’t have that. It would get in the wrong place. It could ruin the whole thing. We’re going to put a capture plate on the top of it and pull out over 117 of these tiny little screws, hopefully capturing them all, then pulling the plate off this thing that was never designed to be removed, and figuring a way to pull this card out with all the frictions locks that it has locked in there, and then pulling out our new card, sliding that in, putting a new faceplate on that doesn’t need 117 tiny screws. Eventually Goddard [Space Flight Center] turns the thing on and we see if it works again. And we think that it will and we’ll bring this instrument back to life.

STS-125 Commander Scott D. Altman participates in a training session in the Space Vehicle Mockup Facility at the Johnson Space Center, Houston. Photo Credit: NASA

That must have been a, a heck of a job to design something that would allow that work to be done?

It is an incredible blending of people looking at how to do the work and what people can do in space. We’re definitely pushing the edge of the envelope of what’s been done EVA to date.

A few minutes ago you talked about the Advanced Camera for Surveys not working. Well, the job of repairing it is spread out over a couple of EVAs. What is it you’re going to fix, and what will that let the ACS do to contribute to Hubble’s mission?

The ACS was really the high point of the instruments that we installed on the last mission. It had the longest reach, it took the most phenomenal pictures, and then last January it failed: We had a short and we lost power, and it was the best imaging system that was on board Hubble. So everybody then scrambled to see what we can do to fix it. We already had a full mission designed at that point. The good news was, because we’d been working on STIS already, looking at this screw EVA and we thought, well, you can go into the thing. People said, "Well, maybe we can do it again." I think if we hadn’t been doing STIS, people would have said, "Sorry, ACS is out of business, that’s way too far edge of the envelope." But we had the work that had been done to date on STIS repair. We took what we learned from that, went over to ACS and said, "Well, let’s take a panel off over there, pull some cards out, and put in a new power supply and power it back up, because we want Hubble to have a couple of ways of taking images to bring back down to the ground." So we tried to shoehorn that repair into the EVAs that we already had set up, and as we looked at that and the priority list, we said, "Well, we’d like to do it all at once but we can only fit about half of it on this day, and we’ll reserve time on the last day to go back and finish it up, if we can, so we can bring that system back." It’s just an incredible camera.

What, what’s the nature of the repair?

It’s basically pulling some cards out — it’s a power supply kind of thing. There was a short in there. It actually had two power sides. One failed earlier and then in January the other side blew out, with a pretty big short. They were worried about the instrument’s capability, but now we think if we put a new power supply in here we’ll be able to power it up and return full capability of the instrument.

There are also plans to install some thermal blankets; where do those go?

The thermal blankets are for the outside. They basically do the same thing that the blankets did for me last night when I was sleeping, keep you warm. They also insulate the instruments and can help keep it cool. The Hubble has a radiation environment that can heat things up — sides face the sun — so what’s happened is that while the Hubble was designed in the beginning with an outer covering to do exactly that, over the years the environment has caused it to split in places, come apart. We’ve done different repairs over the past few missions, and now we have a blanket designed to put over there and hopefully control the thermal environment so that you can keep the most things on as possible, to collect the maximum amount of data, and be able to send that down to the ground without overheating.

All of that is what’s planned, but NASA wouldn’t be NASA if it weren’t sending you up there with plans to do more than what we have planned. What kind of contingency priorities do you have in case you got a little extra time out there?

There are always a few extra things that you could do. We have some extra outer blanket layer things that could go on there. A lot of our contingencies are what do we do if we don’t have enough time, how you manage what is the most important thing to do, how you fit everything in. We have another piece of equipment we’re carrying is a soft capture mechanism which we’re going to leave on the bottom of Hubble so that a new vehicle could come up and dock with it and capture it more easily than I can with the shuttle. So that’ll be an improvement for it as well.

After five EVAs, time to put Hubble back out to work. Describe for us the plan for reboost and then for releasing it back into orbit in a stable configuration.

If we can, if we have enough propellant left, we’ll do a little bit of a boost and take it up a few miles to give it a higher orbit. It does decay a little bit every year, so the higher we get it, the longer time it would last in orbit, so that’s a good thing. The only problem with taking it up is that it makes it harder and harder for shuttles to get up there to get to it because Hubble is not as high as a shuttle can absolutely go, but it’s almost absolutely as high as the shuttle can go and come back from. We all like the coming back part almost as much as the going. So that’s good. So we don’t want to put it too high where you couldn’t get up to it and get it. But when we’re letting it go, we got to play the arm and commander team again. So Megan will go out there and grapple it at the back, then we lift it very carefully out of the structure that has been holding it because we’ve added this new piece on the bottom, so our clearances are a lot tighter than they were when we grabbed it as it go, comes out of those hooks. So I have to be careful with that. And then we bring it up closer to the front of the cabin, let it go, and then I fire a few jets and we sort of slip out from underneath it. The Hubble goes right over our heads. I couldn’t believe how close it looked on [STS-] 109 when it drifted by — you were kind of ducking as it went over the top. Then we sort of fly around it and let it go back to work out in space.

You’re very likely going to be the last people to lay eyes on Hubble as it floats away like that. Any thoughts on its contributions to science or plans for a good-bye?

I do think it’s been one of the most incredible scientific instruments ever built. You go back to things like Galileo and the telescope. It’s just been an incredible scientific instrument. It’s going to be a very bittersweet moment. Hopefully, we’ll be leaving the telescope in the best shape ever, so that’ll be a feeling of accomplishment, but it’ll be like leaving an old friend for the last time, so we’ll say good-bye.

When you go it’s still not ready to go back to work completely. When will the Hubble ground teams have it ready to go back to work full time, full strength?

It looks like it’s going to take a couple of months for Goddard to check everything out and feel comfortable turning it over to making scientific observations, and then pulling some of that data down and unveiling what we’ve done, how it’s all worked out. So we’re hoping that we’ll fly in the August time frame and then by the end of the year or early next year we’ll have some of those observations to look at.

I’m not sure if it’s ironic or just insightful, in that your mission shows us the need to have a crew of human beings around to get a robotic telescope in shape to continue its mission. Scott, what are your, your thoughts about the future of space exploration and how those two aspects have to work together in order to make us do that?

I think we’ll be able to look back on the Hubble and human collaboration as one of the things that we’ve learned from to make the exploration effort go forward. I think as we move farther and farther away from Earth, we’re going to have to work together with robotic functions like that to be able to do things, because we’re going to have to transition that control place from the ground. Right now the ground really helps us a lot, telling us what to do, how to manage things. But as you move beyond that, when you get to Mars, you’re talking about 40 minutes for a round-trip conversation. You better not be waiting on the answer of whether to stop or go for 40 minutes because you’re going to fall off a cliff. So I think that collaboration is going to be the key as we move forward. There’s a role for humans and there’s a role for automation and robotics and putting that together will make us the most successful we can be.