Preflight Interview: Gregory C. Johnson, Pilot
JSC2006-E-11466 -- STS-125 Pilot Gregory C. Johnson

STS-125 Pilot Gregory C. Johnson. 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 tell me what was it that motivated you, or inspired you, to become an astronaut.

A: Well, I think my track to become an astronaut, the path I took, was a little bit a spiral; I mean, it was a little curved. I didn’t have an outside plan I started out to want to be an astronaut. I think the motivation from the beginning is I like to do new things, learn new things; that’s probably the No. 1 priority. I sort of got bit by the flying bug as a youngster and so I asked to go to a school to learn to fly, and my parents did that for me. And then while I was putting myself through the University of Washington I flew seaplanes, commercial seaplanes. I got a chance to fly off glaciers, fly into northern Canada, do a tremendous amount of flying. I came to the point where I was going to graduate and go work for an aerospace company and the flying was too big a draw. And so I say, well, what kind of flying would I like to do? Flying off aircraft carriers seemed to be the most challenging so I went in that direction. And flying off aircraft carriers, I looked towards the next direction and that was to become a test pilot, so I did that. After that there was only one other flying job in the universe I wanted to do and now I’ve become a pilot for the space shuttle.

Why would one fly off a glacier?

We were actually delivering supplies to coastal geodetic survey people living on the glacier, so we actually landed our seaplane on the glacier with all their supplies and then took off downhill.

Let me take you back earlier than that. Tell me about growing up — your hometown is Seattle. What was it like growing up there in [the] ’60s and ‘70s?

It was a great place to live. We were always outside, did skiing. It was a, a wonderful childhood. Lots of land, lots of trees, lots of water, lots of mountains, camping. It was just a great place as a kid to grow up.

Do you have a good sense of how that place and the people that were there contributed to making you the person you are today?

My parents were really, really great about saying you could do whatever you wanted to do. You know, "You can do it." And they were very big on doing the best at whatever you did. Whatever you decided to do, just do the best. That was sort of their overarching advice. So I always tried to do my best. Then I just naturally gravitated to kind of the scientific area as my interest. So from there it was flying. I ended up being an aeronautical engineer because I was interested in flying.

Tell me about your education and your professional life that led you up to here. Take us through the steps and the different things that you’ve done, the many different things that you’ve done.

I graduated from high school and I had done well and so I proposed a school to my dad and, he had said, well, you know, the University of Washington is a good school — the school he went to — and so I had kind of a plan B: "Well, I’d like to do that but then I’d also like to learn to fly." So it was sort of a negotiation of a place to fly. So I went to a community college, actually, in eastern Washington, and learned to fly there. It turned out they had a seaplane club and I ended up being the vice-president of the seaplane club and learned to fly seaplanes. And so when I went back to Seattle, I ended up trying to get a job on the weekends flying seaplanes. I ended up doing that for three years while I went to the University of Washington. From there, it was going into the Navy and then from there, getting a degree at the United States Air Force Test Pilot School and then on to a test tour.

And a lot of different stops in the Navy as well, I think.


How did, when did you first come to work for NASA?

I worked for NASA in 1990; they offered me a wonderful job as a research pilot. I ended up flying the KC-135, microgravity airplane, and also the WB-57, in a full pressure suit at high altitudes. So I did that along with flying T-38s and the Gulf streams. So I had quite a flying career out there.

Where in all of that did you ever apply to be an astronaut?

I had interviewed in the Navy and most astronauts don’t, at least I didn’t, get selected the first time. So I had interviewed in the Navy and then interviewed while I was at NASA. On my third try I got selected.

Tell me how you got the news that you had been assigned your first spaceflight?

It was really nice. The chief of the office, of course, asks you. You get a phone call from his secretary, you know: “The Chief would like to see you.” That can either be good or bad. I always hoped it was going to be good. I hadn’t been back very long from the Kennedy Space Center as the manager of launch integration, so he came in and just asked me, "Would you like to be part of the Hubble mission?" Of course, I was smiling and said yes. It was just great news for me because it was a pure science mission.

We all know that flying in space can be very dangerous. Greg, tell me what you think it is that we get as a result of flying people in space that makes it, the risk, one that you’re willing to take.

I think people are able to, on the spot, look at a set of information and set of data and make a decision with maybe not quite enough information, but using their experiences, their background, intuition, and melding that whole process real time in space, I think that’s the benefit. You could plan it all out on the ground, it might not go as planned, and I think people, you know, be able to process all that information and make it a good decision, and I think that flexibility real time is what makes people in space. And then just the exploration part of that. It, it would, it’s great to see the rovers on Mars, but it will be just fantastic to see a human being on Mars.

When was the first time you ever heard of the Hubble Space Telescope?

You know that, that’s a great question because I joined NASA in April of 1990, and a day after I joined we launched for the Hubble mission. That was the first time I’d heard of it -- specifically the aberration of the mirror. So when I heard about that, that was kind of my first introduction to Hubble.

What do you think Hubble has meant to the science of astronomy in all the years that it’s spent gathering data?

Hubble is maybe the most powerful instrument in astronomy we’ve ever produced. It’s about 10 times better than a telescope on the ground due to the fact that it’s out of the atmosphere. To try and say what it has meant to astronomy or to exploration is a really broad question but I can take it down to a couple levels that I think are very interesting. Edwin Hubble talked to Einstein; the two of them talked. I think that, I find that to be, just incredible that they got a chance to talk. One of them was looking at empirical data, Hubble looking at his telescope, Einstein doing it on a blackboard. And the fact that they talked to each other, and eventually Hubble determined that the universe is expanding, and then accelerating. I think [that] is one of the single most important discoveries in my lifetime, to me, anyway, in science. So that I think is very important. The fact that we actually proved we had black holes -- we always thought we had black holes -- I think that’s just phenomenal. The fact that we maybe found over 250 exoplanets out there way out there and, and then Hubble himself deciding the age of the universe, you know, with his constant called H0. I think those are just fantastic discoveries and the telescope has certainly lived up to its name as being the most powerful and probably the most popular scientific instrument.

Well, there are a lot of people who are involved in getting you ready to fly this mission, and not just here in Houston. Talk for a minute about the training and the support that your crew’s received from the people who are behind the Hubble Space Telescope at the Goddard Space Flight Center and the Space Telescope Science Institute.

Some day 10 years from now I’m going to say I was a small part of this Hubble mission, hopefully a Hubble successful mission. But the people at Goddard are incredibly dedicated. The enthusiasm is pretty straightforward. We have manned spaceflight here at the Johnson Space Center, but at Goddard they don’t get a chance to see the crew members and they have [a] tremendous amount of questions. But, their attention to detail in getting the Hubble ready, the picking of the detectors, for example, for the instruments and the care that they do that, the teamwork. As a team they work incredibly well together. They always have their meetings where they try to decide one way or the other and pair off, this way to do it or this way to do it. Just working with them as a team, it’s really an honor to be a part of this and really a small part of it because the effort is done in the background.

It’s no surprise that the people who work on the project have a great affection for it, but Hubble has really become an icon outside of the science community. Why is it that it’s got such a special place in, in the hearts of everyone?

I think their Wide Field Camera 1, then we had 2 and hopefully we’ll put 3 in, brought some of the most beautiful images we’ve ever seen of the universe. I think that caught the public’s attention. The fact that it has spectrographs on it and it gets the chemical composition of the universe for the astronomers is sort of a combination of you can get the public involved because you can show them these pictures, you can get the astronomy, the science community involved, and it marries the two of those together, and it’s just phenomenal. It’s been a great payoff.

What’s your favorite Hubble picture?

Mmm; that’s a difficult question but I have one that I think is very, kind of, first. It started out as a pretty picture, and secondarily then I learned a little more about it, but it’s called the Cat’s Eye Nebula. It was found in 1994. Obviously we launched Hubble in 1990, we fixed its optics in ’93 and in 1994 they found this nebula outside of our galaxy. The picture is just astounding. The colors are just astounding, but every 1,500 years or so it's one of my favorite.

You’re the pilot on this servicing mission to the Hubble Space Telescope. Greg, summarize the goals of the mission and tell me what your main responsibilities are going to be.

I think the goals of the Hubble mission, the Servicing Mission 4, are really to maintain the space telescope, adding batteries, changing out Rate Sensor Units, Fine Guidance Sensor, but then to upgrade it with the new Cosmic Origins Spectrograph and the Wide Field Camera 3. The first goal, I think, is sort of the Hippocratic Oath: you know, do no harm. We really don’t want to end Hubble’s discoveries by our mission, so we want to keep Hubble going being careful in what we do. So we want to fix as much as we can; we’ve got two instruments we have to fix, Advanced Camera for Survey[s] and, the spectrograph that’s not working. We’re going to try and fix those, add two new instruments, and then just kind of refurbish the telescope. That’s kind of the overall goal.

What is the job of the pilot on a mission like that?

Well, the pilot’s a bit of a jack-of-all-trades but certainly the three main areas helping the commander. On ascent, of course, I’ve got four of the main subsystems — the main engines, the orbital maneuvering system, reaction control system and electrical power system, and actually the auxiliary power system — all those have switches you don’t want to hit in, in the wrong order and then, of course, that’s ascent, and entry. On entry I’ll help the, the commander, my opinion on, on the landing and how we’re doing on the landing and, and then help him for the landing. And then we’ll do the rendezvous together, too, so those are our three core areas that I think the pilot helps. And, of course, I’ll be watching the commander to see how he runs the mission and sort of, big picture; hopefully give him my perspective on the mission. If we’re getting behind in timeline I can give him my perspective on that. Then during the mission itself, I’ve got a couple of tasks. Photo/TV is a big one. Of course, I’ll hopefully get some of these spacewalkers' images to the ground, from their wireless vision system, get that to the ground -- document the mission. I hope to take a picture of a high-five of Megan [McArthur] and Scooter [Scott Altman] when they get this telescope, for example. So photo/TV is a big part of it. I’m also, it turns out, to be one of the medical people involved, so I hopefully won’t have to do anything in the medical area. I think probably during the spacewalks, the five days of continuous spacewalking, I’ll help the crew members get in their suits and then help them get out of their suits.

After the loss of Columbia, this Hubble servicing mission was actually canceled; it was decided it was too risky. But that decision was reversed almost two years ago, and here you guys are. What was your feeling about the decision not to make the attempt, and then your feeling about the change of heart and the decision to go ahead and fly this mission?

“Risk” is an interesting word. I’ve been in a lot of risky business. I consider flying off aircraft carriers twice a day every day to be a risk that I was willing to take. My initial cut on canceling the Hubble mission was that it was a shame. I didn’t know the technical details of what risk levels, they had determined were too great; so my general idea was it was a shame. I think the fact that they have done so much to the external tank to reduce the shedding from the tank and then they’ve put another space shuttle on the other launch pad to be launched within five days or so, I think mitigates the risk down to an acceptable level. But it is still very risky. And [it's] slightly more risky because it’s at higher altitude and slightly more risky because it’s in 28.5-degree inclination. Those combinations make it a little more risky for MMOD [micrometeoroid orbital debris] hits.

Well, let’s talk about some of the, the ways that you deal with that risk. Like all shuttle flights now, yours will include a thorough inspection of the vehicle using the Orbiter Boom Sensor System. Tell me about how that inspection’s accomplished and what it is you’re looking for.

Well, specifically you’re looking for, any problems on the RCC [reinforced carbon-carbon] panels, for example, the leading edge of the wing, the bottom edge of the leading edge of the wing being the hottest. Any problems an eighth to a quarter inch through those panels, and then we’re going to have a problem on re-entry. So we’re kind of looking for that. And then eventually we’re doing a view of the entire orbiter, including the nose cap, and the underside, specifically for the Hubble mission. We won’t have the RPM [rendezvous pitch maneuver] that we would do at the International Space Station, so we’ll do a, kind of a self-look with our own Orbiter Boom Sensor System to look at the tiles on the underside of the orbiter. My position on that is R3, I’ll be working some of the data to the ground, the recording to the ground, also looking at the DOUG [digital onboard ubiquitous graphics] computer system and backing up Megan and Scooter on the checklist.

JSC2008-E-035360 -- STS-125 Pilot Gregory C. Johnson

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

Now, several possible means of repairing a damaged shuttle on orbit have been tested since Return to Flight. For your mission, what could you guys fix if you had to?

Well, I think one of the most powerful fixes is called emittance wash, just something you brush on. That’s certainly in our bag of tricks. Whether we actually use a plug, something that we would fill over the leading edge of the wing, those will be on board to be able to use in a last-ditch effort and then overlay if we have to put anything over, or fix some of the tiles. Right now I think we’re in pretty good shape. If we had to do that we could. We’d also, of course, decide whether you’d want to bring up STS-400, the rescue mission, so the combination of those two, in my opinion, a small damage we might repair in combination with the rescue mission, makes the risk manageable.

The emittance wash is, would be used on the tile areas, correct?

Correct, yeah.

Well, on, you mentioned STS-400, because unlike other shuttle flights that go to the International Space Station, that safe haven is not an option for you on this flight. What are the options in terms of a rescue? How would that be carried out?

You know I think, I think the public hasn’t really gotten a hold of the Hubble mission yet. We’re not ready to fly quite yet, but certainly when they see space shuttles on each launch pad, I think that will come. The public will realize, OK, now we really are able to launch a rescue mission. The concept there, of course, is if we find damage on flight day 2 that we couldn’t repair -- that’ll take flight day 2 to get the data and it’ll take over 24 hours to look at the data and decide if we really have a problem. But then once they make a difficult decision with the Mission Management Team to launch the rescue mission, they would launch from the other launch pad with another crew, a crew of four. They would come up and they’d rendezvous with us. We would grapple each other, robotic arm to robotic arm essentially, and then we would transfer crew members between the shuttles.

By spacewalk.

By spacewalk.

So here’s hoping you don’t get to make a spacewalk on this flight.

Right. And I, you know, I’ve gotten into the EMU [extravehicular mobility unit] suit, and we will probably practice that in the pool. I get to, to walk in the pool, the NBL [Neutral Buoyancy Laboratory], as a pilot, which is kind of rare, and then just in the case that we have to do the spacewalk.

Well, all the work that you’re planning to do to get Hubble up and running at full steam is contingent on a successful rendezvous, grapple and berthing of the telescope. Tell me the part that you play in that portion of the operation. Describe how you go about getting the telescope onto that work platform in the payload bay.

I think it’s going to be exciting time. We’ll do some phasing burns to get to rendezvous with the telescope. I’ll be doing those burns, some of those burns, from the commander’s seat and then Scooter will be in the back looking through the optical site at the telescope, along with Megan monitoring the robotic arm. I’m sort of the timeline master, the checklist master, so I’ll make sure that we haven’t missed a step in the checklist. I’ll be looking at the displays, and talking to Scooter about the rendezvous. Of course he’ll get the space shuttle right near Hubble, stop it right next to Hubble, basically, in a very good position for Megan to go out and grapple it with the robotic arm. Once we get the grapple, then Megan will very gently lift it—the size of a, you know, a small bus—and put it into the payload boy, bay on the structure of the FSS [Flight Support System], and then from there we’ll be able to move the, Hubble in a circle to open up different sides of the Hubble Space Telescope.

What kind of flying task is the formation flying of these two things at that speed?

Once you get kind of close it’s like flying an airplane. It’s like rendezvousing with an airplane or a formation on an airplane. On the rendezvous we’ll come up from the essentially what we call the R-bar, a line between the center of the Earth to the Hubble. At about 100 feet we will go in an inertial hold — Hubble going around the Earth in a certain inertial attitude. We’ll match its inertial attitude and then Scooter will use the berthing camera to put Hubble in the camera view right down the center. We’ll just press on up towards it so if all goes well and it’s in the attitude we think, it should go pretty straightforward.

Once it’s berthed, and actually before the first spacewalk, there’s a couple of hours in the timeline set aside for a survey of Hubble. Tell me about that task and what you are looking for here?

Hubble’s been up there for quite awhile, since 1990. It gets hit by MMOD — I think it’s had a hit through one of its solar arrays — so we’ll be looking very closely for how has Hubble deteriorated since it’s been up there, and since the last time we’ve been up to the space telescope. It goes through an incredible thermal cycle each 90 minutes so that takes a, a toll on it. Certainly MMOD takes a toll. We’ll look to see if any of the blankets are frayed, if any of the blankets have come loose, and any deformities we can see on the space telescope itself. But that’ll, that’ll take a couple hours of, of very closely documenting the telescope.

And as you mentioned a moment ago, the timeline calls for five spacewalks to be conducted over five consecutive days. Before we talk about what happens outside, tell me about how you divide up the work inside, from helping spacewalkers get ready to go outside, to robotics operations, to communicating with Houston, whatever.

That’s a good question. Scooter and Megan will be sort of on the robotic arm backing each other up, and, if you think about the spacewalks, you know, they’re somewhere 6½ [hours] to maybe even longer so at that time frame, the spacewalkers, of course, have to have their attention immediately on the task, but also the robotic operators do, too. I’ll be down below with the off-duty spacewalkers helping suit up the spacewalkers for that day — get them suited up, checking out their comm, getting them into the airlock and then let them go. Hopefully we’ll protect Scooter and Megan because their seven hours of hard work’s coming up, so I’m sort of filling in with the other two spacewalkers to get them ready.

And the spacewalkers who are not outside will be working to try to coordinate them?

They’ll be the IV [intravehicular crew member] on inside, just making sure that each task is done correctly, that they haven’t forgotten anything, looking for the safety of the crew member, for example, outside, and so they’ll be the reminder and, and sort of the checklist monitor for the whole spacewalk.

And you’re going to be overseeing everyone?

I’ll be watching everyone but also their wireless video; I’ll be adjusting their wireless video, taping of the entire spacewalks.

I’d like to talk about what you’re delivering to the Hubble Space Telescope and what these different things are going to do. The top priority components that are being installed are new Rate Sensor Units. Tell me what those are and, and what they add to the telescope.

Well, the telescope has three Rate Sensor Units with two gyros in each, and along with the Fine Guidance Sensor it allows it to point very accurately, at a point in the sky. I think kind of the public doesn’t understand but when we point and look and take a picture, we’re looking at data for like three hours; we’re pointing at one spot for three hours, so the Rate Sensor Unit along with the Fine Guidance Sensor, those two get the pointing of the telescope very accurately.

The other top priority is the Wide Field Camera 3, which I presume is better than Wide Field 2 or 1.

That’s correct and Wide Field Camera 3 is a very large jump in capability, maybe 10 times more powerful than Advanced Camera for Surveys. It works in the UV/IR [ultraviolet/infrared] areas, in a, in much broader spectrum. I thought it was interesting that the detector that they got for the Wide Field Camera. They've got hundreds of detector chips and finally cherry-picked the best chip with the best detector for the camera. But it’s what gives us those, those pictures, those astounding pictures, and it should be probably 10 times better than what we have right now.

Got to be kind of hard to imagine. You’re installing a component called the Cosmic Origins Spectrograph that’s going into the spot that’s occupied by a thing called COSTAR [Corrective Optics Space Telescope Axial Replacement]. What will Hubble be able to see with this new element?

You know, it’s interesting. COSTAR was obviously installed because we had corrective optics and we were off by maybe a 50th of the width of a human hair is all. We took off a little too much material. We put corrective optics in. Now the new instruments actually come with their own corrective optics so we don’t need to actually have COSTAR any more. We’re going to put in COS, the Cosmic Origins Spectrograph, and that allows the astronomers to look at the chemical composition of the, the interstellar medium, for example, or intergalactic medium. And that’s probably their passion, to find out what’s out there. We know 5 percent of what’s out there, and 95 percent we don’t know what’s out there. And they’re looking for that kind of 95 percent, so Cosmic Origins Spectrograph is going to be a very large jump in discovery power for the telescope.

But not taking the pretty pictures, but providing other important data?

Reporting the data.

You’re bringing replacement battery; it doesn’t say “batteries,” it says “battery modules.” How big are these things and any sense of how long they’re expected to last?

The batteries are kind of interesting. The batteries were built years before Hubble went up in 1990. Those batteries still exist today. They were deteriorating and by changing sort of the solar charge, you know, discharge cycle, the batteries have held out. They weren’t actually supposed to hold out this long. They were going to be replaced on an earlier servicing mission, and they got pre-empted by a higher priority task. But these new battery batteries, two per module, are going to be replaced just because it’s a good idea for the final servicing mission. They’re large suitcase-size type batteries, and hopefully, they’ll work for the rest of the mission. Right now, Hubble’s working fine on its existing batteries but you never know so, they’ve been up there for, you know, almost 18 years so.

I guess the new ones will last for the rest of the mission, by definition.

By definition.

You mentioned this a minute ago, a refurbished Fine Guidance Sensor that’s going to be installed. Give me a sense of how the Fine Guidance Sensor works in conjunction with other components to get Hubble pointed where the astronomers want it to look.

Well, they decide where they want to look in space, and then they decide, you know, what stars are near that, and the Fine Guidance Sensor locks onto those stars of course, stars being out almost to infinity, and then that’s what holds the, the telescope to look at very precise point in the sky. So precise you could if you aimed the Hubble, for example, it can see the distance between Colorado and Washington, D.C., in terms of lateral distance, the width of, you know, the diameter of a, a dime. So that’s the kind of pointing we’re talking about, very precise.

You talked about replacement of things but in this case you also have the task of repairing the Space Telescope Imaging Spectrometer, the STIS. What does the STIS do and what does it have to have fixed on it?

Well, the STIS is just another level of spectrograph looking at the whole, electromagnetic spectrum but it’s got a problem where one of its circuit card’s bad. Now having personally taken a circuit card out of a computer, I can’t even imagine how hard this task is going to be. However, they’ve gotten it down to what appears to be a successful capability to pull a circuit card out of the telescope, open up the LRU [line replaceable unit], pull the circuit card out and put a new circuit card in. That’s essentially what we’re doing for STIS. We will get feedback when we put these instruments in; we’ll get sort of a continuity check feedback, pretty quick feedback on [whether] everything’s talking to everything. We don’t know if it’s going to work yet but we’ll get feedback that it did or didn’t work. And we’ve been practicing this STIS task; it’s been on the mission for quite a while. I think it looks like it could be pulled off. My sense of concern for the mission might be the repair portion, STIS and ACS.

Because it’s a task that was never intended to be done by spacewalking astronauts, right?

Correct. And I think this goes to where, you know, human servicing of this telescope is so important. It’s just absolutely critical. We would not have been able hopefully to fix the spectrograph, without humans in space.

Well, let’s talk about the ACS. The job of repairing the Advanced Camera for Surveys is actually spread out over a couple of different EVAs. What are you going to fix and what will that let ACS do?

Well, the Advanced Camera for Surveys, of course, is another camera system. It actually has three cameras in it but it had a large short, in the, very high amp kind of short, and it looks like we burned something out. We may have burned out everything short of the detector. So essentially we’re going to take out the detector and then all the electronics, power supplies that drive the electronics, we’re going to replace all that. My concern is that we haven’t practiced this that much and we don’t exactly know what went wrong with ACS. So … everybody will be extremely happy if they happen to be able to fix it.

Well, it sounds like the job may change once you get there and see what’s actually going on?

Yeah, it could change. That continuity check after ACS I think is going to be very important.

JSC2008-E-018320 -- STS-125 Pilot Gregory C. Johnson

Attired in a training version of his shuttle launch and entry suit, STS-125 Pilot Gregory C. Johnson awaits the start of a training session in the Space Vehicle Mockup Facility at Johnson Space Center, Houston. Photo Credit: NASA

You’ve also got the task of installing some blankets on the telescope. Where do these go?

The telescope has thermal blankets on the outside, of course, and we’re bringing up three blankets, hopefully going to install one of those three is in the timeline at the moment. If we get ahead of task, for example ACS is done quicker, then we might be able to get the other two blankets, and this is just more of a maintenance issue on the outside of the telescope.

Of course, NASA wouldn’t be NASA if they weren’t sending you up there with more tasks than you think you really have time for. What other kind of things are you going to do if the time allows?

One of the interesting extra missions, if you will, is the soft capture mechanism that we would put on the bottom side of Hubble. that’s going to be there in a, the capability to possibly robotically, you know, rendezvous with the Hubble, maybe CEV [crew exploration vehicle, Orion] for example, to de-orbit Hubble. So that’s kind of one of the extra ones. And I alluded to the other two NOBL [new outer blanket layer] blankets if we get a chance to get those installed.

OK. After five spacewalks are conducted it’s time to let Hubble go back to work. Describe the plans for reboost, maybe, and then for releasing the telescope back into orbit in a stable condition.

A reboost is kind of interesting because, we haven’t decided exactly how much we’ll reboost. I think it’s a function of propellant at the time, but probably no more than 10 miles. Hubble being in a 300 mile range we’ll probably bring it up to maybe, you know, 10 miles at the most greater than that. However, Hubble is up higher than the space station. So if we did nothing to Hubble, and it has no propellant, it will stay up there until about 2023 depending on the solar cycles. So just doing nothing at all, Hubble’ll be there for quite a while.

Then you come to the, to the point where it’s, you’re ready to turn Hubble loose. Talk about what it takes to put it back into space by itself and leave it in a stable configuration.

I think when we get to that point there’ll be seven people on the aft flight deck trying to look at Hubble to say good-bye for the last time. Of course, Megan will be on the robotic arm lifting Hubble out of the payload bay. We’ll release it -- there’s some very tight clearances as she gets it out of the payload bay now that we added the soft capture mechanism on the bottom, the clearance has just got significantly tighter -- so she’ll be very careful. But once we get Hubble into the bay, we’ll just go ahead and release it and pull the robotic arm away and then Scooter and I will do burns to get away from the Hubble Space Telescope. Of course, we’ll be snapping pictures the whole time.

You guys are going to be the last people ever to lay eyes on Hubble as you’re doing all of that. Any thoughts about what that’s going to be like?

First of all, we might not be the last people. You never know … could be another mission. But yeah, it’ll be a sad good-bye for certain. I’m really looking forward to seeing it for the first time, also.

When will the Hubble ground teams be able to have it ready to go back to work full time, at full strength?

We’ll do this sort of continuity check after we install things, kind of a “light bulb” test. Then it’ll be around two months later that the Payload Operation Control Center will be able to start getting data from Hubble. I think there’ll be a big cheer if we get some really good information.

It’s sort of interesting to see that in this particular case, in order to get a robotic telescope to be working at its very best, it takes a crew of little human beings to go out and do that work. Greg, talk about what are your thoughts about the future of space exploration and how both robotics and human elements are going to be involved in that.

I think it’s a combination of both. You know, with the Mars Observer and the rovers we’ve demonstrated the absolute strength of robotics. However, if we can actually fix STIS, that spectrograph, by putting a new circuit card in there, you sort of prove the human element involved. So it is very important. I see space exploration accelerating — just like the universe is accelerating, I think it’s going to start accelerating pretty quickly both in the civilian sector where they start to explore space. It’s going to be a big time. The whole space bowl of things to do is getting bigger. I think the moon and Mars initiative are critical to NASA, exactly what we should do. So we should stay in the risky business part of space exploration and keep up the robotic missions. Those are all just wonderful payoffs.