Hubble's Amazing Rescue

PBS Airdate: October 13, 2009
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NARRATOR: The pressure is on to save a dying explorer, the Hubble space telescope.

CHUCK SHAW (Director, Hubble Servicing Mission): It's the most productive science instrument that's ever been made.

NARRATOR: But can Hubble be saved?

CHRISTY HANSEN (NASA Astronaut Trainer): We're changing an electronics card out. We've never done that on orbit.

NARRATOR: It will take a massive effort by a cast of thousands, and NOVA is there each step of the way.

JOHN MACE GRUNSFELD (NASA Astronaut): Looks like the teeth are rounded out.

MIKE GOOD (NASA Astronaut): So the screw is stripped?

JOHN MACE GRUNSFELD: It went miserably.

NARRATOR: Despite years of preparation, there's no guarantee things will work in space.

MARK JAROSZ (Goddard Space Flight Center): We get one shot.

TOMAS GONZALEZ-TORRES (Lead Spacewalk Instructor): Things will go wrong on orbit; they always do.

NARRATOR: Seven astronauts put their lives on the line.

NASA SPACE SHUTTLE MISSION CONTROL: Crew members are an hour and a half behind the timeline at this point.

SCOTT ALTMAN (NASA Astronaut): If we are stopped here, it's over.

MIKE MASSIMINO (NASA Astronaut): It was unthinkable. I was ready to wake up from the nightmare.

NARRATOR: Up next on NOVA: Hubble's Amazing Rescue.

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NARRATOR: A daring mission is about to begin: the final repair of the Hubble space telescope. It's a mission so dangerous that for years NASA refused even to attempt it.

MIKE MASSIMINO: We've had accidents, and we've stopped flying shuttles for a very long time.

GREG "RAY J" JOHNSON (NASA Astronaut): You do your best and you hope for the best, but there are certain risks that remain on the table, and you have to step up to the plate.

MEGAN MCARTHUR (NASA Astronaut): Risk is something that we think about and that we talk about, but I believe in this program.

NASA SPACE SHUTTLE MISSION CONTROL: All crew members onboard.

NARRATOR: To fix Hubble, seven astronauts will spend two weeks in a vacuum full of extreme temperatures and deadly radiation. Yet the greatest risk comes not from being in space, but from the vehicle that takes them there: the shuttle.

CHUCK SHAW: When the shuttle lifts off from the pad, it's burning about 11,000 pounds of propellant per second. There are indescribable forces going on. You're a meteorite with people in it.

MATT MOUNTAIN (Director, Space Telescope Science Institute): The risk of dying is one in 70. I mean, it's incredible; these are very brave people.

JOHN MACE GRUNSFELD: So I think each individual astronaut has to ask themselves the question, "Is this risk worth it, traveling 1,500 miles per hour?"

NARRATOR: The object of all this risk circles 350 miles above our planet, the Hubble space telescope.

The size of a school bus, weighing 12 tons, Hubble is the best-known scientific instrument in history. It has revolutionized astronomy and brought us unprecedented views of the universe: huge pillars of dust and hydrogen gas; inside these clouds, new stars are being born; a very long exposure of a tiny dark spot in the sky that appeared almost empty. Instead, astronomers found thousands of galaxies, each with billions of stars.

Hubble is a time machine, showing us how our universe looked 13-billion years ago.

It has brought new insights into how planets are born, how stars die, massive black holes, where gravity is so strong even light itself cannot escape, and how a mysterious dark energy seems to be accelerating the expansion of the universe.

MATT MOUNTAIN: Twenty years ago, before the Hubble flew, we didn't know how big the universe was or how old it was; because of Hubble, now we do. We didn't know that black holes really existed; because of Hubble, we now know that black holes are everywhere. The Hubble telescope was the first telescope to actually examine the composition of a world around another star. Without the Hubble, none of those things would have happened.

NARRATOR: But now Hubble is failing. Half its science instruments, including the camera that took these pictures, are already dead.

Like a patient requiring multiple transplants, the telescope needs an enormous amount of work: remove an old camera, install a new one; swap out gyroscopes; remove old optics; install a new spectrograph and lots more.

NASA SPACE SHUTTLE MISSION CONTROL: Approaching staging, the burnout of the twin solid rocket boosters which have been burning fuel at a rate of about 11,000 pounds per second...

NARRATOR: The only hope to save Hubble is this mission.

Once in orbit, it will take Atlantis two days to catch up to Hubble.

NASA SPACE SHUTTLE MISSION CONTROL: ...Megan McArthur now repositioning the shuttle's robotic arm to align with the telescope...

NARRATOR: On Day 3, robotic arm operator Megan McArthur gently grabs the telescope and lowers it into the shuttle's payload bay.

SCOTT ALTMAN: Houston: Atlantis. Hubble has arrived onboard Atlantis.

NARRATOR: The next day, the repairs will begin.

MIKE MASSIMINO: We're in the middeck of space shuttle Atlantis, with my buddy John Grunsfeld over here.

JOHN MACE GRUNSFELD: And our spacesuits are here, and we're getting ready to go outside.

NARRATOR: The work will take five days, five spacewalks. But this mission has been years in the making. The preparation began long ago.

It's 2006 when the astronauts are selected: Scott Altman, commander; Greg Johnson, pilot; Megan McArthur, robotic arm operator; and four astronauts who will go outside and do the repairs, the spacewalkers.

They'll spend two and a half years getting ready, but they won't be doing it alone. To pull off a space mission takes a cast of thousands—engineers, technicians and planners, instructors—all helping seven people prepare for the most important mission of their lives.

Success or failure will all come down to those spacewalks, just six and a half hours each.

JOHN MACE GRUNSFELD: Well, that's not a lot of time. It has to all go perfectly to make that six hours and 30 minutes. That's the prime reason why we train, we train, we train some more. And we have to really know our stuff.

NARRATOR: Lead spacewalker on the mission is John Grunsfeld; he's been to Hubble twice before. John's partner is Drew Feustel; this will be his first flight.

DREW FEUSTAL (NASA Astronaut): We kind of operate on a buddy system. One person does the work, another person's handing off tools, providing support.

JOHN MACE GRUNSFELD: Okay, the first guide roller's in, second guide roller's in. I've got to back out.

NARRATOR: Today they're in Houston, learning to replace one of Hubble's cameras, called wide field.

The wide field camera has captured many of Hubble's best known images. Like all instruments on Hubble, it's huge: the size of a piano and it weighs 800 pounds.

DREW FEUSTAL: John, are you ready?

JOHN MACE GRUNSFELD: I'm ready.

NARRATOR: To practice moving this massive object in zero gravity, Drew and John are using a trainer that suspends the camera as if it were weightless, so they can learn how it feels to push and steer it.

JOHN MACE GRUNSFELD: Okay, keep coming in. Turn your end down just slightly.

It's very hard to get a feel for the moments of inertia and the mass, not in terms of having to lift it, but in terms of once you get it started, what does it take to stop it? What does it take to reorient it?

NARRATOR: Even weightless objects still have mass. In space, an astronaut pushes a golf ball, it moves, but if he pushes a piano, he'll move in the opposite direction. Piano, astronaut and golf ball are all weightless, but each has different mass and inertia.

STORY MUSGRAVE (NASA Astronaut, Retired): You've got to be careful you don't get into trouble.

NARRATOR: Astronaut Story Musgrave did three spacewalks on the very first Hubble repair mission in 1993.

STORY MUSGRAVE: This is the way I'm going to be holding it.

If I'm trying to push this object, and I get this object moving...okay, it's moving, but now it starts to pull me. Have I planned to have something to stop me from going that way? And if I have not, I'm gone.

CHRISTY HANSEN: Keep pushing down.

ASTRONAUT: Seems like it's still falling on its own.

NARRATOR: But here, on solid ground, this trainer only gives them one small part of the feel of working in space. So how do they practice spacewalking when there's no place on Earth to experience the bizarre condition of weightlessness?

MIKE MASSIMINO: You know, it's hard. You know, if you're going to play a baseball game, you can go out to the field and take batting practice with a baseball and your uniform and a bat. But to go to space, you show up for the World Series without practicing on the field, so to speak, so you got to get all your practice in other places.

NARRATOR: The best place to practice spacewalking is in Houston, Texas: the Neutral Buoyancy Laboratory—200 feet long, 100 feet wide, 40 feet deep; 6 million gallons of water. Able to hold a life-sized mockup of Hubble, it's staffed by scores of safety divers, suit technicians, riggers and crane operators. If you want to learn spacewalking, this is the place to be.

MIKE MASSIMINO: The Neutral Buoyancy Lab is a fancy name for a big, giant pool. It's like a lake. It's big, and we can fit a whole space shuttle in there, plus a whole space station. It's huge.

NARRATOR: Mike Massimino leads the second spacewalk team. He worked on Hubble in 2002. Massimino's partner is first-time flier Mike Good.

Today, Massimino and Good are learning how to replace three units containing gyroscopes. Gyros help point the telescope; changing them is tricky.

MIKE GOOD: Where these gyros live in the telescope is a very tight spot. You know, it's like working on your car, and you're trying to get at bolts that are just hard to reach and hard to get to.

NARRATOR: Learning how to do the gyros, or any job on Hubble, starts with learning how to work in a spacesuit.

MIKE MASSIMINO: It's not like you're in your, you know, your regular clothes. You know, if you're going to go run a mile, you don't put on one of these spacesuits; baseball players don't wear this stuff neither.

NARRATOR: The suits weigh over 300 pounds; on Earth, astronauts can't even stand up in them. But once in the water, everything changes. The suits are adjusted to be neutrally buoyant, neither rising nor sinking, just floating, as if in space.

MIKE MASSIMINO: And that enables us to practice our spacewalking. We can egress the space shuttle and move along the handrails and work with the telescope. And it's very close to learning the body positioning and the skills you need to spacewalk.

NARRATOR: But even this is still a far cry from true weightlessness.

STORY MUSGRAVE: Water is what we call neutral buoyancy, and it's not zero G. When I'm in space, I float inside the suit. It floats, I float. When I go upside down in the water tank, I'm not floating in my suit. I got 170 pounds of bearing resting on my collarbone; that's not good.

NARRATOR: In fact, doing anything in the heavy suit is hard, grueling work.

MIKE MASSIMINO: You can get tired; you're in the suit for about eight hours. There's no food in there with you, so you have to have a good breakfast. You do have a drink bag, so you can drink water while you're doing this, but you really need to be in the best shape you can be in.

NARRATOR: In stiff pressurized gloves, it's roughest on the hands.

JOHN MACE GRUNSFELD: We've had astronauts losing fingernails, you know: black and blue, and the fingernails fall off after a few days. You know, the fact of the matter is, the glove rules.

NARRATOR: After seven hours, the practice is over. Today it took too long to get the work done.

MIKE MASSIMINO: All in all, it was a pretty good run, but we need to get better. And I think we will. I think next week we're going to run the same run again. I think we'll be better next week.

I just tethered to it, and I slid it, somehow, jammed it inside.

CHRISTY HANSEN: Well, did you feel comfortable with that?

MIKE MASSIMINO: I mean, it was fine, as long as it don't come off when I'm not looking.

NARRATOR: Helping the spacewalkers get better and faster is the job of their instructors, Tomas Gonzalez and Christy Hansen.

CHRISTY HANSEN: We're their coaches, their teachers, their flight controllers and their friends. And we write all of the procedures for the spacewalks.

TOMAS GONZALEZ-TORRES: Do I hand you a tool now? Do I hand you a tool later? Do I put it on the stanchion? Do I temp stow it?

CHRISTY HANSEN: I'm on my way to the aft fixture.

NARRATOR: It's what they call choreography, and it's all about time.

CHRISTY HANSEN: We'll break torque on the A latch, and then completely remove wide field from the WSIPE...

TOMAS GONZALEZ-TORRES: Okay.

CHRISTY HANSEN: ...and start maneuvering up to the installation position up at the telescope.

TOMAS GONZALEZ-TORRES: Okay.

All of those things add up to seconds and minutes, and those minutes add up quickly to 10, to 15, to 30 minutes. And the choreography is what either makes you or breaks you.

NARRATOR: For the next two years, the choreography will be the center of their lives. No ballet is more exquisitely planned or painstakingly rehearsed. They'll write and rewrite the script, trying out ideas, debating what works best, changing, practicing again and again, to the point of exhaustion, all with one goal: perfection. Days are long; tempers flare. But after two years, they've got a timeline that's as crisp, tight and precise as they can make it.

Yet despite all the preparation, no one can be certain how things will go when they get to Hubble.

TOMAS GONZALEZ-TORRES: Things will go wrong on orbit. They always do, you know. It's our preparation for those things that will allow us to do a good job.

NASA SPACE SHUTTLE MISSION CONTROL: Good morning, Atlantis.

CREW ABOARD ATLANTIS: Good morning, Houston.

NARRATOR: It's Day 4 on orbit. The first spacewalk is about to begin.

MIKE MASSIMINO: Drew, this is your first spacewalk. What do you feel? What do you think?

DREW FEUSTAL: I'm excited.

MIKE MASSIMINO: Yeah, I can tell, man. You're ready to go. You're going to do great.

DREW FEUSTAL: I'm ready. Thanks, Mike.

MIKE MASSIMINO: Awesome, man. And John, this is, like, spacewalk number... 714?

JOHN MACE GRUNSFELD: Six.

MIKE MASSIMINO: Six, okay, great.

JOHN MACE GRUNSFELD: Ready, Drew?

DREW FEUSTAL: Ready, John.

JOHN MACE GRUNSFELD: Let's go do this.

Oh, this is fantastic!

NARRATOR: Drew and John's first task is the number one science priority for the mission: install a much more powerful wide field camera.

They'll loosen one bolt, remove the old camera, insert the new camera, and re-tighten the bolt. It's one of the simplest jobs on the entire mission.

But, early on, there's a big problem. When Drew tries to loosen the bolt holding in the old camera, it refuses to budge.

DREW FEUSTAL: No turning.

NARRATOR: If Drew can't get this bolt loose, the first job on the first spacewalk will grind to a halt.

JOHN MACE GRUNSFELD: Mass, the M.T.L. is slipping.

NARRATOR: The only people who can solve this are the ones outside with their hands on Hubble: John and Drew. Yet they're not alone.

A spacewalker with a problem has a vast network supporting him: five astronauts inside the shuttle, Tomas Gonzalez and Christy Hansen in Mission Control, and behind them, engineers who know Hubble better than anyone else on the planet.

MARK JAROSZ: We know the telescope; we know what hardware is broken. We know what the interfaces are...we need a flathead screwdriver or a certain kind of wrench or whatever.

NARRATOR: Now, as Drew struggles to loosen a stuck bolt, engineers call up all the information they have on that bolt, starting with its torque: the turning force needed to loosen it.

MATT ASHMORE (Hubble Tool Engineer): Every single screw is installed with a specific torque value. And there's paperwork that goes back that we can see what torque value was actually applied to that fastener.

NARRATOR: To make sure Drew can't over-torque the bolt, his wrench has a torque limiter on it called the M.T.L. When it reaches the limit, the M.T.L. will slip, to protect the bolt from breaking.

DREW FEUSTAL: Mass, I put in three attempts, got three M.T.L. slips, and see no motion on the A-latch bolt.

NARRATOR: The only option now: get rid of the torque limiter.

MIKE MASSIMINO: Try it without a M.T.L. at all.

DREW FEUSTAL: What are the implications if I over-torque and break the bolt?

MIKE MASSIMINO: You sure you want to know?

NARRATOR: If Drew breaks the bolt, the old instrument will never come out; Hubble will be stuck with an obsolete digital camera. The new state-of-the-art wide field camera will return to Earth unused.

JOHN MACE GRUNSFELD: My heart was absolutely as low as it could be; the potential of Wide Field Camera 3 for discoveries, you know, was slipping away.

DREW FEUSTAL: All I could do was apply the best technique that I could.

Okay, here we go. I think I got it!

JOHN MACE GRUNSFELD: It turned; it definitely turned.

MARK JAROSZ: Yes!

NASA SPACE SHUTTLE MISSION CONTROL: Houston for E.V.A., we copied and saw that. That's great news.

LISA HARDAWAY (Ball Aerospace & Technologies Corporation): My heart's still pounding!

DAVE LECKRONE: ...almost lost it, just almost lost it.

NASA SPACE SHUTTLE MISSION CONTROL: And the Wide Field Planetary Camera 2 is clear of the structure of the telescope.

MEGAN MCARTHUR: Hurray!

MIKE MASSIMINO: That's awesome news, Dan.

DREW FEUSTAL: When you're cranking on a bolt, whether it's in your garage or in space, it's either going to break or it's going to come loose.

NARRATOR: In the end, John and Drew get the powerful new camera installed, but the close call was almost a tragic loss for science.

NASA SPACE SHUTTLE MISSION CONTROL: Good morning, Atlantis. And a special good morning to you today, Mike Good.

NARRATOR: The next day, spacewalk number two: Mike Massimino and Mike Good have the awkward task of replacing the difficult-to-reach gyros.

The first replacement goes without a hitch, but they have trouble getting the second and third units to fit.

NASA SPACE SHUTTLE MISSION CONTROL: Crew members are an hour and a half behind the timeline at this point.

NARRATOR: They have to get those gyros in; there's no way to point the Hubble without them.

MIKE MASSIMINO: What was scaring me there, with the gyros, if we didn't get them changed out, you know, the telescope won't work.

NARRATOR: Eventually, they get the third unit replaced.

ED REZAC (Goddard Space Flight Center): We've got all three units installed, and...which is exactly where we wanted to be.

NARRATOR: No one's sure why the new gyros didn't fit; they're manufactured to precise tolerances. But it's not the first time that a tiny fraction of an inch has meant the difference between life and death for the Hubble space telescope.

In 1990, when Hubble was launched, astronomers discovered it was out of focus: the mirror was off by 1/50th the thickness of a sheet of paper.

ED WEILER (NASA Science Mission Directorate): Hubble was trumped up, it was going to be the greatest thing since sliced bread, and within a few months we suddenly became a huge joke in America. There were cartoons with Mr. Magoo as the true inventor of the Hubble space telescope.

NARRATOR: In 1993, astronauts went to Hubble and installed corrective optics to compensate for the mirror problem. After the first repair, Hubble began to realize its potential. Astronauts serviced it again in 1997, 1999, 2002. And the discoveries just kept coming.

MATT MOUNTAIN: The astronauts have been back, now, four times, and this has given Hubble its unique power compared to any other telescope in history.

NARRATOR: A fifth servicing mission was in the works, but after the 2003 Columbia disaster, NASA Administrator Sean O'Keefe cancelled it as too risky. Hubble would be allowed to die.

MATT MOUNTAIN: There was this uproar from the public, not just the astronomy community. I mean, school kids wrote in to NASA, sending in their school money to have it serviced.

NARRATOR: Then in April, 2005, NASA gets a new administrator who's determined to revive Hubble: Michael Griffin.

MICHAEL GRIFFIN (NASA Administrator, Retired): I'm an engineer, okay? I understand what the risks are. How do I change "not safe" into "safe?" And so we looked at that.

NARRATOR: The danger with Hubble is its orbit. All other missions go to the International Space Station; if one of those shuttles got damaged, astronauts could wait at the station for rescue.

CHUCK SHAW: For Hubble, you don't have that. We can't get to the space station. We're in a different orbit and a different altitude.

NARRATOR: The only way to rescue astronauts stranded at Hubble would be to have a second shuttle ready to launch at a moment's notice, something NASA isn't sure can be done.

MICHAEL GRIFFIN: The launch teams have to be able to process two vehicles. It's not a trivial matter.

NARRATOR: After 18 months of hard study, in October, 2006, Mike Griffin announces his decision.

MICHAEL GRIFFIN (Press Conference): We are going to add a shuttle servicing mission to the Hubble space telescope.

NARRATOR: But the rescue plan is a hair-raising scenario. If Atlantis is damaged on the way to Hubble, a second shuttle, Endeavour, will follow. Using its robotic arm, Endeavour grabs ahold of Atlantis. Once the two shuttles are in position, the Atlantis astronauts pull themselves along a rope to Endeavour, which brings everyone home.

It's never been done, and no one's sure it could work.

SCOTT ALTMAN: Now, not every answer is perfect, but it's a road that I feel comfortable we could go down. And it would give me an out.

NARRATOR: It's October, 2006, when the mission is revived—a costly delay. Three out of six gyros have died; batteries are getting old; and two science instruments have stopped working: one, a spectrograph called STIS, which splits light like a prism—STIS had been learning the chemical makeup of atmospheres of planets far beyond our solar system—and the other, the Advanced Camera for Surveys, which had been taking 70 percent of Hubble's images. Half of Hubble's science instruments, dead.

KEN SEMBACH (Hubble Project Scientist, Space Telescope Science Institute): It's like a symphony. Suddenly the woodwinds drop out; you know, the music's still beautiful, but it's not as full or as complete as it would have been if that other piece had been there.

NARRATOR: Normally, astronauts would install new instruments.

MIKE MASSIMINO: Generally what we do is we come up with a whole replacement for an instrument or for a piece of equipment. And even if something little is wrong with it, you don't mess with it, usually. You just pull it out and put the whole new one in.

NARRATOR: But no replacements exist; it would take too long to design and build them. The only hope is to try repairs in space, something no one's ever done before.

The spectrograph repair involves removing 117 tiny screws, then a cover, then replacing an electronic circuit board.

MIKE MASSIMINO: At first, it sounded like this would be impossible.

NARRATOR: So how do you remove 117 tiny screws that are weightless, while wearing clumsy gloves, and guarantee that not one floats into the telescope?

You start by going to the Goddard Space Flight Center, in Maryland, home of some of the best engineers in the world.

Goddard engineers monitor and control Hubble, 24/7. In the world's largest clean room, they test and maintain all the new parts and instruments waiting to go to the telescope. And they create remarkable new tools to fix Hubble.

It's one of those tools they hope will make the spectrograph repair possible by containing all the loose screws: the Fastener Capture Plate.

JOHN MACE GRUNSFELD: Which is, basically, a panel that has holes in that you can put a screwdriver through...

MIKE MASSIMINO: ...but small enough so that nothing will come out.

JOHN MACE GRUNSFELD: And as a result we can remove all those screws—they'll float around, but we won't lose any—and then we can take the cover plate off.

NARRATOR: The Fastener Capture Plate will attach to the spectrograph cover. As screws are removed, they'll float between the tool and the cover. When the tool is pulled off, the cover comes with it, with the screws trapped inside.

But they'll still need a tool to undo all those tiny screws in the first place.

The standard for turning bolts is the Pistol Grip Tool. Used on every Hubble mission, it's a power tool and a computer. It counts turns and remembers how much torque was used, preserving a record of every spacewalk for future reference.

But it's the opposite of what they need for the spectrograph repair: strong, slow and bulky.

MATT ASHMORE: You've got the computer sitting on top of the tool; you can't see what's in front of the tool. We needed something that could actuate those tiny screws quickly and delicately. And that's what led from the Pistol Grip Tool, to the birth of the Mini Power Tool.

How do we maximize the visibility of our worksite? We want the astronaut to be able to put that tool up on the screw and clearly see a bit going into that screw to know that he's

in the right spot. And it just logically followed that, "Hey, why don't we just put a headlight on the front of that?"

NARRATOR: The Mini Power Tool is just one of over a hundred new tools the Goddard engineers will design for this flight. To find out how they'll perform in space, they're tested at the pool.

The team begins arriving at dawn. Some of the Goddard engineers will dive so they can study their tools in action. Today they'll practice the spectrograph repair.

It's not only spacewalkers who practice; this is a full dress rehearsal for the entire team. Spacewalkers are in the pool; everyone else is up in the control room.

In the front row: astronauts. For the real mission, they'll be inside the shuttle, operating the robotic arm and helping the spacewalkers.

Next to them: instructors Tomas and Christy. During the actual flight, Tomas will be the astronauts' point of contact in Mission Control. Christy will be in a nearby support room, backing him up.

Behind them: the Goddard engineers. Today they're taking notes on how their tools perform. For the real mission, they'll be in a Houston support room, standing by to problem-solve.

As the practice repair begins, one of Massimino's first jobs is to remove a yellow handrail—undo four bolts and it's off.

Next, he'll screw in four posts called guide studs, one at each corner. The Fastener Capture Plate will mount onto these.

MIKE MASSIMINO: Why don't we try the other one?

DREW FEUSTAL: Mass, is there a two-handed technique that you could try, going in?

NARRATOR: Something's wrong; the guide studs won't tighten properly.

MIKE MASSIMINO: They're just not working today.

CHRISTY HANSEN: These same studs went in fine during the STIS class the other day, so you think there's something different about this instrument in the water?

MIKE MASSIMINO: I don't know.

TOMAS GONZALEZ-TORRES: Anybody know, for the Fastener Capture Plate to be seated properly, do we have to have all four...

ENGINEER: You need three.

TOMAS GONZALEZ-TORRES: Three?

CHRISTY HANSEN: Three? I don't think we should spend any more time on the guide studs.

TOMAS GONZALEZ-TORRES: I'm just worried the whole thing's going to fall apart when we start driving fasteners.

NARRATOR: They're not sure why the studs aren't holding, and there's nothing they can do about it now. But in space, loose guide studs could stop the repair in its tracks.

DREW FEUSTAL: So what are we going to do for today? What do you want to do with that?

MIKE MASSIMINO: You want to play it like we're in space. I'll fix it.

TOMAS GONZALEZ-TORRES: Okay, tell you what, let's press on.

NARRATOR: Continuing the job, Massimino installs the Fastener Capture Plate anyway, knowing it's too loose. Then: another problem.

MIKE MASSIMINO: Boy, you know a light would be really good on this tool.

NARRATOR: The light on Goddard's new Mini Power Tool won't turn on.

SCOTT ALTMAN: Well, it's not going quite as smoothly as I'd hoped. The tool, the light that would normally be on it isn't working; there's going to be a big debrief to discuss that. But it's not working as well as we had hoped.

NARRATOR: For now, a support diver will hold a flashlight. But there won't be any support divers in space. Inside the dark telescope, Massimino will need this light, and he's not shy about reminding the engineers.

MIKE MASSIMINO: If I can get a light on A-13, I bet I could see it.

That's where the light might help us.

Oh, you know, a light would be really good on this tool.

Am I making myself clear about the value of the light?

JOHN MACE GRUNSFELD: Hey, Mass, do you think a light would help?

MIKE MASSIMINO: Yeah, do you want to make that comment?

MEGAN MCARTHUR: Motion stopped.

NARRATOR: When Massimino finally gets the Fastener Capture Plate off and hands it to Mike Good, the bad news continues.

MIKE GOOD: We're losing screws out of this Fastener Capture Plate.

NARRATOR: In space, even one screw floating into Hubble could trash the telescope forever.

CHRISTY HANSEN: It gets frustrating, you see, if things don't go well. And we're stressed out, and the noise levels get high, and then you start to question yourself, you know, "Am I not doing it right?"

NARRATOR: Just about everything that could go wrong on the spectrograph repair did so.

MIKE MASSIMINO: The way I see it, there's a list of things you can screw up. And what you want to do is screw up, get...check off as many of that list as you can on the ground, so when you get to space, there's only a couple of them left.

TOMAS GONZALEZ-TORRES: For the Mini Power Tool, I think Mike missed the lights today, but I wasn't quite sure, so...

MIKE MASSIMINO: Sorry.

ENGINEER: Don't beat around the bush or anything.

TOMAS GONZALEZ-TORRES: Is there any way we can get the L.E.D.s fixed on the Mini Power Tool for Thursday?

MARK BEHNKE (Hubble Tool Engineer): Possibly you could replace the switch, so we're going to take a shot at that and see if that'll work.

MIKE MASSIMINO: You know, we've spent all this time and money and effort to do this. But if I can't see the fastener, it don't matter 'cause it ain't going to work. So my point was, is, out of all the stuff we're doing, the thing I really need is a light so I can see

what's going on. And if I can't, all this other work you're doing doesn't matter, 'cause I won't be able to undo the screw.

NARRATOR: Seven months until launch. It's been a long week.

CHRISTY HANSEN: Have a good weekend.

NARRATOR: But the Goddard engineers don't get a break. They'll spend the weekend trying to fix the Mini Power Tool.

MARK JAROSZ: So the stress is high, to get the tools modified and maximize the efficiency for these runs. So, yeah, the team's, team's pushing, they're pushing the limit a little bit.

NARRATOR: The next week, it's John's turn: the repair of the Advanced Camera, which had been taking most of Hubble's images.

Just like the spectrograph, fixing the Advanced Camera entails installing a Fastener Capture Plate and removing tiny screws, then a cover, then replacing circuit boards. The camera has fewer screws, only 32. But they're much harder to reach.

JOHN MACE GRUNSFELD: Because of the bulk of the space suit, I can't get in far enough really to see them straight on. So I'm going to be kind of working around a corner with the screwdriver.

Okay, I have the Fastener Capture Plate.

NARRATOR: The Goddard engineers have fixed the light on the Mini Power Tool. But ironically, the light itself now causes a new problem.

JOHN MACE GRUNSFELD: The reflection of the tool on the plastic is making it so I can't see if I'm in the screw head.

Yeah, it's just...looks like the teeth are rounded out.

MIKE GOOD: So the screw is stripped?

JOHN MACE GRUNSFELD: Yeah.

MIKE GOOD: Okay.

NARRATOR: A stripped screw. In space, this would be a huge problem, possibly ending the repair.

Another frustrating run is over. It's still not clear if these ambitious repairs are even possible.

DREW FEUSTAL: A little tiring, but the run came and went, you know?

JOHN MACE GRUNSFELD: It went miserably; we had all kinds of problems. The little crosses in the Phillips head, in the torque set, stripped out. And, you know, that's one of those disaster scenarios where then we're not going to get the cover plate off. So my confidence in this task is probably at its all-time low right now. But that's the way it goes.

NARRATOR: If these repairs are going to succeed, the tools will have to work flawlessly. And the astronauts will have to practice all the little physical movements until they become second nature.

STORY MUSGRAVE: You have to train the body how to do it. The mind alone is not enough; the body has got to know how to do that job.

NARRATOR: Seven months until launch. Every chance they get, the astronauts practice the STIS spectrograph and Advanced Camera repairs, training fingers, eyes, muscles, memorizing the delicate touch they'll need to manipulate tiny screws.

The engineers race to perfect the tools, repairing, testing, redesigning. No one has ever done repairs like this in space, and no one's sure they'll work.

MATT MOUNTAIN: This mission is one of the most complex they've ever undertaken. Changing the instruments, I think, all the astronauts can do, but to actually have to repair the STIS spectrograph and the Advanced Camera, that's going to be very challenging.

NASA SPACE SHUTTLE MISSION CONTROL: Good morning, Atlantis. And a special good morning to you today, John.

NARRATOR: It's now Day 6 of the mission. Spacewalk number three is about to begin.

DREW FEUSTAL: It's been a day of surprises each day.

JOHN MACE GRUNSFELD: We're prepared for the unexpected.

NARRATOR: So far, the unexpected has been the norm: they've had two difficult spacewalks. Plagued by a stuck bolt on number one, and troublesome gyros on number two, both ran long.

MIKE MASSIMINO: In baseball terms, you had two drag-out, long, extra-inning games. You know, you're a little worried, you got behind, you know things weren't working that great. And, so what you'd really like is a nice easy win.

NARRATOR: But an easy win today is not likely. Spacewalk number three includes the hardest job of the entire mission: repairing the Advanced Camera.

RAY J JOHNSON: How tired are we now? You know, how beat are we? This has already been a struggle, and A.C.S. on day three? I felt like, did we have enough practice at this one?

NASA SPACE SHUTTLE MISSION CONTROL: The second and final planned task for this spacewalk...

NARRATOR: Now, the task that's been the focus of John's life for months: the Advanced Camera.

NASA SPACE SHUTTLE MISSION CONTROL: Three hours, twenty-eight minutes into the spacewalk: a very intricate procedure to swap out some electrical cards.

JOHN MACE GRUNSFELD: I floated up to, kind of, see what my workspace looked like, and immediately it didn't look like the Goddard simulator or the N.B.L., because there was a black composite strut that was blocking the access to this electronics box. And I just thought, "This is going to be a big problem."

NARRATOR: If anything interferes with those circuit cards coming out, the repair will be over before it starts.

MIKE GOOD: Drew, the Fastener Capture Plate will be next from you.

NARRATOR: But first, John has to remove those 32 screws. That goes well.

NASA SPACE SHUTTLE MISSION CONTROL: The Fastener Capture Plate now removed, having done its job of capturing the 32 tiny screws.

NARRATOR: So far, so good. Not one screw stripped or lost. Now, the moment of truth: pulling out the cards.

ENGINEER: Alright!

JOHN MACE GRUNSFELD: Card one is out.

MIKE GOOD: Nice!

JOHN MACE GRUNSFELD: Woo hoo! Oh, that's unbelievable!

NASA SPACE SHUTTLE MISSION CONTROL: You guys are at least 40 minutes ahead on the timeline here.

MIKE GOOD: Nice!

JOHN MACE GRUNSFELD: I heard that.

There was that moment where the last connection was made; it was sort of like a magic trick. You know, click and poof: it's done.

RAY J JOHNSON: There's a video of John flying through the hatch, you know, with just the hugest smile on his face.

SCOTT ALTMAN: A task that we thought would take two days to get done, actually got done in one spacewalk and our shortest one to date.

RAY J JOHNSON: We needed that shot in the arm.

NARRATOR: The Goddard engineers who designed the tools and planned the repair are ecstatic.

ED REZAC: It was a good one today.

MARK JAROSZ: No issues, ahead of the timeline, went smooth, just like they practiced it.

NARRATOR: The next day, it's Mike Massimino's turn: trying to repair the STIS spectrograph.

He'll have to install the Fastener Capture Plate, remove over a hundred tiny screws, take off the Plate, then replace an electronics card.

But before he can get started, first he has to remove a handrail that's in the way. Four bolts and it pops off; he's practiced it scores of times.

NASA SPACE SHUTTLE MISSION CONTROL: That handrail is obstructing the attachment of the Fastener Capture Plate.

SCOTT ALTMAN: This initial task, the one that had been almost trivial in every prep—zip, zip, zip, zip—one of the bolts was completely messed up.

NARRATOR: The power tool spins and nothing happens. The head of the last bolt is stripped; it's not coming out.

This isn't one of the 100-plus tiny screws, it's a large, accessible bolt. In years of practice, it's never been a problem before. But now they can't continue. The entire repair depends on getting that handrail off.

SCOTT ALTMAN: If we are stopped here, it's over.

NARRATOR: Mike Massimino has spent two years of his life preparing for this repair. Now, it's all going doing down the drain.

MIKE MASSIMINO: It was unthinkable. I could not believe what was happen...I was ready to wake up from the nightmare. I was praying that I had imagined this whole thing happening.

DREW FEUSTEL: That darned handrail!

The atmosphere in the cabin was really getting gloomy for us, and I know it was getting gloomy for him out there.

JOHN MACE GRUNSFELD: We were at three-plus hours, at this point, which is quite late, because the handrail is really the start of the task, not the end. We could come up with problems all the way through.

NARRATOR: The Goddard engineers are brainstorming, trying frantically to come up with a workaround.

ERIC FOSTER (Goddard Space Flight Center): We have a database of 170,000 photos we can tap into.

NARRATOR: In the meantime, Mission Control orders Massimino to go fetch backup tools, anything and everything that might come in handy.

NASA SPACE SHUTTLE MISSION CONTROL: ...the vise-grips, we think that'd be useful...

RAY J JOHNSON: And then they started mentioning these tools I'd never heard, and Mass was going to get them, and it was like, "a tape dispenser." It was like, "What?" You know, I didn't even get that.

MIKE MASSIMINO: They were making me get a vise-grip, and they were making me get tape. I couldn't believe they're making me get tape. 'Cause what are we going to use the tape for? What about staples and paper clips? You want me to get those too? We got those. It was like I was going to the stationery store.

NARRATOR: To retrieve the tools, Massimino has to go all the way forward. They're stored just outside the cabin window where Drew is watching.

DREW FEUSTEL: I could see his face, you know, and I could see that he was just about as low as he could get.

MIKE MASSIMINO: Neither of us, I think, wanted to say anything out loud, so people would hear us, but we could see each other very clearly.

DREW FEUSTEL: Immediately I started smiling and looking back at him, saying, you know, "It's going to be okay."

MIKE MASSIMINO: He might have been lying, I don't know. But he was just smiling and giving me a thumbs up, and "What are you worried about? It's going to be fine."

He's looking down at me through the window, and, "We're going to be fine, you know. We're going to be okay. It's okay. We're going to be alright. We can get through this."

NARRATOR: While Massimino gathers backup tools, down on the ground the Goddard engineers have a radical idea: what about breaking the handrail?

RAY J JOHNSON: That's not something we do in space, you know? We just don't break things off. There's all sorts of, you know, hazards to this, you know? Cut edges and, you know, the handle goes flying. I mean, you just do the math. It's, it can, it's all fraught with danger.

NARRATOR: But could Massimino do it? Goddard engineers quickly perform a test, documented on a cell phone.

The test shows how dangerous it could be, but it is doable.

MIKE MASSIMINO: Once I heard that, I knew that I could do it, you know? So I liked that idea.

DREW FEUSTEL: It was like, "Oh, yeah. That's the easy answer." You know, just get back there and rip that thing off, and let's, let's get on with it.

NARRATOR: But will the handrail snap back and shatter Massimino's faceplate or tear open his suit?

DREW FEUSTEL: Houston, you ready for this?

NASA SPACE SHUTTLE MISSION CONTROL: Yeah, we're ready.

DREW FEUSTEL: Okay Mass, you have a "go."

MIKE MASSIMINO: Here we go.

It's off!

I was so grateful that the handrail came off, I felt like I was back in control, that it didn't matter what else would happen after that, we were going to get the thing fixed.

Disposal bag please.

The handrail was the mountain.

NARRATOR: With the mountain out of the way, the repair of the spectrograph is back on track. It ends up going eight hours and two minutes, one of the longest spacewalks in NASA history. But they get the job done.

The next day, John and Drew finish the remaining tasks of the mission.

NASA SPACE SHUTTLE MISSION CONTROL: The final spacewalk to service the Hubble space telescope is complete.

NARRATOR: Before John comes in for the last time, he has one more item on his personal checklist.

JOHN MACE GRUNSFELD: I grabbed the handrail and then let go and gave Hubble a little tap and a salute, and, internally, said goodbye to Hubble.

NARRATOR: The day after the final spacewalk, Hubble is released back into its own orbit. It's the last time humans will ever touch or see this magnificent telescope.

MIKE MASSIMINO: What were you thinking when you patted Hubble goodbye?

JOHN MACE GRUNSFELD: "Happy voyages. I hope everything that we did worked."

NARRATOR: It will be months before anyone knows if it did. The new instruments must get acclimated to the conditions of space. Whatever the outcome, this mission has set a new precedent for the kind of work possible on spacewalks.

MATT MOUNTAIN: They've pulled out boards, replaced boards, struggled with, you know, handles that wouldn't come off, and improvised. I mean, I think we have raised the bar enormously, because suddenly you can see what humans can do in space.

NARRATOR: As Hubble begins the final leg of its journey, the world waits for the results of the repairs. And no one is more anxious than the team responsible.

In September, the answer comes: stunning new images. Taken by the new Wide Field Camera, what masquerades as a beautiful butterfly is actually the violent fury of a dying star. The wings are gas streaming out at half a million miles an hour.

Another image shows a distant cluster of stars. The new camera reveals it as 100,000 suns; different colors show their temperatures and ages.

Still another captures a cloud of dust and gas, hiding fledgling stars within it. When the same camera shifts to infrared, the infant stars are revealed. Never before has a single instrument been able to detect such a broad range of starlight.

The stunning new camera, a spectrograph ten times more sensitive than any before, and two dead instruments, revived; Hubble is reborn.

MATT MOUNTAIN: It's been a stunning success. We've now got two new instruments, two repaired instruments, new batteries, new thermal blankets, new gyros, new guidance sensors; we have a new telescope!

NARRATOR: As scientists begin their work, the servicing team moves on. The engineers and astronauts who saved Hubble will now become like the rest of us, mere spectators, awed and moved by the wonders Hubble reveals.

MIKE MASSIMINO: You don't have to be a hardcore astronomer to appreciate what the telescope does. And whether it's in the form of a calendar or a book cover or a picture someone might see on someone's wall, it brings those images to everybody.

JOHN MACE GRUNSFELD: It's phenomenal that we have a tool in our lifetime, only four hundred years after the first astronomical use of the telescope, that we're answering all these questions and discovering all these new things.

SCOTT ALTMAN: I think there will be a moment, 20 years from now, looking back and thinking, "We really did that." And these things that we've learned are because the team across the country, everyone that became our extended family, made it happen. And I think I'll enjoy that.

NARRATOR: On NOVA's Hubble's Amazing Rescue Web site, follow producer Rush DeNooyer's dispatches about the repair as it was happening. See a Q&A with two of the Hubble astronauts, and more. Find it on pbs.org.

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