Preflight
Interview: John Grunsfeld The
STS-109 Crew Interviews with John Grunsfeld, mission specialist. I
thank you for joining us for this interview. I'd like to start off
by asking a little bit about your background. Why an astronaut?
Why become an astronaut?
I grew up on
the south side of Chicago. And, there were a lot of interesting
things going on in the early Sixties; and one of which was the human
space program was taking off; literally. It was also a time where
my family and others were able to buy televisions. And so, there
was kind of an interesting coincidence that at just the time that
I was very impressionable, televisions were becoming prevalent in
homes, and the space program was taking off. All of this came together,
and I was able to witness what I consider the most remarkable period
in American history: the start of the space age. And so, at that
time I kind of changed my mind from wanting to be a heavy truck
driver to being an astronaut. So, I've really wanted to be an astronaut
my whole life and go out and explore space.
Can
you talk a little bit, briefly, about the academic and career path
that you've taken to get to be an astronaut?
I've always
been a curious person. I was a curious little boy. My mom used to
associate me with Curious George, the monkey. And, I love to explore
things and find out how things work. And, that took me through a
young career in science. Even through grade school and high school,
I was always learning science. And, when it came time to choose
a major, I chose physics because it seemed to me that through physics
you can figure out how everything works, even the universe. I went
off to college, got a degree in physics doing astrophysics, and
then also graduate school doing astrophysics. Trying to figure out
what makes the universe tick.
You've
had a lot of experiences since becoming an astronaut. But is there
one most memorable experience?
I've had three
flights so far. This will be my fourth. I was incredibly lucky on
my first flight to be on an astronomy flight, where we were able
to do 24-hours-a-day, I worked 12-hour shifts with Tammy Jernigan
and the rest of the crew doing astronomy. And, for me it was a transition
from being a professional astronomer at a research institution to
being a professional astronomer in space. So, that was outstanding!
But, really the highlight of my career as an astronaut so far really
is the moment that…after Steve Smith and myself on the last
Hubble mission (STS-103) had fixed Hubble and closed everything
up that, you know, I kind of gave my last touch to Hubble before
going back in the airlock. And then, on Christmas day of 1999, we
deployed it. And, I think those moments around deploying the Hubble,
a working Hubble, is really the most memorable for me. The most
exciting and a little bit bittersweet because I thought, you know,
"Hmm, this might be the last time I ever see Hubble!"
And, so I'm really looking forward to going back up.
When
all is said and done and the STS-109 is done servicing Hubble on
this mission, what impact do you think it's going to have on you
personally and professionally?
Servicing the
Hubble space telescope is by far and away the most meaningful thing
I've ever done in my whole life. People have to decide for themselves
what kind of things they want to do and what it's worth risking.
And for me, working on the Hubble is worth risking my life for.
It's that important. It's just an incredible worldwide resource,
the Hubble. It's teaching us so much about our world, about the
universe, about who we are and our place in the cosmos. I mean,
there aren't any more fundamental questions than that. And so, going
up to the Hubble, bringing up an incredible new scientific instrument,
making the Hubble that much better, and also setting the stage for
a very long life for the Hubble space telescope. That's something
that is, I think, the most important part of this mission for me.
Has
Hubble been like a good friend to you?
Over the last
couple of missions, getting to know Hubble has been like getting
to know a good friend. And, astronomers have a relationship with
telescopes that they work on. I've had the privilege of working
on the 60-inch telescope at Mt. Palomar, and I consider that telescope
kind of a friend. All the late nights that I've spent up with it,
nursing it, keeping it working. And, the Hubble is kind of like
that for me, too.
Do
you recall the first time you saw a celestial body through a telescope?
If so, what was it? And describe what you were feeling at that point.
When I was
a relatively young boy, my grandmother gave me a small telescope.
And, it was a Sears Roebuck telescope. I don't even know if Sears
makes telescopes anymore. But, it was for me just an incredible
little machine. And, the first thing that I pointed it at was the
Moon. I really like the Moon. I've always felt a kinship to the
Moon. When I was driving around on family trips, looking up at the
Moon. That was the first thing that I explored.
Can
you talk a little bit about, on STS-103, the condition you found
Hubble in when the crew arrived there? And the tone that set for
that mission? And, compare that to how you expect to find Hubble
this time. Just contrast it, I guess.
Prior to STS-103,
the last Hubble mission, we had a number of briefings from the folks
at Goddard Space Flight Center from the contamination group that
we should expect Hubble to be in rough shape. That the atmospheric
oxygen, of course Hubble's traveling around at 17,500 miles an hour,
getting smashed by oxygen; solar particles are constantly hitting
it. These are cosmic rays from the Sun at high energy. Ultraviolet
radiation from the Sun. It's a really harsh environment up there.
And so, we were led to expect possibly that the insulation on the
outside of Hubble would be very degraded and peeling off. They found
a little bit of that on STS-82, so it was expected it would be much
worse on 103. We were told the solar arrays might be warped a little
bit more, and that the…even little things like the paint on
the handrails might be peeling off. So, we went up on STS-103 in
1999 armed with tools to cover handrails and to repair insulation.
And, what we found was that it was in almost the same shape as it
was on STS-82. That all of the damage that occurred had pretty much
happened kind of, you know, through its infancy; and that the telescope
was really in remarkably good shape. The outside of the telescope
was, you know, still pretty nice. The patches that they put in place
on STS-82 were still in place. And, the handrails were uniformly
in good shape. So, I'm expecting on STS-109 to find the telescope
just as we left it on that mission in December 1999.
Is
it sort of a testament, I guess, to the ground support people, and
to the STS-103 crew that a mission of that nature was…they were
able to put it together so quickly? And for the crew to get things
done as well as they did?
The situation
we had on STS-103 was an interesting one. Because we started training
quite a while before the flight that we were supposed to fly which
was servicing mission 3. And so, we were pretty fully trained or
well on our way to being fully trained for that mission when the
gyroscopes failed and we had to do kind of a crash course on gyroscopes
and, in 6 months, train for a mission that turned out to be very
different than what we had thought. So, for this mission, it's pretty
special because the things we had trained to do on the original
mission [are] what we're going to do on this mission. And, the same
team that put together that STS-103 mission to change out the gyros
in such a hurry are the same folks that are working this one. And,
the team is incredible! The folks at Goddard Space Flight Center
really know their stuff. They know how to work with us. They know
how we train. Sometimes I believe they even know how we think so
that they can get us prepared for these missions. And, the hardware
is absolutely top-notch! I consider these some of the best people
in the world in what they do.
Just
as a little backgrounder to the STS-109 mission and, I guess, a
little history about all of the servicing missions, can you talk
a little bit about why we even have Hubble in the first place? What
can Hubble do that some telescopes on the ground and some in orbit
can't do?
We have on
planet Earth a remarkable collection of telescopes on mountaintops
on remote islands. We have a whole family of telescopes on top of
the big island of Hawaii. And, mirrors keep getting bigger and bigger;
and the bigger a mirror you have, the better your resolving power.
The smaller the thing you can see and also the more light you collect;
just a big light bucket. But, there's a fundamental limit. The Earth's
atmosphere has a lot of little waves in it. And, they disturb the
light as it goes through; they distort it. So, [there are] some
things you just can't do from the surface of planet Earth if you
want to see very, very fine detail in very dim objects. And so,
I'm not really sure when it started, but Lyman Spitzer back in the
Seventies started pushing the idea that if we put a telescope with
a relatively large mirror in space we could get images that are
limited only by the optics of the telescope and not by the atmosphere.
So, that was probably the primary driver. The other driver is that
the Earth's atmosphere is really very kind to us. It protects us
from ultraviolet radiation from the Sun. And, the Sun is…produces
a lot of ultraviolet radiations. It would be very damaging to our
skin; we all know about the dangers of skin cancer and wearing Sun
protection; that Sun protection is to protect us from what little
UV gets through the atmosphere. Well, some of the most interesting
things in the cosmos occur in and produce light in that ultraviolet.
And so, if we want to study those things, we have to be above the
atmosphere. And so, we've flown two shuttle missions - ASTRO-1 and
ASTRO-2 - that were dedicated to ultraviolet astronomy. And the
Hubble space telescope, one of its great strengths is that it can
do ultraviolet astronomy because it's above the atmosphere. The
third thing you can do if you're above the atmosphere in Earth orbit
is: you don't worry about the fact that the Earth turns and that
sometimes it's daytime and you can't observe and sometimes it's
night and you can. Sometimes it's cloudy at night and you still
can't observe. (Every astronomer knows that frustration!) But, the
Hubble can look at one spot in the sky for days on end. And, that's
how we've made some of the remarkable discoveries in the deep field
that shows, you know, thousands of galaxies in an area that previously
was devoid of any known objects. So you can do many different things
in space that just aren't possible on the ground.
And,
we've recently gotten another gift from Hubble. It's studied the
atmosphere of a planet, an exosolar planet. How important is it
to have Hubble and telescopes like it that can see in different
wavelengths of light? And what does that do to give us a better
idea of the origins of the cosmos?
The instruments
on Hubble have a wide variety of capabilities. Some of them are
like cameras. They can take wonderful pictures. There's others like
the Space Telescope Imaging Spectrograph that has what's like a
prism. It can break the light up into its component colors. When
you're studying an image of something, you're trying to figure out,
you know, what is this thing? You know, what does it look like?
And some of the images are just simply beautiful which a lot of
folks appreciate. But, when you break the light up into its component
colors, you're starting to look into the physics of the object.
What temperature are the sodium atoms in the atmosphere of a planet,
for instance? You know, that's a very interesting question. And
this recent discovery of Hubble observing the atmosphere of a planet
around a star 150 light years away is one of those discoveries that
I don't think the original Hubble designers anticipated we would
use Hubble to do. At that time, no known planets were known outside
of our solar system. And, now we know of about 70 or so. It's one
of those incredible discoveries that shows, using Hubble, that we
can do incredible things. We can look at planets outside of our
solar system with these telescopes! And, it's a combination of space-
and ground-based telescopes that make these discoveries. Hubble
is really a partner in the grand investigation of astronomy that
we're doing.
As
Payload Commander, what will be your primary responsibility for
this mission?
The main part
of my job as Payload Commander on STS-109 occurs here on the ground.
My responsibilities are to make sure that Jim Newman, Rick Linnehan,
and Mike Massimino and myself, that we're trained to do the EVA
tasks; that the tools that we have that we're taking up with us
are the right tools and that they work; and that all of the equipment
in the payload bay is arranged in such a way that we can do our
job. I'm also prime for knowing all the Hubble systems. So, once
we've got Hubble and we've got it docked, then I can work with the
rest of the crew to make sure we keep Hubble happy while Hubble's
in the payload bay. Curt Brown, my commander on STS-103, called
Steve Smith, who at that time was the Payload Commander, the "EVA
Commander" because we don't really have a payload. Our payload's
already in orbit. We're going up to meet it. But we do have a lot
of tools we're bringing up, and those will help us do our job.
Are
there any new tools for this mission? Were there new ones?
We have some
specialized tools for this mission. We're doing, I think, about
100 connectors in one day for the PCU change out (that's the power
control unit). We've developed a special connector tool that gives
us a lot more holding power on the connectors, better mechanical
advantage. So we'll be using that quite extensively. There are a
number of other tools that are specialized, as every Hubble flight
has, for different tasks; for the solar array tasks, for the cooling
system. So, we'll be using those as well.
Can
you briefly, in a nutshell, explain the goals of the mission? And
we'll get into EVA deeper a little bit later. But just in a nutshell,
the goals of the mission and their benefit.
There are really
three main goals for this mission. And, they can be divided into
the Hubble power system. We're going to replace the solar arrays,
put in a new power control unit, some new diode boxes that go with
the solar arrays; and those improvements are specifically designed
to allow Hubble to have more capability to replace the current solar
arrays which were designed to be replaced (that was anticipated),
and to ensure that Hubble has a long and happy lifetime. [There
are] currently some relay failures in Hubble. They're mechanical
systems; that happens. And so, we're going to change out the boxes
that those relays are in and put the new solar arrays on. The big
thing about the new solar arrays is that they'll provide 30% more
power to the telescope. And, that'll allow us to operate as many
as four scientific instruments at the same time! Right now, you
know, we pretty much use one instrument: we use the wide-field camera
or we'll use the STIS. With these new power systems, we'll be able
to run the Advanced Camera for Surveys and the NICMOS (the infrared
camera) at the same time. So, that even further broadens Hubble's
capability over wide wavelengths. I mentioned the Advanced Camera
for Surveys. That's really for me the most important part of our
mission. We're going to bring up a camera that has ten times the
discovery power of the wide field camera, the Wide Field Planetary
Camera Two. That's a big difference. That's like going on a home
telescope from a 5-inch mirror to a 16-inch mirror! That's a big
change! That's buying a whole new telescope. If you went to NASA
Headquarters and said, "I have this idea where I can build
a telescope that's ten times more powerful than Hubble!" First
of all, they wouldn't believe you (because that's too big a deal),
and then they'd say, "Oh yeah, but it would cost many billions
of dollars." Well, just by putting in the Advanced Camera for
Survey, we're going to make Hubble in a sense ten times better.
And, so that's a very exciting part of the mission. The other third
part of the mission is that we're going to put a cooling system
in to bring the Near-Infrared Camera Multi-Object Spectrograph back.
And, that's something that I…a lot of scientists are very anxious
about because the cooling system that was originally launched with
that camera was supposed to last five years; it only lasted about
a year-and-a-half due to a thermal short. So they're very, very
happy to get that back.
As
you…if you could envision the mission unfolding before you,
which activities will be the biggest challenges for the crew?
A mission like
our mission, STS-109, has a number of challenges. And, the first
challenge is to go and rendezvous and capture Hubble. And even though
we've done that a number of times before and we rendezvous with
space station as well, any rendezvous with another spacecraft in
orbit is something not to be taken lightly. And, Scott Altman, Nancy
Currie, and Digger Carey (Duane Carey) are really the champions
of that. And so, they're…we're in good hands; and I have no
doubts that we'll do that successfully. But, it's still a challenging
part of the mission. Obviously we need to grapple Hubble with the
robotic arm; that's Nancy Currie's job, and berth it in the payload
bay before we can go out and do any space walking on the telescope.
Once we've done that, I think on this mission every space walk has
its challenges. These are perhaps the most difficult (or at least
close to the most difficult), EVA activities that we've ever done
in the Space Shuttle Program. And, it's not just one; we have five!
That being said, I think the third EVA is going to be the most challenging
from a couple of perspectives. One of which is: just the sheer number
of connectors. Before we can start changing out the Power Control
Unit (the PCU), we have to turn off the telescope and unplug the
batteries. So there's a bunch of connections involved in that. Then
once we're there, Rick has to disconnect 36 connectors on the PCU.
And, Mark Lee on STS-82 had to do a similar job on a different box;
and he said it's some of the hardest things he's ever done. He had
18 connectors to do. We'll change out the box. Then we have to put
all of those connections back: the 36 connections on the PCU, and
then six connections on the batteries, and a number of other interfaces.
So, it's going to be a very long, very tedious day. From a spectator
point-of-view, it's not that interesting. You know, it's going to
be Rick and myself at various points, up on the telescope, in the
electronics bays, which is just a small 3-by-5-foot door that will
be open and you'll see our backs. And, we'll be sitting there taking
off connectors. And so it's just going to be a challenge of human
performance. And also, how easy are the connectors to take off?
How hard? Well, we won't know until we get there. And so, we're
training that very hard. The other side of it is: that in 12 years,
Hubble has been running very nicely on orbit. It's had little problems
here and there. We've fixed things. We've serviced the telescope.
We've made it better. But, it's never been turned off before. And
so, for the first time in 12 years, you know, the world's greatest
telescope, an international resource, is going to be entirely turned
off. And, so I'm a little bit nervous that once we finish the job
and we go to turn it back on, that everything's going to come up
properly. All of the experts say that the, you know, they've analyzed
it. They've done tests. That it should come up nicely, but I know
I'll feel a lot better when, later that night, after we're back
inside, that we get the call from the ground that Hubble's up and
running again.
Obviously,
STS-103 gives you a big advantage in this mission. I mean, you've
been there. You've done it. Has that been the one that's prepared
you best for this mission?
WYeah, there's
no question that having done a Hubble servicing mission prepares
me for this mission in a great way. And, that's part of NASA's plan,
is to have somebody who has experience with Hubble on the next mission.
There's no guarantee that we can do that. But, that's been a very
effective strategy with Steve Smith from STS-82 being on STS-103;
and I think now myself from STS-103 going on STS-109. I bring that
experience of knowing the system, knowing the people, knowing how
Hubble works, and having experienced the EVAs and the character
(if you will) of doing space walks on Hubble. I've tried to then
carry that forward and teach that to my space walking buddies and
the rest of the crew. You know, what kind of things are different
on Hubble than you might find on space station or elsewhere.
Okay.
And, there's
a lot of value in that.
Future
plans for Hubble: what are they? And, what would you like to see
happen with Hubble in the future?
Hubble's future
is, I think, one that's a little bit uncertain. When the original
crafters of the Hubble program put together the shuttle support
plan, which are the servicing missions, they included one that's
a Hubble retrieval. It was believed that at the end of Hubble's
life, which would be I think two missions from now, we'd put Hubble
in the payload bay and bring it back home and, I presume, put it
up in the Smithsonian. From my personal perspective, I would much
rather have Hubble in orbit doing science than in the Smithsonian
for people to see. And, I think the incredible discoveries that
Hubble makes - not just once, you know, every five years; but it
seems like, you know, once every few months something comes from
Hubble that nobody expected and it's earthshaking - I think people
would rather have those discoveries than have Hubble in the Smithsonian.
So, there's a lot of discussion now about, "Well, what are
we really gong to do with Hubble at the end of life?" And,
the best thing that we could do is: as long as Hubble is doing well,
is continue to upgrade it and continue to keep it doing science.
There's a Next Generation Space Telescope that's being developed
by NASA. And, we think that roughly around 2010 that might be going
in orbit. So, I think the best thing that we could do with Hubble
is at least to keep it going so that it has a fair overlap with
Next Generation Space Telescope. That allows us to do simultaneous
observations and to make sure that the new telescope works well;
but also to do observations with Hubble that Next Generation Space
Telescope can't do. Ultraviolet observations. Some of the imaging.
Next Generation Space Telescope will be much more single-purpose.
Hubble is very general-purpose. It's kind of like when, on the ground,
a new 8-meter telescope, you know, the world's largest telescope,
comes on line. It can do things that Mt. Palomar at 200 inches could
never do. You know, now, you know, a 5-meter telescope is a relatively
small telescope. But, Mt. Palomar still is one of the world's greatest
telescopes. It's still a great telescope! It has a good site; and
many, many scientists, graduate students, astronomers use it every
night that's clear. And in the same way, it would be a shame, when
we have a new space telescope - Next Generation Space Telescope
- to decommission Hubble just because now we have two. So, I'm hoping
that we have additional servicing missions. I'd like to see at least
one more shuttle-based servicing mission added to provide the ability
to keep Hubble up for at least another decade. I think that would
be the best thing that we could do. It turns out now that you have
Hubble in space and that we've done these servicing missions, it's
a pretty good investment. For a small amount of money, like the
Advanced Camera for Surveys, we're making the telescope ten times
better. It would cost billions of dollars to put up a telescope
that good now, if you were to start from scratch. So, it's a shame
to turn Hubble off, you know, in just a few years.
Let's
talk a little bit about the EVAs if we can. --
I'm just going
to take a drink here.
Sure.
Go ahead. I may need one myself pretty soon. EVA-1, flight day 4.
You and Rick Linnehan will go out to start the series of five, possibly
six EVAs. (Hopefully just five.) Can you talk us through the timeline
of EVA-1? And highlight where the major activities will take place
on Hubble.
The first EVA
day I think will set the stage for all five of our space walks.
It's in the beginning of the EVA day, first of all I'll come out
of the airlock. And then, Rick Linnehan will come out of the airlock.
And for me that's very exciting; he's a classmate of mine. This
is his third flight but his first space walk. And so, I'll get to
see my friend and my space walking buddy come out of the airlock
for the first time on his first space walk. But, we won't have much
time to enjoy the view because this is a very busy day. This is
the day where we have to set up the payload bay. We've gotten to
orbit; we've grappled Hubble; put it on the servicing structure;
and now we have to go and get the payload bay and Hubble ready for
servicing. And, that involves a number of activities with putting
a special support post under the telescope to rigidize it (the BAPS
post). I'm going to put an antenna cover over a small, delicate
antenna at the bottom of the telescope so that we don't inadvertently
hit it. Rick is going to be setting up the shuttle robotic arm,
the robotic manipulator system, with a special foot-plate that we
can stand on and that holds our tools. So we'll both be very busy
right at, right from the start. That'll take about an hour or so.
Now from there, we move straight into the solar array change-out.
If all goes well, the solar arrays will be all rolled up; and we'll
go up on the telescope about halfway up; and we'll take off those
flexible arrays that are now rolled up, we'll take them off and
put them into the payload bay on the shuttle. And then, we'll take
out the new solar arrays. And, they're quite a bit different than
the old ones. Instead of being rolled up, they're actually rigid
arrays; and they open like a book. So, we're going to take these
roughly 9-foot-by-12-foot arrays out; and Rick is going to hold
on to the array; and Nancy Currie will lift Rick up out of the payload
bay, using the robotic arm, with a 640-pound solar array in front
of him. Rick is then going to steer it around towards the telescope,
and then together Rick and I will insert it into the fitting onto
Hubble. And then Rick is going to open up the solar array, like
a book, exposing it to sunlight. And, we'll cinch that down, clean
up a little bit of the payload bay, and come back in. There are
a few other little things that we're going to do. We're going to
wrap some cables in preparation for the next EVA day where we'll
put the second solar array on. And then, it's Jim Newman and Mike
Massimino's turn to essentially do the same thing on the other side
of the telescope.
And
for the second EVA, you and Rick will be inside, with IVA activities.
Can you talk a little bit about what you'll be doing inside?
On the first
EVA, Jim Newman will be the EVA choreographer; we call it the IV
crewmember. And, he really is the conductor for the whole EVA. Whatever
he says to do, we'll do. And, I, you know, I kind of think of him
back there like the conductor of an orchestra, you know. You know,
"Go ahead and smash the cymbals now," and all this kind
of thing. He'll also be working with Nancy to coordinate all of
the robotic manipulator system activities so that, you know, we
go to the right place at the right time. And, in the meantime, Mike
will be backing him up, providing him with data, you know, on what
interface torque is the correct torque; and things like that. Doing
anything that Jim needs to help him do his job: taking pictures.
On the second EVA day, I'll be the conductor for Mike and Jim. And,
while they're out there, I have the procedures in front of me; and
I'll be reading those to them and watching their activities, trying
to make sure they arrive at the right place at the right time. Very
much like an orchestra. And, that the EVA goes smoothly. Also, if
they come to some bolt, for instance, that won't turn when they
put their wrench on it, we have the procedures inside that I can
quickly flip to. And, Rick will be helping me on that. He'll be
backing me up so that if Mike goes to turn a bolt and it won't turn,
I can right away say, "Okay, the procedures say, you're allowed
to increase the torque by one notch on the tool" or "Put
that tool away and get out another one and maybe crank on it with
a hard wrench." Whatever the procedure says to do, we'll be
prepared to provide that to Mike and Jim so that, you know, we keep
the music playing.
And,
will your, you and Rick's, IVA, duties, vary any on the two IVA
days that you'll be inside?
For the second
EVA, I'll be the EVA conductor, IV crewmember. By the time we get
to the fourth EVA, Rick, now being a very experienced crewmember,
is going to take over the IVA reins as the lead IV and I'll back
Rick up. And then for EVA-5, Mike Massimino will be the lead IV.
EVA-3
- can you walk us through that scenario? Through the timeline again
highlighting where the main activity will take place.
Even while
Rick and myself are in the airlock on the EVA-3, the activity will
have already started. Up in the flight deck, Jim and Mike will have
started to work their steps on the avionics on Hubble, to start
powering it off. And, the folks on the ground are going to kick
off a procedure called the "super proc." You know, I imagine
that there's some guy at a computer console with a big "S"
on the shirt, you know, in a cape and his hands madly clicking on
the keys. Of course, it's not really like that. But, they're going
to send a large program up to Hubble to tell it to start turning
things off. Once we egress the airlock, Rick and I are in turbo
mode because we have to go out and there's various times that we
have to hit (gates, if you will) to get Hubble in position to change
out the power control unit. We have to get thermal covers on some
of the bays because, once Hubble's unpowered, space is a very cold
place; and it's going to start radiating to space, cooling off,
and some of the equipment can't get cold. It's just a limit on the
mechanical components, on electronic components. It's kind of like
if you live in Minnesota, where our pilot Duane Carey comes from,
you know, if you leave your car out at a restaurant, in the bitter
cold and come out and expect it to turn on, it may or may not turn
on. Hubble's the same way. We don't want it to get too cold. And
so, Rick and I are going to be speedily getting Hubble ready, to
change out the power control unit. And that, as I said, includes
putting some thermal covers on. Rick is going to start disconnecting
batteries. They're the same batteries that I worked on, on STS-103,
so we have a little bit of experience in that area. And then, Rick
is going to start disconnecting connectors on the Power Control
Unit, as soon as he can get there. We're going to try and stay ahead
of the power curve, so to speak, because this is an EVA that could
go long. There's so many unknowns in it, that it, if any of these
EVAs on our flight are going to be long ones, this would be the
one to look for. We're prepared if necessary to swap out roles if
it becomes too tedious. This is the kind of task that Mark Lee said
was very difficult, so we're preparing for that. So, while Rick
is disconnecting connectors, I'm going to be just by his side relaxing,
as if, you know, I'm sort of on deck, in a, you know, just keeping,
you know, warm but ready to go. If Rick gets tired, I'll jump in
his place and disconnect until we get all the connectors off. Then
we'll swap the PCU. It's about halfway up the telescope in a little
electronics bay. So, I'll take it out. Nancy will take me down to
meet Rick. In the payload bay, we'll change it out for the new box.
I'll put the new box in, and then start connecting. While I'm connecting
the connectors, Rick is going to be by my side relaxing. In case
I get too tired, he can jump in and take a few connectors. Right
now, Rick is disconnecting most of the connectors and then I'm connecting
the connectors. And, that's the plan; but we're ready for anything.
Okay.
And then, we'll
continue back undoing all the things that we did earlier by putting
the batteries back on line, taking thermal covers off. And once
we have the batteries back on line, you know, then the man with
the big S and the fast fingers is going to send commands up to start
Hubble systems back on.
And
will that…will turning the systems back on happen while you're
still outside? Or, in, back inside?
Unfortunately,
the way the plan works now: it's really easy to turn Hubble off.
You know, well, we hope. We hope it's really easy to turn everything
off. But, when we go to turn everything on, I think the ground is
going to be much more deliberate and careful, turning things on
one-at-a-time, checking it out, going to the next box, turning it
on, checking it out. So, it may take quite a while before we find
out that everything is back up and running again.
EVA-4
- can you talk a little bit about the timeline, about what's going
to happen, outside, with Mike and Jim? What will they be doing?
Where [will] they be doing it?
For EVA-4,
in some sense on this mission, we have the most experience. We're
changing out one of the axial scientific instruments. It means the
ones in the big part of the bottom of the telescope; there are four
scientific instrument bays where we can put refrigerator-size instruments.
And, we've done this on every one of the servicing missions except
STS-103. So, we have some experience doing that. Nevertheless, it's
kind of a tricky task. The scientific instruments have to be kind
of threaded into the telescope. And so, the first thing that they're
going to do is to take out the Faint Object Camera. And, this is
the last of the original scientific instruments. And, Jim Newman
will take that out and put it onto a special fixture hanging over
the left side of the space shuttle. And then, he and Mike will take
out the Advanced Camera for Surveys and put it into the telescope.
Once the Faint Object Camera is out, Mike has one of the best opportunities
of anybody on the crew because he gets to go inside the telescope,
and his whole body basically - he's a big guy, almost his whole
body, maybe his feet will be hanging out - he gets to go inside
the telescope and look around to make sure that there isn't any
insulation or tape or anything that's hanging in the way before
we put the Advanced Camera for Surveys in. And so, his head will
basically be, you know, at the heart, at the, you know, the soul
of Hubble because this is where all the light from the telescope
comes through into the scientific instruments. And, that's where
his head will be. The sad thing is the cover on the telescope will
be closed; so he won't actually be able to look up and, you know,
see galaxies or anything like that. But, you know, for me as an
astronomer, that would be a very exciting place to be.
Sure.
And, I was
pretty close last time. So, I've gotten to experience that when
we were working on the gyros. So Mike will get that view. Then in
a very tight choreography, Jim and Mike will slowly insert the Advanced
Camera for Surveys into the telescope. And then, Mike will first
drive one bolt; and Jim will drive another bolt. And, that will
lock the scientific instrument in place. And, that's when everybody
breathes easier, once both those special locks are in place. 'Cause
that's how Hubble registers the instrument, to make sure that it's
right in the optical path of the telescope. They'll hook up the
Advanced Camera for Surveys; and then after that, they'll do some
tasks that are cleaning up after the PCU day. There're a number
of things we do to get ready for the PCU ahead of the PCU day on
EVA-3; and then after we've completed the main tasks on EVA-4, they'll
continue the cleanup effort for the PCU. I think of the Power Control
Unit change-out as not really EVA-3 but EVAs -2, -3, and -4 because
Jim and Mike will do some prep work on EVA-2 (as we will on EVA-1
as well); and then the main change-out occurs on EVA-3; and then
on EVA-4, there's some cleanup.
And,
for EVA-5, you and Rick will be back outside to install the NCS
and the radiator. Can you talk us through that task? And, I understand
there's a bit of plumbing work to do.
Yup. This mission,
STS-109, is a little bit different than any of the previous Hubble
missions because we're doing a number of things that folks never
thought we would do on Hubble. Although they've talked about the
power control unit change-out before, I don't think anybody ever
thought we'd really do it. It's just too hard. But, the other thing
we're doing is: we're changing out the solar arrays with these rigid
arrays that will make the telescope look very different. They're
smaller; they're a different color; they're rigid. But, we're also,
on EVA day 5, putting on the cooling system. And so, we're going
to hang on handrails a large 12-foot-by-4-foot radiator on the outside
of the telescope. (Nobody ever thought we'd do anything like that.)
And, we're going to snake through the bottom of the telescope a
bunch of plumbing that contains electronic control lines but also
cooling lines. That's kind of like installing an external air conditioner
in a house for the first time. And, plumbing it through a hole in
the bottom of the telescope that was essentially a vent line previously.
So Rick and I are first going to open up the big doors on the bottom
of the telescope and we'll put in the cryo cooler (that's the refrigerator).
And it's a relatively large box that goes on the floor of the telescope
and clamps into handrails, again, that nobody ever thought would
be used for putting items. And, Rick will get that all plumbed up;
and we'll start some of the connections. Jim and Mike will have
fed through a large cable harness from the Advanced Camera for Surveys
side that's hooked up to the electronics for the cryo cooler. And
then, we'll hook up the rest of that. At that, while Rick's hooking
up all of the components on the inside of the telescope, a very
delicate area again (everything inside is a scientific instrument,
and he'll have to be very careful there), I'm going to go to the
back of the payload bay and start taking the bolts off of the radiator.
After that, Rick and I are going to switch places. I'll be on the
arm; Rick will become the free-floater. And, I'll go back and hold
on to the radiator, and Rick will undo the final latch. At which
point, Nancy will drive me out over the port wing, holding this
large 12-foot-long radiator. And I'll bring it around to the front
of the telescope and hang it on the handrails. And Rick and I together
will clamp it down. After that, Rick is going to climb underneath
the telescope and get into a foot restraint so that he's looking
straight up through this little hole (it's about that big) in the
bottom of the telescope. And, I'll swing the cables around and underneath
to him, and then he'll start feeding them up through the hole. I'll
go inside the telescope and start pulling it up. And, we'll try
and get this very, very long - I think it's ten feet or so of cable
- through the bottom of the telescope. And, we've trained this many
times in the pool; but nobody's done anything like this on Hubble.
Once it's through, we'll clamp down a little holder in the bottom
of the telescope that keeps any light from getting into the telescope
from the bottom; and so that'll still be dark inside the telescope.
(It's good to have no light inside the telescope from other than
the place where the mirror is.) And, we'll hook up all the connections
and close the doors.
Do
you remember when the mirror aberration was discovered and what
the mood was with the people close to the project?
The Hubble
project has been really a vision for a number of truly world-class
astronomers, starting with Lyman Spitzer and many others. And, it
was something that had a long and difficult road, just to get to
the point where we could launch it. It was originally supposed to
be launched in the late Eighties. We had the Challenger accident.
Many scientific experiments and observatories were held up. The
Hubble, of course, was launched and, you know, people basically
held their breath until the first images came out. And, the images
were really spectacular. But, they weren't as good as the scientists
had hoped. And it was very clear from the start that something was
terribly, terribly wrong. I think the whole astronomical community
was truly depressed at that point and looking for answers. You know,
"How could this happen?" And that didn't last very long
before people started asking, "How can we fix it?" And,
that shows the true strength of NASA and the astronomical community
that we all join together to figure out, "How can we fix it?"
And, on STS-61, we went up and fixed it. It was at that point I
think the public, having in some sense not really ignored the problems
- you know, people said, "Oh it's a terrible NASA problem.
How could this happen?" - but nobody knew how great Hubble
was going to be. So, I think if people knew how great Hubble was
really going to be, they would've been much more upset that the
mirror was flawed. That it had the wrong shape. So since STS-61,
we've seen how truly spectacular and earthshaking the discoveries
from Hubble are. I find it amazing how much public support. I mean,
it's far beyond what I really would've expected from the common
person on the street and for every American to be interested in
astronomy. But, as I go around the country, I find that kids and
adults, everybody really finds the things that Hubble is discovering
as fascinating. You know, ranging from, you know, planets around
nearby stars that we can now see--
Right.
-- five years
ago, we didn't even know that there were any planets outside of
our solar system. People suspected it; there're planets here; there
should be planets elsewhere. But, we didn't know. Now we know. Since
the dawn of time and people, we've always wondered what's the fate
of the universe. Well, Hubble's figuring that out (and other observatories).
But Hubble is…observations from Hubble are helping us figure
out what the shape of the universe is, how big it is, how old it
is. And, the remarkable thing is: we're discovering that not only
is the universe expanding from a Big Bang (that's been known for
a number of years); but for some reason, it seems to be accelerating.
And, the implication of that is that 60% of the energy in the universe
is made up of stuff and we have no idea what it is. So, for me it's
very exciting. And, I think [for] a lot of scientists it's very
exciting, when you learn that most of what you know about the universe
is that you don't know anything about the universe. Because it opens
up the door, potentially, for, you know, the ability maybe to travel
like Star Trek. Or, you know, all the exciting things that we dream
about in science fiction. Well, that science fiction is happening.
We're seeing it. With the addition of the Advanced Camera for Surveys,
I think the discovery space that we're opening up, leads me to the
belief that the next most incredible discovery the Hubble will make
is something that we can't even imagine now. So, the fact that we
fixed the mirror on STS-61, and have been making all these discoveries
with Hubble, I think, has really set the public and the astronaut
community firmly behind the Hubble space telescope as really a national
treasure and something that we can all enjoy.
And
maybe even in broader terms: has Hubble been somewhat responsible
for, maybe, the continuation of the space program, with the International
Space Station? If Hubble was not able to be fixed, where do you
think that would've… what impact would that have had on the
space program?
When we look
at all of the activities that NASA does, it's truly remarkable.
I mean, NASA's, of course, the first aim is aeronautics. You know,
we are responsible for helping industry to develop new airplanes
and faster, better, cleaner airplanes. In the space area, we have
a very strong space science program, a life science program at NASA
(because we're very interested in how people do in space, how we
survive, how can we do better, how can we make long voyages). We
have the International Space Station Program, which is truly a world
program. And, in space science, we have an incredibly wide variety
of programs, including the Hubble space telescope. Including the
Chandra X-ray Astronomy Facility. And, all of these things work
together for the success of NASA. But, of course, in any big organization
there are some stars. And, I think Hubble is one of those stars
that shows the best that NASA can be. And, even when other programs
have problems, when we lose a Mars probe, you know, it's a terrible
thing when something like that happens. But then a week later Hubble
makes some big discovery, and I think people then realize that,
you know, you have to take big risks and sometimes you fail. And,
sometimes you take big risks, like Hubble, a very difficult project,
and it excels for years and years. And, I think we should really
cherish those, learn from the mistakes, and make other programs
better.
How
does, in your opinion, STS-109 compare, as far as complexity to
the other servicing missions?
I can really
only best compare STS-103, the 3A servicing mission, to this current
one. Although I'm certainly a student of the other missions, of
STS-82, which ended up having five EVAs, and STS-61, which had five
EVAs. As we service Hubble through each of these missions, the first
servicing mission, second, and then 3A, each time we get a little
more ambitious. I think we saw that on the last mission that we
had three EVAs that turned out to be 8 hours each. We like to do
space walks that are around 6½ hours; that's the best for
the suit and also for the people inside. That's a lot of time to
be outside working. Eight hours was a long time. I felt comfortable
with that. I think Steve did. But I would say at the end, we were
getting pretty darn tired. And I'm sure Mike Foale and Claude Nicollier
would agree as well. So, on this mission we've put a lot of extra
effort into trying to keep the EVAs, the space walks, at 6½
hours - with the exception of the third EVA that will probably go
more like seven. That's if everything goes well.
Right.
If things don't
go well, of course, you know, you never know. It might stretch a
little bit longer. But, in the process, we haven't really cut any
content. We're still doing everything that we were asked to do on
this mission. And, the way we've done that is to make it much more
tightly choreographed, to make sure that both crewmembers, you know,
are going full-bore all the time. And, that's going to be a challenge.
I would say that, in terms of the amount of content we have on this
mission, this is probably the most content-full mission we've ever
done on the space shuttle. As far as the space walking activities.
In fact, pretty much from flight day 2, well, flight day 1 is getting
to orbit (and that's a challenge in itself), pretty much up until
we deploy Hubble and including Hubble day, everybody on the crew
is going to be going at, you know, full throttle the whole time.
Because once we get to orbit, we have to get everything ready to
go as a spaceship. Then, we have rendezvous day, five EVA days (all
of which are as challenging or more challenging than anything we've
ever done in space before), and then a deploy day, which in itself
is another challenge. And then, we get to sit back and breathe a
little bit--
Okay.
-- for a day
before coming home. So, probably the hardest things we're doing
on the PCU day and just the sheer number of things that we have
to do make this one of the most challenging missions.
And,
you wanted to talk about the ungrapple and deploy day. Now, can
you take us through what's going to--
Sure.
--
happen there.
One of the
days that'll be the most exciting will be actually deploy day. And,
that's because we've finished all the hard work out doing the EVAs,
and now we have the hard work of getting Hubble ready to go, making
sure that the aperture door opens, that the high-gain antennas are
deployed, the solar arrays are ready to go, and then finally opening
up the latches. Nancy will take the telescope up, put it over the
payload bay, and then very gently open up the arm snares and back
away. At which point Scott Altman will fire the shuttle's jets to
back out from under Hubble. And, the reason it's so interesting
is that the particular approach that the shuttle does under the
orbiter takes the Hubble right over our heads. It goes right over
those overhead windows. You know, they're big windows. And it's
a 24,500-pound telescope, plus we're adding some things this time.
And, it's big. And, so the effect of this telescope going right
over your heads…on STS-103, when it happened, even though we
expected it, sort of instinctively everybody ducked as the telescope
went over. And once it's gone, our job is basically done. You know,
we have to do some maneuvering to make sure that we back away from
Hubble. But then, we get to watch this great observatory that we've
now made much better recede off into the distance. And, I'm expecting
I'll have some mixed feelings at that point as I did last time that,
you know, here's my friend the Hubble telescope and we're leaving
it again. But it's just a beautiful sight to see the limb of planet
Earth and this jewel in the sky going back out to do astronomy.
Okay,
John, something happened with Hubble late last year to kind of change the complexity and the focus, a little bit, of the mission. Can
you explain what happened and why it affected it like it did?
Last summer,
the summer of 2001, one of the reaction wheels on the Hubble space
telescope, what we call a reaction wheel assembly, burped a little
bit. And, a reaction wheel is the device that allows Hubble to point.
And, it's…like a bicycle wheel in a container that spins a
couple of hundred revolutions per minute. And when they want to
change the orientation of the telescope to point from one star to
the next, they'll add some electrical current to a motor that causes
it to spin faster. And, due to Newton's Laws, that will cause the
telescope to slowly rotate. They have four of these, at different
angles, that allow them to point anyplace in the sky. In order to
know how fast the wheel is spinning, they have a tachometer, just
like in your car; it tells you how fast the engine is turning. In
this case, it tells them - the space telescope science control team
- how fast the wheel is turning; the operations team. The output
from that failed. It's just like if you're driving along in the
road, and all of a sudden your tachometer that tells you how fast
the engine's turning goes to zero. Well, you know your car's still
moving down the road. You know the engine is still turning. But,
you don't know how fast. And, that's what happened to the Hubble.
And so, after all of the scrambling and figuring out that the wheel
was still running, the guys at the operations center said, "Well,
we can still do science." And, late last year, the investigation
board that tried to figure out, "Okay, now what part in the
electronics actually failed?" when they finally figured out
from the analysis what had failed, they decided that the best thing
to do for Hubble and for Hubble science was to put in a new reaction
wheel assembly. That that would provide the most protection for
everybody to do science with Hubble.
So,
it is working. But, you're still going to replace it just as a preventative
thing?
Well, the reaction
wheel is still working. But, because we don't know how fast it's
spinning, if we have a subsequent failure of another reaction wheel
or of that reaction wheel, it could put Hubble in a position where
it might not be able to do science. And, that's what we want to
avoid. So, on this mission we're going to change out that reaction
wheel. And, that's what we decided late last year.
Can
you talk a little bit about how that's changed the crew's focus
on the mission?
Since we've
added the reaction wheel task somewhat late in the game, we have
to first of all learn how to do it. And so, when it was finally
decided that we were going to swap this one out with a new one,
we went back into the Neutral Buoyancy Laboratory (the 6-million-gallon
pool of water) in our space suits and spent a couple of days figuring
out exactly what the best way to do the task is, and then training
it. One of the neat things about doing the reaction wheel late in
the game is: we were very mature in our training. We would go from
run to run, and our times would be steady, our skills are high.
So, we kind of are at the point that we've peaked in our training,
ready for the mission; and now we're just in a maintenance mode,
to stay at that high level for the real event (which will happen
later next month). Adding the reaction wheel is kind of like adding
a little bit of spice to a meal. It's something that…has allowed
us to expand our skills a little bit and learn a new task. And,
that's something that's fun. Astronauts love to do that! So, we
went in the pool, we learned how to do this task, and it turns out
it's about an hour long. So, this is, in the scheme of things, we're
going to do five, 6-plus-hour EVAs, 30 hours. We've added one hour
more of work. And, we've looked at where the best place to put it.
And so, this is going to be replaced at the end of EVA-2.
Okay.
So, Jim and
Mike are going to do this task. Mike will actually be replacing
it on Hubble. Jim will help him in the carrier to swap the old for
the new because Mike's on the arm at that time. And, they'll do
that after the solar array's all complete. One of the reasons to
put it on day 2 is, it's the best match in terms of time. But, also
we have alternatives. Let's say that day 2 goes long. We can always
move it from day 2 to day 4, as it turns out, which will also be
Jim and Mike. And, if we don't get it on day 4, we can finally get
it on day 5. So, we have three opportunities to do it. And, we're
all cross-trained to be able to do this task.
Is
there a certain bit of comfort in knowing that this task is one
that has been done before in Hubble, unlike some of the things you
guys are going to be doing?
On STS-82,
they changed out a reaction wheel assembly. And, almost certainly
by coincidence, it's the same one that we're going to change out.
This was a random failure of a part on an electronics board. Hubble
suffers remarkably few failures, given the harsh environment that
it lives in. And, so it's really coincidence that it's the same
reaction wheel! But we have talked to Steve Smith and Mark Lee,
who replaced it on STS-82, the second servicing mission. And, by
talking to them, you know, we picked up all the little tips that
they've been able to give us on some of the subtleties of what orientation
to put it in, how easy the connectors were. And, that has given
us a lot more confidence that this is a well-defined task. I kind
of think of this task almost as an elegant task, because it is so
closed. It's well-defined. It's kind of a round object. It's about
2½ feet wide. It weighs 105 pounds. And it just looks nice!
And so, the whole task of taking it out, swapping it, and putting
it back in flows very smoothly. So, it's in fact a very nice task;
and something, I think, Jim and Mike will have fun with.
Can
you talk, take us through, how that EVA, how that part of the EVA
is going to go? What Jim and Mike are going to do?
Well, we'll
start out in one of the equipment bays with all the electronics,
about halfway up Hubble. And, Mike will open the bay six door; and
it's just held on with the same kind of bolts that are ubiquitous
on the telescope. And, then he'll disconnect four connectors, move
them out of the way a little bit. And, the reaction wheel has a
nice handle on it. Mike will tether to it, and then there's three
bolts that he'll remove. And then, with Nancy's help driving the
robotic arm, Nancy will, with Mike, just take it straight out of
the telescope. In the meantime, Jim will be all the way in the back
of the orbiter, behind what we call the MULE (the multi-use carrier);
and he will have opened up a box called the large ORU protective
enclosure (it's just a big metal box) that contains the replacement
unit. Once Mike gets close, Jim will take it out of the box, float
up to the side of the orbiter, they'll do a handoff (one for the
other), Mike will take it back up, reinstall it, and close the door.
It
sounds like you guys are approaching this with some enthusiasm actually.
But, are there some, just some concerns about, just the change that
this has caused in the mission?
I think the
changes…we are looking at this with some enthusiasm. I think
it's a very pretty task, as I've said, and something that I think
Jim and Mike will enjoy. On the other hand, it's still at a cost.
It's still adding time to our EVAs. The first EVA we're expecting
to go about 6½ hours. Now, with the addition of this task,
the second EVA will probably go a little bit longer. And so, the
only concern I have is that as we're out there working and the time's
going on, that Jim and Mike might be getting a little bit more tired.
To balance that, this is a very straightforward task; and so I think
it is one that they'll be able to do with, you know, with elegance.
The task that they were going to do, we've had to move around to
other days. And so, some of the other days may get a little bit
longer as well. Specifically the fifth day, we might have to install
what were called aft shroud latch repairs. We have some broken latches
on the big doors. And, Rick and I will probably have to install
at least two of those. And so, that's going to add about 15 minutes
to what might have been an already long day. But, I think that's,
you know, that's just what we have to do to keep Hubble happy.
I
guess lastly, without, or maybe elaborating on the obvious, what
particularly will replacing this unit do for Hubble? What's the
benefit?
The biggest
benefit that we'll get from replacing the reaction wheel assembly
on this mission versus delaying it to a later mission is that we're
buying insurance. And, I don't want to call it "cheap insurance"
because nothing that we're doing is cheap. We're doing it for a
very serious reason. But, we're buying insurance that Hubble can
stay healthy and continue to do science until such a time that we
have another servicing mission, whether it's two, three, or four
years off, and that it will do productive science in the time between
missions. And, that's really the crucial thing. We're putting the
advanced camera for surveys in on this mission; and we want to make
sure that, you know, all the fantastic discoveries that it's going
to make are possible. And to do that, all the other systems on Hubble
have to work well, including the reaction wheels.
Just
one more. How different or similar is this from when you were training
for STS-103 and the gyros went and you guys had to change gears?
How…just in complexity and whatnot?
When we started
training for the original third servicing mission, we had a lot
of the elements that are now on this 3B mission. And, about six
months out from our proposed launch date, we had a gyro failure.
And, these are very small gyros that help the telescope determine
where it's pointing, whereas the reaction wheels are large ones
that actually do the pointing. At six months out, our mission changed
totally. We went from six EVAs to four EVAs; and the emphasis was
on getting the gyros in rather than putting the new scientific instruments
in. Six months is a long time, and long enough that we were able
to really change our training plan, learn the new tasks, and get
set in our ways. Whereas with the reaction wheel assembly, you know,
we were basically ready to go with a mature plan; and so we've had
to shuffle things and add this in very late in the game. So, it
adds a little more of the, you know, the excitement to the mission.
You know, something that's unexpected. And, not a bad surprise;
but a surprise nonetheless.
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