-Last name. -Diaz.
-Okay, thank you. -Go, Don.
-Good afternoon.
Welcome to NASA Headquarters
and today's STS-103 preflight briefings.
The continuation today, we will be talking
about the Hubble payload
as with our panel of experts here,
and we'll lead off with Dr. Ed Weiler,
who is the associate administrator
for NASA's office of Space Science,
followed by Dr. John Campbell,
who is the program manager for the Hubble Space Telescope
at Goddard Space Flight Center.
Next to him is Debra Henretty,
who is an engineer at the Engineering
and Navigation and Guidance Center
at Goddard Space Flight Center,
and rounding out the panel is Dr. Anne Kinney, the ...
Pardon me ... the director for NASA's Origins program
at NASA Headquarters.
Ed.
-Good morning, Don. Three space shuttle flights
and the talents of about 16 astronauts
and the combined talents of thousands of engineers
and scientists have combined over the past 10 years
to make HST, the Hubble Space Telescope,
the most successful science mission in history.
Hubble is the best example ever of the successful marriage
of the human space program and space science.
Astronauts have deployed,
repaired and maintained the Hubble and enabled it
to peer to the farthest reaches of the early universe,
to prove the existence of supermassive black holes,
to observe young solar systems in the process of formation
and much, much more.
But perhaps most importantly,
Hubble has brought science to the American people
on a regular basis through the mass media and the Internet.
To ensure that this large taxpayer investment
continues to pay excellent science
dividends well into the next decade,
if not the millennium, NASA will launch a third Hubble
servicing mission in a few weeks.
It will be a mission of both repair and improvement.
Astronauts will install six new gyros
and perform a brain transplant
by replacing a 1960s computer with a 1990s model.
Hubble will also get new skin in places, insulation
and an improved battery charging system.
I did a calculation last night,
and we're well beyond a billion miles yet,
but we are still on our original quart of oil and oil filter,
so we want to change those, just kidding,
but I think about my own car,
which has over 100,000 miles on it.
I think the reason I keep it is I figure
if Hubble can go a billion,
maybe my car can go a few more miles.
To give you specific details on this mission,
I'll turn it over to Dr. John Campbell,
who is our program manager at the Goddard Space Flight Center.
-Thank you, Ed. Good morning, everyone.
This mission, as Ed said, is to repair and improve Hubble.
Hubble continues to produce this spectacular science,
and our job is to keep Hubble going by repairing it.
Our job is also, whenever possible,
to produce improvements that can open up
new areas of scientific investigation.
Now, to give you some context of servicing mission 3A,
it is 1/3 of the missions
with a planned total five missions for Hubble.
Hubble was launched in 1990.
There was a servicing mission in 1993,
one in 1997, the one coming up in December.
There will be another one about a year and a half later
in the summer of 2001 and 2 years after that,
the last servicing mission in 2003,
and then we'll extend Hubble's life until about 2010,
and that will be the end of the mission.
Now, for this mission, I'm going to show you a bird's-eye view
with Hubble docked to the shuttle.
The docking device there is called a flight support system.
It's a lazy Susan thing that latches on
to the aft end of Hubble.
It allows Hubble to be rotated and tilted,
and this allows the astronauts for easy access
into any of the compartment bays that Hubble has to have open.
The lazy Susan device also has an umbilical
so that Hubble can be powered by the shuttle,
and you will have seen that
in front of that flight support system
is another carrier, forward in the bay,
and it's called ORU carrier, orbital replacement unit.
That's just jargon for black boxes, ORUs,
and that carrier has several containers
that those black boxes are placed in.
It gives a soft ride.
There's foam in some of those carriers,
and also it's thermostatically heated
so that the boxes coming up are kept warm
and kept safe during the launch process.
Now, the most important thing that we're doing on this mission
is to change the gyros,
and these gyros that are in Hubble
are the most accurate that have ever been produced,
and they are required to get the kind of science
that we get from Hubble.
One example is that Hubble has looked at the same target
in the sky for up to 10 days, a very, very long time exposure,
and without those gyros,
the stars would just be fuzzy points of light.
The gyros are what help to keep Hubble stable and day after day
recording points of light and sharp images of galaxies.
Now, to give you more information about those gyros,
Debbie, my colleague here,
will tell you some more about them.
-Okay, thank you, John, as Dr. Campbell stated,
one of the main focuses of the servicing mission
is to replace the gyros on Hubble.
The controller uses gyros for maneuvers
and high-accuracy pointing.
This high-accuracy pointing is necessary for science.
The controller uses a minimum of three gyros for this pointing.
So far, out of the six gyros on Hubble, we have lost three.
If we lose another gyro, we will go into a zero-gyro safe mode.
While this does not pose a threat to Hubble itself,
it does mean loss of science until the gyros can be replaced.
I would like to note, however, that while we are operating off
only three gyros, the science program
is proceeding perfectly well at this point.
The next thing I'd like to do
is take you on a journey inside of Hubble
so that you can see where the gyros are located.
The gyros are on the back end of Hubble.
There are six gyros in three boxes with two gyros per box,
and you're going to see one of those boxes coming up.
The gyros are cylindrically shaped,
and you'll see a single gyro coming up,
and the blue that you're about to see
is fluid that's inside of the gyro,
and now we're going to zoom in on a flexible wire.
It's shown broken here because we believe
that this is the cause of the failures in the gyros.
Now, I have a real gyro here, and I want to show you.
You're really not going to be able to see this,
but inside of here, there are those wires.
They're about the thickness of a strand of hair,
and you can't see them, but they are inside of here.
After the gyros are assembled, and the cap is back on,
this gyro is filled with fluid.
This fluid has a corrosive effect on the wire inside
and can cause it to break.
The wire is composed of a silver copper alloy
that is 85 percent silver.
The fluid corrodes the copper and leaves only silver.
Once the wire is in this state, it is considered to be brittle,
and it can break.
To give you an illustration of what this means,
we use a bigger example, a larger-scale example,
of a stone wall.
The silver is like stone, and the copper is like mortar.
In a stone wall, if the mortar is washed away,
the stone wall may remain standing, or it may not.
In a similar fashion, this wire, once the copper is corroded,
the wire may break, or it may not.
There's a great deal of uncertainty.
These wires have lasted in this state for many years,
or they have broken, as seen on Hubble.
To prevent this from happening, a new and improved manufacturing
process has been developed to try to prevent the fluid
from interacting with the wire and corroding the copper.
This new process has been used on five of the six gyros
that are replacement units for this mission,
and you may ask why only five and not all six,
and the answer is simply because we ran out of time.
There was not enough time to assemble the sixth gyro.
There will be no gyros replaced on servicing mission 3B
unless, of course, we have failures,
but then again, on servicing mission four,
we will replace all six gyros.
All six will have the new and improved manufacturing process.
They will all be replaced in an effort
to ensure that we will maintain science until 2010.
Now, I'd like to conclude by showing you
footage of the astronauts
in the clean room at Goddard handling the gyro boxes.
There's the three boxes, and here is an astronaut
lifting out one of the boxes out of the Hubble mock-up,
and he will replace that with a replacement box.
That concludes my discussion on the gyros,
and now John is going to continue with the remainder
of the servicing mission.
John. -Thank you, Debbie.
An improvement that we're doing
is to replace the old-style computer with a modern computer.
This computer is stored in one of 10 equipment bays
that circle the spacecraft, and a graphic coming up now
is showing how the astronauts have the door open
in one of these equipment bays to install the computer.
The computer is shown in the picture there,
and it's just truly just a black box.
The computer is based on a 486 Intel unit,
and there are three different separate computers in that box,
each one independent,
and at any given time, we only use one,
so there are two different strings,
then, or two different computers
that are redundant in case we should need them.
This computer gives us greatly increased on-orbit capability.
During the first servicing mission,
we installed what we called a coprocessor,
which was Intel 386-based, and that did some improvement,
and now, when we install this computer,
we will have increased the central computer memory
by a factor of 31 times
and processing power by 40 times.
What that does for us is it allows us a little ...
It allows us to move some function in one orbit
to reduce operating cost and allow us, as Hubble agents,
to do operational workarounds if need be on the computer,
and maintenance costs are greatly decreased
because the computer is now programmed
in a modern programming language,
which makes it easier to program and faster to program.
To be able to keep Hubble steady along with the gyros
are fine guidance sensors.
There are three fine guidance sensors on board.
The way we target a star or a galaxy,
we place the star or galaxy
in the aperture of one of the science instruments,
but before we do that and when we do the science planning,
we have to find two stars that are nearby that galaxy
or that star that we want to look at,
and those two stars are then
placed in two different guidance sensors,
and the guidance sensors lock on to those stars
and then with the gyros keeping everything stable,
and we're able to home in on that target and stay there.
In servicing mission one, we removed a fine guidance
sensor, replaced it with a spare,
and you saw the picture of astronauts in servicing ...
Sorry, I said servicing mission one.
I meant servicing mission two, and you can see the picture here
with the astronaut handling the fine guidance sensor.
It's about 5 1/2 feet long, weighs around 500 pounds,
so we had a spare on the ground, placed that in Hubble,
and the one that was brought back
after servicing mission two, we've refurbished.
We will install that in this upcoming servicing mission.
The one that we take out will refurbish
and finally install that in servicing mission four,
so as we get into the later years of Hubble,
we'll have three fine guidance sensors
that have been refurbished,
and they should last for the life of the mission.
Now, when Hubble collects science data,
it stores it on board, next graphic, please,
and eventually transmits through a radio transmitter
the science data to a geosynchronous satellite,
one of NASA's tracking data and relay satellites,
and then the science data is beamed down to the ground,
ends up at Goddard Space Flight Center
and then finally up to the Space Telescope Science Institute
in Baltimore, where the science data is processed.
One of the two radio transmitters has failed,
and we plan to replace that.
In the meantime, the one good radio transmitter is doing
the job perfectly well
in terms of being able to transmit science data,
and there hasn't been any impact on the science.
Now, our most important product is really science data
and science data production,
and since the early years of Hubble,
we've been steadily improving Hubble
and gaining more and more science data to today.
We're actually producing 11 times more than
when we started out.
The science data has to be staged on board
before it can find a transmission time
to go down to the ground, and it is stored on recorders.
When Hubble was first launched,
there were three mechanical tape recorders on board,
and these mechanical recorders are much like
the reel-to-reel tape recorders that some of us still remember,
and they don't store a lot data.
They're unreliable.
You have to rewind them after you put data on them
before you can dump them,
and they don't do the job anymore.
In servicing mission two,
we installed a solid-state recorder
that's just composed of computer chips,
a factor 10 greater than storage capacity
of the mechanical recorders, and that's working very well,
and it's handling the science data that we're getting down,
and we're putting up its twin
to replace one of the other two mechanical recorders,
so we have it to help us store science data
and improve production.
Now, Hubble is in low earth orbit,
and around every 97 minutes,
it goes through first a day cycle
and then a night cycle.
During the day, Hubble is powered by solar cells
that are on solar rays, and during the night,
Hubble is powered by six batteries.
Now, these batteries, of course, have to be recharged,
as they come back out into the sun,
and the batteries are almost 10 years old now.
They've aged.
They still do the job,
but they've become more sensitive
to the way they are charged,
and they're susceptible to overheating,
and what we're planning to do is put a battery voltage
charging improvement kit on each of these batteries,
looks like this.
The astronauts will go up,
disconnect the connector from each of the six batteries
and then put this in line.
There's a wing tab connector. You can see this.
That is for ease of astronaut gloves to handle that,
and then in this box is just simple circuitry
that helps the charging cycle not be so hard
and keeps the batteries at a cooler temperature.
As Hubble goes through its day night cycle,
it, of course, is full in the sun,
and the skin of Hubble can reach around 180 degrees
Fahrenheit.
As it goes into night, that same skin can reach
a temperature of minus 130 degrees
Fahrenheit, an excursion of almost 300 degrees.
Now, boxes, instruments, computers, of course, don't work
well when they go through those kinds of excursions,
and so the thermal skin that's on
Hubble, composed of multilayer insulation,
is there to keep the temperature inside Hubble constant.
In fact, it's kept at nearly room temperature
with very small excursions, and once boxes are put in
Hubble, they're in a very comfortable environment.
Now, over the years that sun radiation, ultraviolet
and also the local radiation environment
has degraded the skins.
I heard a question earlier that said, did we expect this?
And the answer was no,
that Hubble is really leading the pack here
in terms of spacecraft that have been in orbit,
and samples have been brought back
so that we can understand what's going on.
Outside of the Russian Space Station, it's really only ...
Hubble is really the oldest spacecraft
from which we've brought materials back
and understood what's going on
and what happens over a long period of time,
so the insulation has cracked and peeled,
and we're going to install corrective action on that.
There's two particular things we're doing.
On the equipment bays, on the doors,
the insulation has degraded,
and we're placing stainless steel sheets on those doors,
and now I want to roll a little animation
that will help you better understand
what we're doing with the remainder.
This is a cartoon of a stainless steel sheet
going on one of the payload bay doors, equipment bay doors,
and now you see several rolls of insulation
unrolling to cover the light shield and the forward shell.
There's four vertical rolls, three horizontal rolls.
The largest one is 18 feet long and 5 feet wide.
Now, following immediately is a little video clip
that shows the astronauts in street clothes
around a mock-up at Goddard Space Flight Center
that's a full-size mock-up
where they're training to do this insulation repair.
There's a roll, and here is Claude Nicollier
unrolling one of the horizontal rolls.
Notice the words and lettering all over that insulation.
Those are installation instructions,
so that says where things go, how to align things.
There's arrows all over the place
to keep those rolls, wallpaper-like rolls, aligned,
so one of the things that we kind of get a kick out of
is that a creative engineer came up with the idea
of how to install a stainless steel plate.
It turns out that there's four holes in the corner
of each one of those equipment bay doors,
which were used to let the air vent out at launch,
and our engineers came up with a simple bottle stopper idea
to just plug that into the hole of the vent door,
and then that holds the stainless sheet there
on that door, and then here is a life-size.
You can just see it just clicks down and locks right on,
so that's kind of neat, so that completes the story
now of the various things that we're planning to do.
As I said, we're repairing some equipment.
We're improving some equipment,
and we hope to continue to do great science
until the next servicing mission
rolls around another year and a half,
and now Anne will talk to you some more about this science.
-Thanks, John, so at this stage, we're about 10 years
into the life of Hubble Space Telescope,
and everything that you've heard about today is to help ensure
that we'll have an additional 10 years to be able to continue
to do these wonderful science observations.
What I'd like to talk about today
is my personal list of observations
where Hubble Space Telescope observations
have changed the way that we think about the world,
not just a nice science result but actually had an effect
on the way that we think about the world,
and then in the end, I'd like to show you a new science result
that comes from Jeff Hester,
a really beautiful image of a nebula,
so number one on my list
would be the comet collision with Jupiter.
Now, this was an example where we ...
I didn't actually want the video yet.
The comet collision is an example where a comet
is approaching the Earth,
and we see the comet break up, and we can predict
that it's going to run into the body of Jupiter,
and then it smacks into the body of Jupiter,
and we actually see something that we consider a cosmic event
happening in our lifetimes
and in front of our eyes with Hubble Space Telescope.
The size of the debris left afterwards
is the size of the body of Earth.
The small part of the debris is the size of the body of Earth,
so that is sort of an object lesson that is pretty profound.
We live in a universe where things happen,
and they can actually happen on a pretty short timescale.
There was about 2 years' notice with that particular comet,
and that was a spectacular Hubble Space Telescope result.
Another example, I think, of the way
Hubble Space Telescope images have changed the way
we think about things is with the Supernova 1987A.
Now, this went off, obviously, in 1987,
and then Hubble was launched in 1990
and started looking at it and very quickly observed
something we'd never seen before:
triple rings illuminated by this explosion.
Now, this is a massive explosion that's going off.
In the past, all we've ever been able to watch is the decay time
as these things get fainter and fainter,
but now we can actually see the anatomy of a supernova
explosion, and what we're waiting for now
is for that really powerful blast wave
to hit into those rings, and we will have a blow-by-blow
of how a supernova explosion proceeds in the universe,
and this is really something very important to us
because this type of explosion
is what disperses oxygen in the galaxy,
and I don't think I have to go into why oxygen
is important to us, so that's another example
where I think Hubble Space Telescope images
really impact the way that we look at the world.
Another one of my personal favorites
is that Hubble Space Telescope identified the sources
that host the gamma-ray bursts.
Gamma-ray bursts have been an enigma
for about 20-odd years,
and astronomers didn't even know if they were local or cosmic.
They didn't know if they were within, you know,
multiple light-years
or if they were outside the galaxy,
and Hubble Space Telescope identified them
as being hosted in distant galaxies,
and that was a result that we'll hear more about
as the years go on and that I think is going to be
a very, very interesting story to follow.
Another of my personal favorites is that Hubble Space Telescope
provided definitive proof for black holes in galaxies,
and not only in quasars and active galaxies,
but also in normal galaxies and even small galaxies.
In fact, Hubble discovered so many black holes
that Art Buchwald had a column one day where he listed articles
that he never wanted to read in the newspaper again,
and one of them was "Hubble Space Telescope
discovers another black hole,"
but that has really affected our vision of galaxies
that it appears that most galaxies
are actually the hosts of black holes in their very center,
and then finally, I think probably the topic
that you'd have to say Hubble Space Telescope
has had the most impact on is galaxy formation
and a view of the very deep universe,
and this, of course, was a spearheaded
by the Hubble Deep Field,
which was Bob Williams' discretionary proposal
that was really quite unprecedented
in the world of astronomy.
Ten days were spent observing this field
with the help of a team of astronomers working on it.
The data was reduced as quickly as possible.
It was released, I think, within a month to the world,
and it's probably the single field
that has had the most scientific results on one field,
and it's impacted everything about the way
we think about galaxy formation, and it actually also changed
some of the sociology of astronomy
because people started exchanging results on the Web,
and it really fomented a lot of activity
in that field that's been ...
that really has paid off beautifully.
And now if you could roll the film of the greatest hits.
Here you see Jupiter,
and the smallest central debris is the size of the Earth.
This is the Orion Nebula, host to formation of stars.
This is a globular cluster, planetary nebula,
end of a star's life.
This is one of those beautiful galaxies, M87 active galaxy,
and proof for a black hole, a velocity dispersion.
Here is a colliding galaxy, Sen-A,
and finally from the Hubble Deep Field,
just a snippet from the Hubble Deep Field.
So of course if we were to show you all the greatest hits,
you'd have to sit here for another hour or so.
But now let me show you a new result
that comes from Jeff Hester,
and let me just talk about it a little bit first.
This is a nebula that, let's see, we've been discussing
all morning how to pronounce it: Trifid, the Trifid Nebula.
Let's try that?
The Trifid Nebula, okay, so this is a region of star formation
that you could call it a birthing region for stars.
Stars really tend to like to be born together in gaseous clouds,
but then what happens
is that the most massive stars form first,
and they turn on, and they're powerful, bright stars,
and they start to blast holes out of the nebula,
and when we show the video, you'll see what I mean by that.
There's actually bright paths
where the thing has started to blast out,
and this is another area where I think Hubble has really
had a nice impact on the way we think about star formation
because what happens is that the massive stars
start to impact the way the less massive stars form,
in that they blast away at the nebula,
and I think the way Jeff Hester put it was
that it's like a blowtorch on a block of ice
when that hot star turns on.
So let's take a look at that video.
This starts with a ground-based image
from the 1.5-meter at Palomar, and here you see a nebula.
You see those spots that have been blown out.
We zoom in on the area of observation,
and you can see that bright red shows
you the direction of the brightest stars
is about 8 light-years from the really bright star,
and here you can see several different features,
a kind of a spiral jet from a very young star
and then a pillar where the light has been blasted away
by the central star.
So this is just an example of very recent,
very excellent science going on with Hubble Space Telescope.
And we all very much look forward to be telling you about,
you know, 10 more years of great science
from Hubble Space Telescope.
Don? -Thank you, Anne and panelists.
Okay, we'll start taking questions
from reporters here at headquarters,
then go to Johnson Space Center and Kennedy Space Center.
Please wait for the mic and give us your name
and affiliation, Paul.
-Yeah, Paul Hoversten, USA Today.
A couple questions: For Debra,
what's the fluid in the gyros, please?
-The fluid is bromotrifluoroethylene, BTFE.
-You'll get the...
-Okay. All right.
Okay, thank you, and for Dr. Campbell,
if the original computers are like the Intel 486,
would you say what you're putting in
is sort of like a Pentium III?
Can you think of an analogy we can use for that?
-Well, it's like between a factor of 30 and 40 times.
I guess that's probably right.
I would have guessed the Pentium was a factor of 10
maybe than a 46, but something like that, yeah.
-Okay, and finally for Ed, can you talk a little bit about
how critical this mission is to the science of Hubble
and whether or not you're hearing from astronomers
all around the world and they're very expectant,
and, I mean, can you just sort of elaborate on the importance
of a successful mission here to the telescope?
-Well, as you know, Paul, you know,
Hubble was designed with servicing in mind.
I mean, it was not designed to last 15 or 20 years
without any astronaut servicing, so parts are failing.
We've lost a, you know, wideband transmitter without a ...
You know, we have ... Of course, we anticipated
losing one at some point in time,
so we had two of them, and we're using the backup now.
Slightly important because without a transmitter,
you have no data.
This mission is really to protect ...
We're really not making any scientific
improvements in this mission.
That's going to be the one in about a year and a half
when we put on an advanced camera,
when we hopefully revive the NICMOS, etc.
This mission is really to protect the science,
to protect that investment.
You know, we have a large amount of money invested in this.
We've gotten very used to our nice big fat checks
every month from our mutual funds, etc.,
and the sciences are those dividend checks.
We're down to three gyros, but we're lucky.
Back in February, if you asked me
if we could have made it to December,
I would have probably not taken that bet.
I would have probably bet that we'd have had a gyro failure,
and if we had one more gyro failure
between February and now,
we would have lost all science on Hubble
until we went up there with a shuttle to fix it.
So we've been kind of lucky for a change on Hubble.
It's kind of a nice experience for a change.
How long that luck would last is anybody's guess.
I mean, the remaining three gyros could go 5 years.
They could go 10 years, or they could fail tomorrow.
One could fail tomorrow.
I think IUE, the International Ultraviolet Explorer
went 18 years.
One of the gyros lasted 18 years.
-Two of them. -Two of them.
We won't speak to the other two.
That's failed.
So it's ... The analogy is very good.
You know, you've got that brick and mortar wall.
When the mortar starts peeling away,
that wall could fall right on top of you,
or it could last like, you know, the ones in Stonehenge had last.
So this is making sure we keep the dividends flowing.
That's really the way to describe this mission.
As I said, we spent billions on this program,
and this mission will continue the dividends,
scientific dividends flowing.
So the gyros are the most critical element.
The batteries are becoming a worry.
They're not really a major concern, but they're a worry,
so we're going to take care of that heating problem also.
And the insulation again is a long-term thing.
You know, is it going to cause the mission
to fail tomorrow or the day after?
Of course not, but by taking care of it now,
hopefully we won't have to worry about it again
for a long time to come.
So we're doing some short-term ...
I want to go ...
This is not a routine servicing mission.
It's not an emergency mission.
It's somewhere in between, so we're taking care
of some long-term concerns,
taking care of some short-term concerns,
and we're really leaving the upgrading of science
to the mission in about 18 months.
-Okay.
We've got a question in the back,
and then Kathy Sawyer in front.
State your name and affiliation.
-The gyros used in aviation don't have any fluid in it,
so can you explain why you need fluid in those gyros?
And second question is, what's going to happen
after 2010 to Hubble Telescope?
-Take it first. -Okay, the gyros
have fluid in them because they're floating gyros.
The fluid is necessary as a part of the ...
for the mechanism inside to rotate.
It's ... I don't think I could make it too simple.
It would be pretty technical, but very simply just to say
that the fluid is necessary for the mechanism of the gyro
spinning for that to work.
-On the "What do we do with Hubble after 20 years?"
there are two options.
One we're really not too seriously considering.
One option would be to somehow attach a rocket to it
and then blast it up to a very high orbit
so that it would be safe for eons.
I don't think we've really figured
out an easy way to do that.
The most likely option that in 2010,
which corresponds to the next maximum of the solar cycle,
at maximum of the solar cycle,
the atmosphere of the Earth spreads out,
expands, will slow down Hubble,
and without any shuttle interaction,
the Hubble would wind up coming down,
and that might not be a good day for where it lands.
So we intend to ... Right now the current plan
would be to bring it back to Earth in 2010.
We haven't made arrangements with anybody,
but I'm sure the Smithsonian would be interested
in an exhibit that would stand 40 feet tall
and may make a very interesting exhibit for kids to see.
Kathy?
-Kathy Sawyer, The Washington Post,
for Dr. Weiler.
You've had some slip in the schedule of this mission,
and I was wondering, have any science missions
that were time-critical been unsettled or ruined or delayed?
Has there been much scheduling problem
with any of the users of this telescope?
-Specific to Hubble or other space science missions, Kathy?
-Well, I had in mind specific to Hubble,
people who had scheduled observations for the time
during which the mission was supposed to occur in October,
and then during the time when it is now occurring in December.
Both of those ... -I got you.
-... time periods might have been a bit unsettled
by the changes and uncertainties.
-Well, it goes both ways.
Those scientists who were anticipated
not getting their observations done back in October
when we were supposed to fly have now
gotten their observations, so they're the winners.
The ones that had planned to get their observations
in early December are the losers.
To the best of my knowledge,
and somebody from the institute could correct me,
I'm not aware of any time-critical observations
that will be lost.
The way we work with Hubble is that
if you lose your observation, it will be rescheduled.
That's not to say there aren't time-critical observations,
but again, to the best of my knowledge,
no comets are hitting Jupiter
this walk and no supernovae have just gone off.
So the answer is probably no,
no critical things are really lost by this.
I mean, and we're not losing any science in essence
because instead of taking off a week or two back in October
for the servicing mission, we'll be doing that December,
so that time was "already lost" anyway.
-Earl Lane with Newsday.
Just to clarify Paul's question on the computer,
it is a 486 that's being put in as a replacement,
right, not a Pentium, and I guess the question is,
why wouldn't you go for a Pentium class?
-All right.
The new computer is Intel 486-based,
and the main reason why it isn't Pentium
is that a computer for a space application
takes on the order of 4 years
to develop from start to scratch,
and for us, there's two major reasons why that's true.
One is that the design has to fit in the Hubble.
There can be no mistake.
When that computer is plugged into Hubble, it has to work,
and it has to communicate with the rest
of Hubble's data system.
And so this isn't a plug-and-play thing
where you can just plug in a printer
like we're used to on the ground,
so that takes a long time.
We do model ... We do first models
and make sure that works, and then test that,
and then eventually build flight units.
The other thing that's different from us on the ground
is that their radiation environment
is a lot more severe up in space.
An example is that some commercial laptops
are frequently brought up into the ...
on the shuttle flights by the astronauts,
and those laptops come to a halt once or twice,
sometimes three times a day because of radiation hits,
and that's unacceptable, too.
The computer has to operate day in, day out,
so we had to select the processing unit
to be sure that it withstood the radiation.
We have memories in there that are not commercial memories
like on your standard computer but are radiation-hardened.
And then finally, we actually tested this computer,
the one that we planned to install.
We tested it last fall a year ago
on the flight that John Glenn flew on.
We took it up into space.
We ran it for 7 days.
That's really not a life test,
but that was kind of a dummy check
to make sure that we hadn't overlooked anything.
So it takes 4 years to develop,
and Pentium really wasn't in the cards.
-Well, let me add two short things to that.
In fact, we are working with the Pentium people,
and JPL is involved to ...
We're currently working to get the Pentium
up to space qualification standards,
hopefully in less than 4 years,
but that's in progress because you have ...
As John pointed out, you have to start early to radiation-harden
these things and design them for space radiation environment.
Not to downplay the 486, I mean, remember what it's replacing.
It's replacing what we call a DF-224.
That was NASA's and the military's standard computer
back in the '60s.
It's not quite like going from a, you know,
a slide rule to a McIntosh or whatever, IBM.
It's close. -All right.
We'll go to the Johnson Space Center for questions now.
Go ahead, please.
-This is Marcia Dunn of the Associated Press for Ed.
What's the latest cost attached to this mission,
both Hubble program costs and shuttle costs?
-Oh, I'm sorry. I missed the question.
-What are the costs for the mission,
the Hubble and he shuttle costs?
-The Hubble-related cost is $26 million,
roughly $26 million,
and the cost for the extra shuttle mission
is about $110 million for a total of about 136.
-Yes, and I was wondering,
when did the radio transmitter fail and why,
and could you give a little status report
of the three remaining functional gyros?
I know there was some quirks in one of them about a month ago.
-I can't remember exactly when the transmitter failed.
I believe it's been almost 2 years now.
We don't know why it failed.
We did a lot of telemetry analysis.
We think one of the power transmitters,
power transistors on the power side of that transmitter failed.
The telemetry seemed to indicate that.
We won't know until we bring it back to the ground
and take it apart.
The three gyros are doing their job.
They're working.
We're doing all the kinds of science
that we've always been able to do with the gyros,
so they are healthy.
-Todd Halvorson of space.com.
On the radio transmitter, have you guys done any studies
on the meantime between failures or have any predictions on
when the one unit that you do have good up
there might go bad on you?
-Well, we're anxious to get that transmitter back.
We expected the transmitter to last for 15 years,
and so it failed it must be around 8 years of operation.
Until we get it back to see why it failed,
we won't know whether that was just a random part failure
and won't affect the other transmitter,
but in fact, what we're planning to do
is when we bring this one back, we'll refurbish it,
and if necessary, we can replace the original one,
the one that we're using right now, in servicing mission four,
so another advantage of being able to service,
to find out what goes wrong,
fix it and then replace a box for long life.
-And just a quick one on the voltage improvement kits,
I'm wondering if you can tell me
what the upshot is of batteries overheating on the Hubble?
-Okay.
First, let me say that under normal ...
When we normally operate Hubble, it's under computer control,
and the computer controls the charging cycle.
The one thing we're concerned about is that
when Hubble goes into its deepest hardware safe mode,
there's a computer that takes over
from the other programmable computer,
and it controls the spacecraft.
What it does is, it takes, disconnects all the load,
turns off all kinds of boxes
to be sure that the Hubble is power safe,
and that's the extended safe mode.
Now, the batteries are used lightly then,
so when they get charged, they start to warm up.
That's the problem.
Now, if the worst case is,
is that if over a period of a day or two,
if we couldn't restore communications,
then the batteries would slowly warm up,
and then finally,
if that should happen and the batteries got too warm,
then the seals would break and the hydrogen in the battery
would then just be dispersed into space.
-This is Miles O'Brien with CNN, for Ed Weiler, I suppose.
Ed, has Hubble answered all of the big questions
that it set out to answer?
I seem to recall a top-10 list at least,
and as you look forward to the next 10 years,
what are the outstanding questions
you hope to see answered?
-Well, Miles, on the second question,
we could probably spend the next hour.
I don't think we want to do that.
Let's see.
Certainly Hubble has answered most
if not all of the top questions
that we talked about back in the 1970s.
You know, it certainly has given us the Hubble Constant,
the age of the universe to a 10 percent accuracy.
It's proven the existence of supermassive black holes,
but we can go through that list,
but I think what's more important is all the questions
it's enabled us to ask for the first time,
and the questions it's also ...
and the things that we thought we knew that we found out
we didn't know very accurately.
Anne Kinney talked about one of them in terms
of the Hubble Deep Field.
When many of went to graduate school, the models,
the belief was that galaxies,
which are the largest forms of matter in the universe,
tens of thousands of light-years across,
they were formed out of the uniform hydrogen
and helium cloud that was expanding after the Big Bang,
and the thought was that such big structures took a long time
to form after that Big Bang, perhaps a billion,
perhaps 2 billion or perhaps even more years.
So we thought when we launched Hubble,
knowing that we had the capability
to see back at least that far, that we would see galaxies
basically in the act of formation,
in the act of being born, and we were quite surprised
because what we saw was pretty well-formed objects
1 billion years after the Big Bang,
perhaps as little as 800 million years after the Big Bang,
which meant that the epoch of galaxy formation
occurred much earlier than most theoretical models predicted.
This is a problem, and Hubble is not going to solve that problem.
It doesn't have the light-gathering capability.
It doesn't have the aperture to see back even further,
and thus was born one of the prime driving forces
for the next generation space telescope
was the fact that we would like to go back
and not just see the infants and the toddlers.
We'd like to go see the act of birth,
that is, how did this universe get started after the Big Bang?
How did we go from a uniform cloud of hydrogen
and helium into the complex universe that we live in today?
Hubble has given us a lot of answers to that question,
but it's posed some even more serious questions
about that process.
Another thing I think Hubble is going to play a major role in,
along with a lot of other telescopes,
is another thing that Anne mentioned,
is the whole issue of gamma-ray bursts.
These are the most powerful explosions in the universe.
For a few seconds, they're more powerful
than the Big Bang itself.
Just until a few years ago, it wasn't known whether
these things were occurring right next door
to us or billions of light-years away.
Through a combination of high-energy satellites,
ground-based telescopes and Hubble,
we've now shown more or less definitively
that these objects seem to be occurring ...
these explosions seem to be occurring in galaxies.
But what are these explosions?
Are they neutron stars coming together?
Are they black holes eating a whole star all at once,
and we're seeing the burst?
We still have no idea, and I think with the advanced camera
which will be launched in a year
or two with the other instruments
we're planning to put up on Hubble
and in combination with the other great observatories
like Chandra, the X-ray observatory
and the space infrared telescope facility,
I think within the next decade, it's not unfair to say
that we probably will get a pretty good answer
as to what these explosions might be.
And it's not just Hubble.
It's Hubble in combination with all these other programs.
We are really in ...
We're not entering, we are in a renaissance for astronomy.
Over the last 10 years, the leaps we've taken in
answering basic questions and again,
more importantly, sometimes it's more important to know
the things you don't know, if that makes any sense.
And I think Hubble has done a real good job
in just putting us in our place.
That is, we don't know all there is to know about this universe,
even though a lot of astronomers thought they knew most of it.
-A question for Dr. Kinney, I think.
It's obviously a very sensible and valuable instrument
which has provided an awful lot of science,
which you just went through your personal top-10 list.
When the space walks are occurring and the space walkers,
as well-trained as they are, are near that instrument,
is that a nervous time for scientists and astronomers?
-That's terribly nerve-racking.
Probably the most nerve-racking for any of us
was the original refurbishment when COSTAR was put in,
and at that time, I was an instrument scientist
with the Faint Object Spectrograph,
and there were booms that had to be moved out with the mirrors
in place to correct the Faint Object Spectrograph,
and if they didn't move to the correct position,
you would block the apertures instead of correcting them,
and, boy, we didn't get any sleep at all
for that whole period because the space walks were at night,
and of course we were working in the daytime,
so we'd get up in the morning, go to work.
We'd go home, have dinner, rest,
and then we'd go in and watch the space walk.
And honestly, there are some people who couldn't sit down.
You couldn't ... It was sort of ...
Europeans have the same response
when they're watching a world soccer match.
They can't sit down, but it was incredibly nerve-racking,
and some of it is very difficult to watch.
You watch with your heart in your mouth
basically because, you know, it really ...
People live and breathe this stuff.
I mean, it really means a lot to you.
I'm sure John would say the same thing.
-Oh, yeah.
That's true, but also, you have ...
When we're actually doing that, you have to suppress that
because you have to try to keep thinking of what might go wrong
and how you would react to it,
so it's necessary to stay cool as much as possible.
-Bill Harwood, CBS.
Two questions, one for Ed and one for John Campbell,
but, Ed, on the cost, following Marcia's question,
just to review my memory, can you tell me
what the projected cost is through 2010 of Hubble,
what that grand total comes to, and I was wondering what ...
I see you shaking your head, but I was just curious
as to what number to put on it, and I was curious
as to what the yearly operational costs are right now
and what they will be after the final servicing mission.
-Okay, we'll have to do this in real time, Bill,
so I hope you have your slide rule with you
or your Pentium, whatever.
The Hubble development cost was about $1.6 billion.
The annual operating cost roughly
is about 200, counting science,
about $250 million a year through to '05,
so that's 15 times 250.
That's about 4 billion, plus 1.6,
that's about 5 billion, 5 1/2 billion.
And then the last 4 or 5 years, we'll be down to an annual cost
as low as maybe 60 or 70, so that's another 300 million.
So what does that all add up to, about 6 billion?
-Six billion, that's right. -Boy, oh, boy.
See?
We can actually do math in real time at NASA.
So that's about $6 billion
spread over 1980 through two-thousand ...
to 30 years, that's an average cost of $200 million a year
from 1980 to 2010,
and that equates to about 2 cents a week per American
over that period of time.
So that's what they're paying for the Hubble.
-Well, that's pretty good off the top of your head.
-Without a slide, without a Pentium, I might add.
-This is for John Campbell or maybe Debra.
I'm not sure which.
On the gyros, I was hoping you could refresh my memory.
I know it's an age-related failure
and not a runtime-related failure
was my understanding anyway,
and I was curious what the operating times
are on the three that are still cooking,
I mean, age and/or operating time on the three
that are still working.
-Actually, it's runtime and not age.
The two of the gyros that are working right now
are 14 years old,
but they only have 4 to 6 years of runtime on them right now.
-Yeah, well, just a quick follow-up, I ...
The embrittlement that's occurring
because, I guess, of the oxygen in the fluid
affecting the flex wire,
I was assuming they were exposed to that fluid all the time,
whether they were running or not.
So I guess I had it backwards.
I'm just trying to make sure I understand it.
-The wires are exposed to that fluid at all times.
It's also a temperature issue.
When the gyros are not on,
they are stored at a lower temperature
than when they are operating, and it's ...
The turn-on of the gyro is what causes the most strain
on the flexible wire, and also
the increased temperature causes more strain on the wire.
Being stored is ... They have to remain stored
and in this condition and still operate,
so that is not really causing a lot ...
as much stress on the wire.
-Hi, Mark Crowe from the Houston Chronicle.
For Dr. Weiler, could you sort of review
what happened with the NICMOS camera,
when it finally lost its cooling and you couldn't use it anymore,
and include in that your work on the replacement cooling system
and how confident you are now that when it's installed,
I gather on the next mission,
that you'll revive this instrument?
-Okay.
I think I'm going to turn that over to John
because he's much closer to that currently than I am.
-Right, and I'm trying ... Okay.
The ... and Anne, I think I may need some help there.
That if I remember right, the solid nitrogen
ran out in January of 1998. Is that right?
-That's right. -Yeah, okay, so that's ...
So since then, NICMOS has been dormant.
Around that time, in around the February/March time frame,
we began the design of a refrigerator that is based
on a high-speed turbine
that runs around 300,000 to 400,000 RPMs,
and that refrigerator was actually tested
on that same flight
that we ran with John Glenn
on the flight where we tested the computer,
and it ran there for 7 days, and we brought it back,
and it's being refurbished,
and we have confidence that it will work,
but it really is pushing the technology,
and the way we're going to address that,
and we'll be talking about it as we come onto this next mission,
is that if it works then we're going to be really happy,
and we'll restore NICMOS.
If it doesn't, then we hope to get some technology testing done
that can help build other refrigerators
that can be used in space.
-That's an important point because this technology
is really critical for telescopes
like the next-generation space telescope.
That will have infrared instruments,
and it will need ...
Those instruments will need to be cooled.
Since the next-generation space telescope
is planned to be at a Lagrangian point around the Earth,
about 1 million miles away from Earth.
It's not going to be visited by astronauts on the space shuttle,
so the idea of using solid cryogens,
which might have a lifetime of 1 or 2 or 3 years,
just doesn't make a lot of sense.
So whether the mechanical cooler for Hubble for the NICMOS works
or doesn't work, we will at least make a lot of progress
toward realizing that technology in the future.
-My colleague corrected me on when the cryogen ran out.
It really was January 1999,
and it was such a blur that between that time
and the host flight in October there was actually ...
developed this model and tested it, flown it.
So it was really a rapid development.
Thanks.
-Okay, we'll take one more question
or two more questions that is from Johnson Space Center.
Then we'll go to the Kennedy Space Center.
So go ahead please.
-Todd Halvorson, Space.com again,
I was wondering, Ed or Dr. Campbell,
if you could refresh my memory on whether the advanced camera
for surveys is the last scientific instrument
that will be going aboard Hubble
or if you could just kind of lay out for us
real quickly the 3B mission and then what's beyond that.
-In terms of this, I'll do the science.
John can add the engineering part.
On the 1999 mission we'll be taking up to NICMOS ...
'99 mission which will now be the 2001 mission.
-Right. -The June 2001 mission
will have two major scientific advances.
One is the advanced camera for surveys,
which has a combined increase in capability
over the Wide Field Camera 2 of about a factor of 10.
In addition, we'll be taking up to NICMOS a cryocooler kit,
which if it works will restore
basically a dead instrument back to life.
In 2003,
we'll be doing the final servicing mission of Hubble,
and we'll be flying the Cosmic Origins Spectrograph,
which is a far more capable spectrograph
in terms of reaching very faint objects in the universe
than we've had before,
and we'll also be installing an insurance policy
for continued high-quality imaging
via the Wide Field Planetary Camera 3.
So having the advanced camera surveys put up there in 2001
and the Wide Field Camera 3 in 2003,
we should ensure our ability to take pictures with Hubble
through the 2010 planned end of life.
John, you want to talk about some of the other hardware,
solar panels, et cetera?
-Yes, and in this next coming mission after this one,
we plan to replace the solar rays
and to add some cooling capability
to the aft end of the telescope
so that we can run more instruments together,
and we cool those instruments so they don't get too warm.
That will get us even more science data
than what we've seen to date.
We're looking forward to that.
In the final servicing mission, we're replacing those batteries,
and then we'll have a fresh set for the rest of Hubble's life,
and the instruments and as Debby told you
in the final servicing mission, we'll change out all six gyros
to be sure that they last for the rest of Hubble's life.
-And obviously at the last possible minute,
which will probably be roughly a year or so
before the 2003 final servicing mission,
we'll take a close look at every piece of hardware on there
and see what we should replace
if we can to again do the best job
we can to keeping this thing going to 2010
because after 2003 there will be no other servicing missions,
and what we have is what we'll have.
-Clint Houston with Discovery News for Dr. Weiler,
do you still consider this mission an emergency?
-I don't think I ever called it an emergency.
It's not a routine-maintenance mission,
and it's not an emergency mission as NASA defines it.
An emergency mission for Hubble would be
where we are one failure away from losing the spacecraft.
Okay, we are not one failure away from losing the spacecraft.
We are one gyro failure away from losing science,
so that's called a ...
In our jargon, it's called a contingency mission.
So it's somewhere between an emergency
and a routine-servicing mission.
-We'll go to the Kennedy Space Center for questions now.
Go ahead please.
Give us your name and affiliation.
-This is Mike Cabbage with the Orlando Sentinel,
and I have a couple of sort of big picture questions
for Dr. Weiler.
First, could you put into perspective
where Hubble's contributions
fit into humankind's understanding of the universe
as it's evolved over the past millennium,
and secondly, why do you think Hubble's images have attracted
the attention from the public and the media that they have?
-Those are great questions.
Remind me to come back to the first one.
In terms of the public interest in Hubble,
I think it's something as basic as this.
Astronomy is unique science.
I've always enjoyed being an astronomer
as opposed to a chemist or a biologist
or a microbiologist, whatever, because the real people,
that is people who aren't scientists,
can appreciate what you do.
All they have to do is go out on a clear night away from cities
and look up in the sky and wonder a little bit.
If we can get them that far, they'll like astronomy.
You cannot ... No thinking human being can look up
at the sky in Arizona
on top of a mountain on a clear night
and not wonder about their place in all this.
How did he get there? Why is it there?
Are we alone?
That's what astronomy is all about.
These are not science questions.
How did it all begin?
How did we get here? Are we alone?
These are human questions, basic philosophical
human questions that people have asked
since the days that cavemen and women got up from the fire
and walked outside at night
if there weren't any saber-toothed tigers outside.
So that's why I think astronomy attracts people.
I think Hubble images because of the fact that ...
Well, first of all, they're the best images
ever returned to the universe.
Certainly, there's an added advantage
of not using black-and-white film
like astronomers used to use 20, 30 years ago.
Color does sell, and the fact that the universe is pretty big,
it has a variety of things that,
you know, some of them are very beautiful.
I mean, even pictures of comets hitting Jupiter
are beautiful in a sense.
They certainly make you think.
They put you in your place.
I mean, this could happen here.
It may have happened when the dinosaurs
were happily living here,
and a comet or an asteroid hit the Earth 65 million years ago,
and the dinosaurs disappointed along
with a lot of other things.
So astronomy teaches us about our past and teaches us
perhaps if we're smart enough about our future,
and in terms ... I forgot your first question.
I answered your second question I hope,
why does Hubble, you know ...
-In the context of the millennium,
how does this mission stand up?
-In the context of the millennium, I don't ...
Well, I thought the question was more of, you know ...
Well, let me ... Why don't you ask
your first part of your question again
so I don't answer the wrong question.
-The first part of my question was,
could you put into perspective where Hubble's contributions
fit into humankind's understanding of the universe
as it's evolved over the past millennium?
How does it stack up to ...
How do Hubble's discoveries stack up
against some of the discoveries from people like
Galileo, Kepler and Herschel as you look at the big picture
of how our understanding of the universe
has changed over the last 1,000 years?
-Well, that's a big-picture question,
and I'll try not to give you a big-picture answer
because it would take too long,
but first of all it's hard to compare Hubble to a Galileo,
to different instruments
because they're all part of the scientific quest
of understanding our place in the universe.
That's the one common theme,
what is our place in the universe,
and let me just use a little analogy
to try to put Hubble's stance in that analogy.
Back when humans first started thinking
when there wasn't TV and they actually, you know,
thought about things 2,000, 3,000 years ago,
they figured out that this universe,
these stars they all rotate around ...
revolve around the Earth,
and humans are the center of the universe.
Obviously, the universe was created for humans.
The Earth was at the center, and everything in the universe
rotated around it.
Well, a few thousand years later, along came that guy.
You mentioned Galileo and Copernicus
and Kepler and Tycho Brahe, and through their work,
especially when Galileo just had the nerve
to build a telescope and look at Jupiter
as one of his first targets, he saw little dots,
and they were moving around Jupiter.
Every night, they would be in a different position,
and when he plotted it out, they were moving around Jupiter.
This of course was impossible.
Right?
Well, it wasn't.
Things did move around Jupiter,
namely its moons.
Well, humans found another way to solve the problem
of having a special place in the universe.
We then admitted the fact
that maybe the Earth wasn't at the center,
but obviously the Sun had to be,
so we relegated ourselves just to being one planet.
However, the Sun was the most special thing in the universe,
and everything rotated around it.
To speed up the story, we found out that wasn't right,
that our sun was just another star,
but we made it a very special star
perhaps at the center of the universe, center of the galaxy.
We found out that wasn't right.
Our Sun was just sort of in the suburbs of the galaxy.
Then we discovered that there were hundreds
of billions of galaxies.
So here we were, just a lousy little star
on a little speck of dust
in a galaxy that's pretty darn routine in a universe
with hundreds and hundreds of billions of galaxies.
So what do we have left?
We've got the only solar system,
and most astronomers would have ...
Most people would have accepted that 50, 60, 70 years ago.
Well, then these ground-base
astronomers came along 3 years ago
and had the nerve to find that there were other planets
out there around other stars, in fact a lot of them.
Admittedly, they're not nice places to live.
They're five times the size of Jupiter, gaseous atmospheres,
too close to a star, too far away.
They weren't what Goldilocks would say
was just right like the Earth, but there were other planets.
So here we go again.
There are other solar systems out there.
What's the final thing we have?
And by the way, Hubble, that's where Hubble
has really played a major role.
The ground-base astronomers have actually found
some of these planets.
What Hubble has done is seen these planetary disks
around very, very many young stars,
so called protoplanetary disks,
and Hubble's role in that is showing that the process,
the process of creating solar systems,
the formation of solar systems is probably
very, very, very common.
In the Orion nebula, which is just one gas cloud
in our galaxy,
we looked at something like 56 young stars
a few million years old.
Half of those stars had these disks around them,
which may probably will form solar systems
someday in the future.
So what do we have left?
We're the only life in the universe.
That's the last thread we're holding onto
for our special place in the universe,
and if I can be so bold I will predict
if NASA continues to get a reasonable budget
for the next 10 or 20 years
we will build systems which will definitively show
that we are not the only life in the universe,
that life sprung up on other places.
Certainly, my kids, your kids will live to see that day
because I don't think that one star in 100 billion
in our galaxy,
one galaxy in 100 billion galaxies
is the only place that a few cells got together
and started reproducing.
Everything we know about biology tells us
that if you've got water, if you've got organic chemistry
and you've got energy life seems to find a way to form,
and we see that kind of stuff
every place we look in the universe,
those three things: water, energy and organics.
So I don't know if that answers your question,
but it was fun telling you about it.
-Robin Siriano with Florida Today and Space Online,
I have a couple questions about the insulation repairs
for John I guess.
Just how important are these repairs,
and if they couldn't be carried out for some reason,
do you have thermal concerns
that could lead to performance degradation or anything?
-Well, first, let me say on the forward part of the telescope
where that wallpaper goes that we can detect no change
in Hubble's operation.
That tells us that this insulation has degraded.
So we're really putting it on as a preventive measure
rather than as fixing a problem.
The insulation on the equipment base has degraded
and some of the components in those bays have warmed up a bit.
We could without a problem go through say until 2003
without having to do anything, and then the solution to that
if we could never fix that insulation
would just be to turn things off more often than we would like.
So right now, we're not affected by any thermal concerns,
and so we just want to prevent that,
and whatever insulation we are unable to put on
during this mission we can put on in the next mission,
and I don't think we'll be affected at all.
-Okay, thank you, and also for John,
you mentioned that two of the gyros are 14 years old
and have 4 to 6 years of runtime.
What is ... How old is the third one?
How much runtime does it have,
and what is the expected runtime out of one of these?
-The third gyro was installed during Servicing Mission One
in late 1993, so it must be 6 years old.
It's runtime is about the same.
Operating life, as explained by Debbie, is quite uncertain.
We have experienced that these gyros will run
typically from 4 to 6 years, but as we mentioned earlier
we've got experience with other spacecraft
where they can last much longer than that.
-Okay, thank you, and one last question from me for Ed,
I know you say it's not an emergency mission,
but I wonder how the launch delays might have increased
anxiety among scientists who are maybe a little concerned
because you are sort of running on your last legs
with these three gyros.
-I really can't answer the question
because I haven't detected any great anxiety.
I mean, there are so many other things to worry about in life.
You know, if we get up there in the next, you know,
couple weeks as we plan,
as I said, we're not going to lose any science at all.
If for whatever reason we'd have to slip until January
or February, you know, the odds are ...
Nobody can calculate the odds of whether the gyro
is going to fail or not, so it's a toss-up.
If we lose science, that'll be extremely regrettable,
but on the other hand safety of the shuttle is our number-one,
you know, number-one concern,
and until we're absolutely sure the shuttle is safe
we're going to, you know, risk a gyro failing on Hubble.
That's not even a trade-off.
-This is Phil...for John.
Let me follow up on Robin's question about the insulation.
What kind of concerns do you have of the insulation
if it flakes off?
Is there any serious concerns of any particular area
where somebody touching it wrong or something else
might cause it to flake off while you're surfacing,
and what's the worst-case scenario
if the insulation does get in either some optics?
How much would it affect performance
if something like that did happen?
-Well, first, let me say
that this degradation of the insulation
is because of the external environment.
The insulation that's inside the telescope,
inside the doors in the aft shroud is absolutely pristine.
There's never been any indication of any degradation,
and the astronauts were working back
inside the back of the telescope where the gyros
are when they installed the two instruments
in Servicing Mission Two.
So that's perfectly okay.
Now, we are opening the doors for the gyros,
and we're opening the door to put
the Fine Guidance Sensor in, but we're doing that
before we're doing any insulation at all.
So we'll have those doors open and closed,
the aperture doors closed.
So there's no reason that any of the insulation
could ever get inside the telescope.
-Okay, and a couple people,
I guess Ed and Ann, have both talked about the fact
that you're not improving science on this mission.
You're just improving the telescope.
Any thoughts about the fact that when it was launched
Hubble had five instruments,
and then with the First Servicing Mission it had four,
and now it's down to only two operational instruments,
the STIS and the WFPC2, about a third of the number
of instruments you had when it was launched?
-Well, Phil, I wish science were simple numerology, but it isn't.
You know, you should have asked me,
would I rather have the two 1990s
instruments I have operating now
or the original five 1970s instruments.
That's not even a trade-off.
The science capabilities of these instruments
we have up there right now and the ones we're going
to launch are orders of magnitude greater
than the old technology we had originally launched with.
You've got to keep in mind
the reason there's a renaissance in astronomy
is because there's been a renaissance in technology,
not just in computer technology
but in detection technology, etc.
The instruments we're flying now produce reams of data ...
If you remember John's chart
where we're now collecting ... What is it?
Eleven times the amount of science data
that we did in the early days?
So just saying we had five in the early days
and we only have two now is totally meaningless.
-Well, another way to address the question is to look
at the oversubscription rate of the number of astronomers
proposing per amount of telescope time,
and there's anywhere from five to seven times as many proposals
as there is time on the telescope,
and that number has only increased,
and I think that's also due to,
you know, the quality of the instrumentation
and the quality of the science
that can be done with a telescope.
-Okay, back you mentioned
the International Ultraviolet Explorer.
Back in the 1970s, we were able to launch a spacecraft
where a gyro switch could last 18 years and only failed
because they failed to be able to survive the budgets.
Why could we build gyros that were so good back then,
and we can't build gyros as good now?
I realize of course Hubble is much more precise,
and it's much more strenuous in a lower-orbit environment,
but it seems strange that expendable spacecraft
don't seem to have as many problems with components
as Hubble does.
-Go ahead, John. -Well, we used the IUE,
International Ultraviolet Explorer,
as an example because it's the same manufacturer
and the same class of gyro,
so what we were trying to communicate
was that sometimes a gyro can last for years and years,
and sometimes it'll fail early.
So that was the message that we were trying to get,
and it's the same class,
and in fact those gyros that were on IUE in fact
were improved to be quieter and more accurate for Hubble.
-Yeah, and the improvements that were made
to the gyros are unique. Remember.
Phil, I'm sure you know among all people
that IUE's requirements on stability were factors of 10
or even 100 less stringent than they are on Hubble.
These are the highest-tech gyros ever built.
They're one of a kind,
and you don't run those often on an assembly line.
-Okay, and I seem to remember when Hubble was launched
there were comments from astronomers
that it would be as much as of an improvement for astronomy
over Galileo as Galileo was over the human eye.
How much more of an improvement
does Hubble have now versus Hubble
when it was launched in 1990 in terms of performance?
Is there any way to quantify that?
-Well, again, the qualitative statement is still correct.
I mean, the analogy was based on the fact that the human eye
has about roughly 3 arcminutes of resolution capability,
and Galileo's telescope being crude
had roughly 10 times better than that,
and Hubble's improvement over a typical ground-based telescope
over the white field is about a factor of 10.
The mirror, the capability of the mirror on Hubble
is the same as it was in 1990.
The difference is the ability to utilize the photons.
The light from that mirror has increased dramatically
with the increases in ray detectors,
infrared detectors, etc.
When we launched Hubble in 1990,
we had spectrographs that had linear detectors.
They had 512 detectors all individual.
Now we launch spectrographs with 1,000-by-1,000 elements
or a million detection devices,
so the quantity of the science has dramatically increased.
The quality of the science,
the quality of the capability of Hubble
is the same as it was in 1990
in terms of its basic capabilities.
-Okay, we'll come back here to headquarters to wrap up.
First of all, we'll see if there are any follow-up questions
from our reporters here, and seeing none indicated
I think we'll go ahead and wrap up the briefing,
and I want to bring your attention to the screen.
We'll have a website listed there.
This is the new Hubble website for this mission.
Set your browsers and check that out.
We have animation pictures, interactive video.
We'll have daily mission updates during the mission
and links to the space-flight pages.
In addition to that, we have all of our fact sheets
and the media guide in that site,
so lots of good stuff there for this mission.
Thank you for joining us today and thank you, panelists,
and we're looking forward to the mission,
and the rest of the briefing is coming up later today.
Immediately following this or shortly thereafter,
we will have today's video file on NASA TV.