TRANSCRIPT
>> Welcome, everybody.
I'm the chief astronomer at the Franklin Institute in Philadelphia,
Pennsylvania and I'll be your host for our webcast today. Before
we begin, I would like to thank our sponsors for their generous
support of our program. They are the Northrop Grumman Space
Technology Center, the James Webb Space Telescope, Honeywell,
and the Planners Collaborative at the NASA Ames Research Center.
The Journey to Palomar is a wonderful film that’s premiering
on PBS beginning November 10th. Please check your local listings
for dates and times in your area.
The journey of Palomar is about the life and times of the most
remarkable scientists of the 20th century, George Ellery Hale. It
has been said that George Ellery Hale did for the entire universe
what Christopher Columbus did only for the Earth.
He built the biggest telescopes of the 20th century four times
over and in doing so it led to the greatest discovery since Galileo.
Because of George HALE mankind discovered the universe.
Most people have never heard of him.
His legacy, though, is also important because he paved the way
for his fellow astronauts, researchers and today's generation
of scientists.
Now today we're going to hear more about that from the filmmakers
of the journey to Palomar and learn about how NASA is planning
to use Hubble space telescope and other giant telescopes to find
water on the Moon.
We'll also get a preview of other giant telescopes of the future
that will work both in space and on the ground that will have
greater resolving power than even Hubble space telescope.
Now please go ahead and enter your questions into the chatroom
as we go along.
We'll also take questions from our audience at the Ames Research
Center and after we've heard from all our guests we'll look forward
to a lively discussion based on your questions.
Now I'd like to introduce you to the producers of the journey
to Palomar, Todd and robin Mason who will give you preview of
the new documentary.
>> Thanks, Derrick.
I think it's important to remember that before NASA took us to
the Moon, George Hale took all of us to the stars and did it
not with space ships, but with giant mirrors collecting lights
from the distant parts of universe.
He kept making bigger and bigger telescopes and finally it got
so big that the telescope required a mirror that was 17 feet
across.
It took 20 years to construct this gigantic telescope.
The mirror was so difficult to construct that just the mirror
alone to collect this distant starlight so they could look at
the distant parts of the universe took 11 years to polish and
grind to perfection.
If you were to enlarge the Palomar mirror to the size of the
United States there would be no bump or dimple more than two
inches.
A level of engineering thought to be impossible in the early
1930s when it was started and it almost was.
That's what we talk about in our film, amongst many other things.
But primarily our film is about George Hale and the difficult
life he led to overcome personal difficulties, challenges from
professional rivals and most importantly, the daunting engineering
challenges that kept bothering him his entire life but he kept
going and the film really is a celebration of the American can-do
spirit.
Robin has a few things to say about George Hale, too.
>> I was just going to add we spent the last several years
investigating George Hale's story and what we discovered is that
he spent his whole life building these telescopes.
The telescope that you see here, the Palomar telescope that Todd
was talking about was the last telescope that he built.
Before that he did it three other times that he built the largest
telescope in the world.
And so what that meant was that Hale's telescopes were America's
space program before NASA came along.
When NASA came along, their achievements were so spectacular
with the Moon landing and the space shuttle and all the other
amazing things that they've done that Hale's story kind of, you
know, has been forgotten over the years and it is really important
that we bring that story back because Hale's story is what led
to all the marvels we see today like the Hubble space telescope
and all the telescopes that we'll talk about today.
So we've brought today a short sample for you of the journey
to Palomar, the story of Hale's life and would like to take a
look at that.
>> George Hale built the largest telescopes in the world
leading to the greatest discovery since Galileo and .
This is the dramatic story of America's first journey into space.
With the new solar telescopes on mount Wilson, Hale dove into
his own research on the Sun.
The image created by the solar tower was the best anyone had
ever seen.
>> One of the famous discoveries that Hale was to make
was the Sun has a magnetic field.
That it's a giant magnet.
>> Hale's discovery of magnetic fields placed magnetism
in the cosmic framework.
>> I've been carried away by the solar whirl winds.
One day last week a solar prominence was drawn into a sunspot
within a few minutes.
The whole matter is so interesting that I find time for nothing
else.
Hale felt well enough to meet with Einstein to discuss why the
universe seemed to be exploding.
>> One of the motives was to settle this question of is
the universe expanding forever.
Will the expansion eventually stop or is there something more
sinister going on?
>> He studied pressures and temperatures and atomic reactions
far beyond anything possible on Earth.
Hale was offering the heavens, his price tag was $6 million.
The telescope would present the greatest technological challenge
of Hale's life.
>> Hale decided this telescope was going to be built knowing
full well that the way to do it wasn't yet known.
>> At 1 million pounds the Palomar telescope wouldway
more than 100 inch.
Massive supports of some kind would be needed.
The biggest problem was the glass.
He would have four times the surface area and eight times of
the mass of the 100 inch mirror.
When the glass giant finally appeared from the fog, the observatory
doors opened to accept the precious cargo, the telescope had
been waiting for nearly 12 years.
The astronomers had been waiting much longer.
>> Astronomy is an adventure.
Why are we here?
How big is the universe?
Of course we're only part way through answering many of those
questions.
>> Much of the universe remains a profound mystery.
The rate of expansion appears to be accelerating.
Most of the mass in the universe seems to be invisible.
The evolution of galaxies is only partly understood and life
elsewhere in the universe has yet to be detected.
>> Well, we hope you tune in to watch this broadcast.
It will be on PBS and you'll be able to watch it starting November
10th.
Now, some of the PBS stations across the country may air it at
a different date.
We know in Los Angeles it will be on on the 15th.
Check your local listings.
The name of the film is "the journey to Palomar" and
talk about what we'll talk about today.
>> It's about Hale.
It's a lot of fun in addition to being an important story.
I wanted to tell the teachers out there there is also a teacher
guide that accompanies the documentary and that will be available
at PBS.org slash journey to Palomar complete with images that
can be used in the last room.
The other thing I wanted to mention is the journey to Palomar
is based on a wonderful book called "the perfect machine."
It goes a lot more into the engineering details and things about
the Palomar telescope that we weren't able to cover in the film.
There is a lot to the story.
That's available in paper back from Amazon.com and I should mention,
too, this webcast will be archived after today at the same website
where you signed on for the chatroom and got the video feed so
you can watch it at a later time if you didn't get it to show
it to your class today.
Let me go back to Derrick and we'll take it from there.
>> Thanks Todd and Robin.
It sounds like an incredible story.
It looks fascinating.
Some of the key technologies used on Hubble space telescope were
first used on the 200 inch telescope that Hale built on Palomar
mountain.
In a few months NASA will mount a mission up to Hubble space
telescope for its final repair mission and the goal, of course,
is to keep Hubble active at least until 2013.
At that point, what will happen after that, well, there will
be a new telescope that comes along.
We'll get to that in a second.
The idea is to keep it working for a few more years.
NASA will use the Hubble space telescope in conjunction with
its lunar crater observation and sensing satellite mission to
look for water on the Moon.
Here is Brian Day of NASA Ames Research Center to tell us more
about it.
>> Thank you very much, Derrick, I appreciate it.
The story of the journey to Palomar is a story of the great telescopes
of the world and the wonderful things that we have learned
from them.
Now, many of the great telescopes of the world are about to be
used in support of our next venture to the Moon and what I would
like to do is take a few moments to show you some images here.
The exciting thing is yes, we are going back to the Moon.
We're planning to have a human outpost on the Moon in the 20/20s.
Now, one of the things you'll certainly want to have on the Moon
is water.
Water is important not only for drinking but making oxygen to
breathe, hydrogen for fuel.
It is a very versatile resource.
If we can find water on the Moon, that would make life a lot
easier.
Water is very heavy and expensive to carry to the Moon.
The problem is, every place we've been on the Moon, every place
we've landed, we've found the Moon to be very, very dry.
Almost no water at all.
However, some of our previous orbiters, the Clementine and lunar
prospector missions defected possible signs there may, emphasize
may, be water ice at the poles of the Moon.
Specifically we're looking at permanently shadowed craters at
the poles of the Moon.
At the poles of the Moon there are craters where the sunlight
never shines.
These places have been dark for billions of years.
They are very, very dark and very, very cold and may be places
where water ice could have accumulated.
So how do we find out if there really is water there and if so,
how much?
We will have two new robotic probes going to the Moon next year.
The lunar reconnaissance orbiter and LCROSS.
The Renaissance will study the Moon in fine detail.
LCROSS will excavate one of the permanently shadowed craters.
It will do this by using the two-ton upper stage of our Moon
rocket as than impacter.
That upper stage will impact the floor of the crater at 2.5 kilometers
per second.
That's about 5600 miles-per-hour.
Significantly faster than a speeding bullet but a whole lot heavier.
When it hits it will create a large plume of debris arching high
into the lunar sky.
The LCROSS mission actually consists of two components.
There is the upper stage of our Moon rocket that takes us out
of Earth orbit into the Moon and then above that built by our
friends at Northrup Grumman is the shepherding spacecraft.
It directs the centaur to its target at the Moon and carries
a number of instruments that will analyze the plume the centaur
creates and let us know what it's made out of them.
Both of them will launch together in 2009 aboard the same launch
vehicle.
Atlas V rocket.
It will take us out of Earth orbit toward the Moon.
Two hours after launch LRO will separate and continue on its
own path to the Moon.
LCROSS will remain attached to the centaur upper stage five days
after launch, we do a fly-by of the Moon.
That's not the end of our trip to the Moon.
That's just the beginning.
We use the Moon's gravity to sling us into a highly inclined
orbit around the entire Earth/Moon system.
Big, long looping orbits, 38 days for each loop.
The idea being that when we reencounter the Moon again, we'll
do so coming in at a very steep angle relative to the Moon's
pole.
About nine hours before we finally get to the Moon, we will separate
from the centaur.
We will perform a breaking maneuver so our robotic spacecraft
will pull back four minutes behind the centaur.
The centaur again will hit and excavate tons of material into
the lunar sky.
The LCROSS spacecraft will get a nice view of that impact and
over the next four minutes will descend directly through that
plume of debris sampling it and telling us what it's made of.
In addition, the great telescopes of the world located in observatories
such as up in Hawaii and the west coast will be observing the
plume as will the Hubble space telescope in Earth orbit and as
you'll see in the journey to Palomar, Edwin Hubble, who the Hubble
space telescope is named after is -- there is a spacecraft in
lunar orbit that will observe and study the plume that's created.
Here you can see the spacecraft actually being getting ready
at Northrup Grumman.
It's completed and awaiting transport to Florida for launch.
It is a very exciting time for us.
In addition, we think that amateur astronomers and people with
backyard telescopes will be able to observe the impact plume
so we're highly encouraging people to get out there and observe
and record this exciting event.
Students will also be involved in helping us track the spacecraft
and monitor its health and status while it's in flight.
To do this they'll be using the big -- some of the big dishes
at gold stone in conjunction with our partners at the Lewis center
for educational research.
Now, coming up here we have, as Derrick mentioned, a rather exciting
space shuttle mission.
We're going to be sending astronauts up to service the Hubble
space telescope one last time, make sure that it's working well
for the LCROSS mission as well as continuing to operate well
until it can be replaced by the next generation of great space
telescopes.
>> Thanks very much, Brian, that does sound exciting.
I know everybody will look forward to that.
I certainly will.
Maybe I'll have a chance to see the plume from our observatory
at the Franklin in Philadelphia.
There is another telescope coming along right after Hubble space
telescope that will move into position and we're about to see
a short video clip about that telescope, the James Webb telescope.
By the way, the clip that you're about to see and the rest of
the videos are part of a DVD -- part of DVD special features
from the journey to Palomar home video DVD.
Let's take a look at this preview of the James Webb space telescope.
>> The James Webb space telescope is the planned successor
for the Hubble space telescope launched in 2013 when the Hubble
is expected to be near the end of its life.
Both of these telescopes have extended the science pioneered
by George Hale by his great telescopes here on the ground.
We go into space because the Earth's atmosphere prevents us seeing
a certain wavelength and it's turbulent and we only get distorted
images through air.
Unlike the Hubble, the purpose of that is to enable it to get
cold.
When the telescope is launched it is all folded up inside the
top of the rocket.
When it reaches space and unfolds, the telescope will come out
and the Sun shade which has five layers will unfold.
The solar panels will unfold, the antenna will unfold and the
observatory will become a single giant telescope hidden behind
a five layer Sun shield.
In the end, the telescope will get down to 40 degrees -- minus
390 degrees Fahrenheit.
The new telescope will have a diameter of 260 inches corner to
corner across the giant hexagon.
The hexagon is made of 18 smaller hexagons.
After the mirrors are adjusted we expect to move them a few nanometers
every few weeks.
We chose ver millium for the mirrors.
It keeps it shape better when it's cold.
All these are difficult because the mirrors have to be extremely
lightweight so the things that we would do on the ground for
a telescope don't work in space.
We can't afford to lift that much weight.
If we were to build a telescope the way we built the Hubble we
have no rocket to lift it.
>> I would just like to remind our audience we'll be happy
to take your questions about anything you see during this webcast.
On the website you'll see that there is a location where you
can submit your questions that we'll be answering at the end
of this interview section and don't forget if you are in the
live audience there we'll also be looking for your questions,
too.
So get your questions ready and we'll be coming to you in not
too long.
With me here at the space flight center in Maryland is the science
director for the James Webb space telescope Dr. John Mather who
will tell us more about this amazing project.
Dr. Mather?
>> First I want to tell you about James Webb.
He was the second administrator of NASA and persuaded John Kennedy
to commit the nation going to the Moon.
He brought science into NASA and built up the university science
within NASA projects.
We owe him a debt of gratitude for his leadership.
Why are we building the telescope this way?
We need to look at infrared light which comes from the most distant
universe because of the cosmic red shift and objects like planets
not hot enough to have visible light.
The themes are all parts of our human quest to know how we got
here.
I wanted to know when I was five years old and my father could
not tell me.
The four parts that astronomers can work on first what happened
after the big bang.
We know it happened 13.7 billion years ago and the universe expanded
and cooled off and sometime later the first stars and something
else burned out in a hurry, three million years for each one.
This is a photo taken by the Hubble space telescope.
A time exposure that took us two weeks to get.
It tells us these beautiful galaxies are not the first objects
in the universe.
They would be too faint, too far away and too red to be seen
with the Hubble.
We need a telescope that can see farther away and fainter things
and capable of observing much longer wavelengths because the
expanding universe has stretched out the wavelengths they want
to see.
The next big question of how we got here is how did our own galaxy
form from the primordial material?
We have a simple story that small galaxies formed first.
It shows us what Hubble can tell us about the collisions.
Hubble cannot see far back enough in time to tell us how the
big things we see here got started.
We need the JWST to do that.
We have computer simulations that tell us what might have happened
but we just don't know.
There is one really huge mystery about galaxies.
Every one seems to have a giant black hole in the middle which
came first, did the black hole cause the galaxy to grow around
it and what happens when two galaxy collide and each one has
a black hole in the middle.
We hope to look far enough back in time to see the first steps.
The next big question for astronomers is how do stars like our
own Sun form?
The next picture shows what we think might happen.
But this is just a story, a concept.
Even though we have lots of equations we don't know.
We do know that it is happening right now at many places near
us in the Milky Way and we know that we can't see it directly
because it happens in dusty places.
The next picture shows us one of those dusty places.
This is the eagle nebula, one of Hubble's most popular and beautiful
pictures that shows brand-new stars burning near a dusty region
where they were born.
The dust is blocking our view of the cradle and we can't see
inside.
None of the things on that concept drawing that I just showed
you are visible inside that cloud so what are we going to do
about it?
We need to use infrared light.
This is taken with a big telescope on the ground in the mountains
in chili and it's different.
We can see inside the dust.
We still can't see the ones that are just beginning to grow.
For that we need the James Webb space telescope which will be
many times more sensitive than what we've had before.
That's because the things we want to see are too cool to emit
at wavelengths that will pass through the Earth's atmosphere
and ground-based telescopes are warm enough to glow at infrared
wavelengths.
You'll see pictures of some of these magnificent giant telescopes
built here on the ground but they won't be able to do what James
Webb telescope can do.
The next big theme for astronomers is what about the planets
and how is it that the Earth is capable of supporting life?
In the next picture I show one planet that is already close to
being detected directly.
This is an artist's concept of the star in the southern fish,
constellation in the southern sky and one of the brightest stars
in the sky.
The ring is off center.
The best explanation there is probably a planet there as big
as Jupiter or bigger and pulling the dust ring off center.
We're pretty sure the James Webb telescope will see the planet
directly and people are trying hard to see it even sooner.
We would like to know more about Earth.
We have two ways.
One is to study Earth-like planets around other stars.
We're getting closer and closer to finding them.
When we do some of them will go between us and their parent stars
and they will block some of the light.
They call this a transit.
We know we can see this happen with big planets and we've already
seen quite a few.
And we can begin to learn about the chemistry of those other
planets and maybe with some luck we can find signs of life on
another planet by this technique.
So to summarize, the James Webb telescope will be used to study
our own history by looking back at the universe from the beginning
to the formation of the first stars and galaxies to the formation
of our own solar system and the possibility of life right here.
Thank you.
>> Thank you very much, Dr. Mather.
I love the part about you wanted to know when you were five years
old yet your father couldn't tell you.
This expression of curiosity is one I'm sure that is shared by
many scientists and I suspect to a great degree certainly by
George Hale as well.
Now we'll learn--
>> May I interrupt you for a moment?
Our live classroom has lost connection.
We would like to take a moment to connect them back in if that
would be possible.
>> Sure.
That will be fine.
In the meantime while they're coming on board, as I was saying
I'm sure that curiosity is one of those aspects that has driven
you in your pursuit of science.
Would you say that's something that you find shared by most scientists?
>> Yes, I think it's shared by many people.
Most people are curious.
It is what makes us human and so wherever I go people want to
know how did this happen?
If we're here, how did that happen?
And mankind has been telling ourselves for many, many thousands
of years how did this happen but now we have some actual measurements.
We're beginning to look back in time enough to know.
>> When we look at this telescope itself, the James Webb
telescope I'm curious about the mirrors.
Can you tell us just a little bit about the mirror?
>> Yes, Beryllium is an unusual material to use for mirrors.
It's metal and extremely lightweight and tough.
We chose it because it works very well at very low temperatures
where the telescope will operate.
So it's the only technology that was ready to build this observatory.
>> These mirrors, though, when you say the temperature
for where this telescope is going to be located.
It won't be like Hubble that orbits around the Earth.
It will sit at one location?
>> It will be a million miles from Earth.
A good place for a telescope to get cold.
We can put up this strange looking umbrella you see in the picture
that protects the telescope from the Sun and Earth and let the
heat go to outer space.
>> An infrared telescope based on income a very cold location
so that helps to increase its sensitivity?
>> Yes.
It's what makes it special and why we can't do this observatory
on the ground.
>> This is a remarkable telescope.
I understand it's also quite large.
The Sun shields are enormous.
>> The shield itself is about as big as a tennis court.
It's huge.
Our telescope is 6 1/2 meters or 21 feet across, which is huge
for a space telescope.
It's about 2 1/2 times as big as the Hubble.
But it is still small compared with the telescopes we'll build
on the ground here and some already are twice as large as that
on the ground.
So ground telescopes have this huge advantage that we can build
them big.
>> Now, one of the interesting things about the mirror
itself as you said it's about 21 1/2 feet.
If I'm not mistaken that's a little bit larger than Hale's 200
inch reflecting telescope.
>> It's a little bit bigger but its major advantage is
it's in outer space where there is no air to bother it and it
can be cold.
>> We'll be able to control the telescope from Earth without
too much difficulty.
One of the things mentioned in the introduction there are fine
adjustments that will be made to the telescope during its operation.
>> That's right.
The telescope is launched in the condition where it's not a telescope
yet.
The mirrors are folded up and not in the right place.
After we launch it and deploy it and put all the parts in place,
then we have to adjust so that each one of those 18 pieces of
the primary mirror is actually in the right place to be part
of a single giant mirror.
We have the little motors and screws to do that.
>> Just wanted to let you know we have the classroom back
now.
Thank you.
>> Great.
Thank you very much.
So as I said now we'll learn more about the next generation of
giant telescopes on the ground.
Thank you very much, Dr. Mather for explaining the details about
the space telescope.
Everybody is interested in that.
2013 is the launch date for that?
>> Yes.
>> Fabulous.
There are other larger ground-based instruments that will continue
George Hale's scientific quest to understand the universe.
He founded the Carnegie -- the observatories of the Carnegie
Institution of Washington when he began his Mt. Wilson observatory
in 1904 above Los Angeles.
Today Wendy Friedman is the director of the Carnegie observatories.
They're building the guy--
>> One of the biggest questions that we're trying to address
with this telescope is following on the quest started by Hale
to look further and further back into the universe.
The giant telescope will be able to see back to the earliest
moments when we could actually detect the light from objects.
That is when the first stars would form, the first galaxies could
form.
The first black holes and with the giant telescope we'll be able
to witness directly those events.
Giant Magellan telescope is a 25 meter telescope, a segmented
mirror in the sense it will have seven giant segments.
It will be in the ANDES mountains in Chile.
300 nights a year are clear.
It's away from city lights and the atmosphere is very stable.
Astronomical seeing, very good sight.
The advantage of this design is that we can take seven mirrors
independently, each of which is 25 feet in diameter and allow
them to focus the light to a common point as a single telescope.
At the back of each of the mirrors, there are a series of what
are known as actuators that can put a force on the back of the
mirror to change the shape of the mirror and it can do that on
very short time scales.
There will be 4,000 of these actuators for the entire giant Magellan
mirror.
We have a secondary mirror so the light bounces off the primary
and hits a secondary mirror near the top of the telescope.
The secondary mirror is also composed of seven smaller segments,
each one of which will correct the light from each of the primary
mirrors.
It's in this way we can achieve a resolution ten times that of
the Hubble.
The challenge of the 1980s was coming up with a way to make mirrors
that would be more lightweight than the mirrors at Palomar.
One of the ways that was done to do that was to create an oven
in which to cast the mirror.
An oven that is spinning.
You take chunks of glass, put them into the oven and then as
the glass is melting, you get the parabolic shape of the mirror
that you want.
Then unlike Palomar where you had to grind off much of the glass
to get the parabolic shape of the mirror to bring the light to
a focus, much of that has already been done for you.
What that gives you in the end is a lightweight mirror.
Much lighter, for example, than the mirrors at Palomar which
is solid and it lets you control the temperature of the mirror
very accurately which leads to stability of the mirror and better
resolution and focus.
>> As we view these programs segments I would encourage
our audience, when the program comes on, to think about how George
Hale might have felt if he could be here today to see how these
mirrors are created.
Let me take a moment to remind our audience we'll take your questions
online at the website and we'll also take questions from the
audience so those of you that are in the live audience get your
questions ready and those of you listening online if you're right
there at the website you'll find there is a space for us to take
your questions.
Be sure to get them ready and submit them there so we can have
a lively discussion session after we're done with the major portion
of the webcast here.
Joining us now from the jet propulsion laboratories in Pasadena,
California is Dr. Wendy Friedman to tell us more about the giant
Magellan telescope.
Dr. Friedman.
>> The giant Magellan telescope will have 20 million times
the light collecting power of the human eye.
A staggering step forward.
It will have seven primary mirrors.
As we heard this telescope will be over 80 feet in diameter so
it's a remarkable step from the first telescopes of George Hale
and in answer to your question, Derrick, I think he would be
quite thrilled to see the progress today in astronomy with Hubble,
James Webb and our new generation of telescopes.
Hale was very interested in stars himself.
He was interested ultimately in understanding the nature of stars,
how they might evolve.
Where the chemical elements might have come from.
With the discoveries of Edwin Hubble early in the 20th century
we began to learn the universe is a very dynamic place.
There are other galaxies in addition to our own Milky Way galaxy
and the universe is taking part in a giant overall expansion.
Those discoveries which were not even imagined before Hale set
on his quest to build the telescopes revolutioned the nature
of the universe we live in.
The next generation of telescopes we know we live in the Milky
Way galaxy not dissimilar to the galaxy behind me but we don't
know how those galaxies assembled.
There is a period in which literally we know nothing.
Our knowledge of the universe ends, Hubble can take us so far
and we can learn about the earliest moments of the universe after
the big bang say about 400,000 years after the big bang but there
is a period where we have not yet seen back and witnessed directly
where galaxies are forming, where the first black holes form
and so on.
And these new generation of telescopes will allow us to do that,
to witness these events directly.
We also didn't know even a decade ago, just over a decade ago
was this discovery of the first planet outside of our own solar
system.
And 400 years ago this year coming up 2009 marks the year of
astronomy.
We thought at that time that the Earth was the center of the
universe and in the last decade what we've learned -- I'll come
back to the nature of our position in the universe.
What we have learned is that the planets in addition to those
in our own solar system.
And in fact there are a few hundred of those and climbing.
We still haven't discovered planets that are similar to the Earth.
Our current technology allows us to discover planets like Jupiter,
Saturn and the more massive planets in our own solar system and
now we're finding planets that are similar to a fraction of the
mass of Saturn and Jupiter but we have not yet been able to detect
planets like the Earth.
That's coming in the next few decades.
I think the people in the audience today, kids in school today
are going to be present for the discovery of the first planets
that are like the Earth.
If we're lucky and some of these planets are close enough, then
some of the telescopes that are on the drawing board today like
the giant Magellan telescope will be able to directly image planets
like the Earth.
We may even be able to learn something about their atmospheres,
whether or not there is carbon dioxide and water, perhaps ozone.
The signatures of life.
I think there are a few discoveries that tend to be revolutionary
types of discoveries.
The discovery of galaxies other than our own Milky Way and the
expansion of the universe.
The ideas that led to a big bang picture of the universe being
an example.
The discovery that the Earth is not the center of the universe.
The idea that came -- in fact, took until 400 years ago until
it was accepted that the Sun is the center of the universe.
These kinds of things are not just interesting to astronomers
and scientists who study them but I think profoundly affect humanity
and our perspective of the universe in which we live in and allow
us to ask questions about how this came to be.
And I think there are other discoveries out there yet to be made.
One of which is the discovery of life on other planets.
I believe it will be that kind of revolutionary discovery.
Now, I want to say a couple words because I know there is an
audience of school kids out there.
I would guess that half of those kids are girls in the classroom
statistically and I would just like to say to the young people
in general, not just the girls, maybe particularly so because
when I went to school I wasn't encouraged to go into science.
I can tell you it amazes me that I have a job today where I get
paid to do what I love to do.
I think the audience that's sitting there today watching us talk
about these future generations of telescopes that will take about
a decade to build, many of them, you will use those or you will
have the opportunity to use those facilities and we can't even
imagine the kinds of discoveries that those telescopes will make
in the same way Hale couldn't imagine what would come out of
the telescopes he dreamed of.
I had a high school teacher 10th grade and he used to say any
time he would discuss a complicated subject, physics, the girls
don't have to listen to this.
Now, my impression is the school systems have improved and I'm
hoping you aren't receiving that message.
But what I can tell you is that if you follow your interests
and if those interests happen to be science and particularly
if they happen to be astronomy there is a rewarding future out
there for you.
So thanks.
>> Thanks very much, Dr. Friedman that was really well
said.
That last part in particular.
I know a lot of us look forward to the discoveries that will
be made with a telescope like that.
It's amazing that the combined mirrors will be the size of a
parking lot.
80 feet in diameter.
That's enormous.
Great science to be learned with an instrument like that.
George Hale was also the driving force behind the founding of
the California institute of technology, Cal tech in the teens
and 1920s.
Caltech owns and operates the Palomar observatory and the observatory
in Hawaii.
They're now planning to build a new giant ground-based telescope
called the 30 meter telescope.
Its mirror will be nearly as wide as a football field.
Let's have a look at the video to see what that one is about.
>> Imagine yourself now in 2016 being invited to the opening
ceremony for the 30 meter telescope and let's imagine that you've
been to see it.
The first thing that will hit you, it is a larger dome.
But not that much larger.
What is greatly different is the telescope occupies a much bigger
fraction of the dome and the mirror is enormous and it will hit
you in the face because it's such a huge mirror.
The mirror is 100 feet in diameter.
The overarching them for the 30 meter telescope is the history
of the universe.
It sounds simple but really we're looking at understanding the
origin of the universe, how galaxies like the Milky Way formed
for the first time and assembled.
How more complex molecules developed in space that leads to life
forms.
So it's a very grand but incredibly fundamental quest.
The 30 meter telescope is a reflecting optical near infrared
telescope which has a reflecting primary mirror that is segmented
with 492 individual segments that combine to make a 30 meter
aperture primary mirror.
The light is reflected from the sky through a 300 meter secondary
mirror and a third mirror which can rotate to reflect the light
to any one of a number of instruments.
On the 200 inch we're talking about instruments of maximum weight
one to three tons.
Here we're now talking about instruments that potentially 20
to 30 tons or so.
The departure to a segmented mirror telescope was inevitable
when we got up to the 8 to 10 meter class level.
We'd never be able to make a 20 or 30 meter piece of glass.
It's difficult to support and we wouldn't maintain the curvature
over a large area and it would be impossible to transport.
Probably the most challenging aspect of the 30 meter telescope
is the correction for the blurring in the Earth's atmosphere.
This is a technique we call adaptive optics.
It is already in regular use on our existing telescopes and the
way it works is we take the light from an image.
Either a star or laser reflected off layers in the Earth's atmosphere
and use the signal to monitor the turbulence in the Earth's atmosphere.
Now the Earth's atmosphere doesn't behave in a very cooperative
way.
It certainly is possible to make this correction along one line
of sight but if you want to correct a cone of light coming through
the atmosphere, then you need a number of lasers.
Each shining off different parts of the atmosphere to create
a correcting signal that can be applied to recover the true resolution
of an object as if the telescope was in space.
>> That sounds remarkable that this telescope will be
so large.
If you think about the size of this telescope, 100 feet across,
30 meters, that's just about the size of a ten-story building.
The mirror will be as wide as a ten-story building is high.
Joining us also today from the jet propulsion labs in Pasadena
is Dr. Richard Ellis.
The steel professor of astronomy at Caltech and here to tell
us about what the work is going to be done with the 30 meter
telescope.
>> Hello, everybody.
As you might detect from my British accent I crossed the Atlantic
eight years ago to get involved in this very exciting project
the 30 meter telescope.
Those of us working on the 30 meter telescope feel every day
we're following somehow in the footsteps of George Hale.
But there are some differences between the 30 meter telescope
and the telescopes that Hale developed.
What I would like to do is first tell you what the differences
are and then explain the excitement of the 30 meter telescope
and what it might see.
So for much of the 20th century Hale's motive was building a
bigger and bigger mirror.
He did this relentlessly through the whole of his life as you'll
see when you watch the PBS broadcast.
We heard he raised funds successfully for a 60 inch, 100 inch
and the 200 inch telescope at mount Palomar that was named after
him and was director until quite recently.
That telescope is still in operation every night conceived in
the 1920s it's celebrating it's 60th anniversary next year and
still doing front line research.
It illustrates a telescope on the ground is a lasting research
instruments that last for decades.
The very first significant change from the telescopes that we're
going to be using today and in the future compared to the telescopes
Hale developed follows the ambition of a remarkable scientist
Jerry Nelson at the University of California.
In the 1980s Jerry Nelson had the brain wave we could make a
large mirror from many independent segments.
This is an extraordinarily risky Endeavour at the time but led
to the twin telescopes in Hawaii recently the largest telescopes
in the world which are being very successful.
Basically the twin telescopes in Hawaii have, among other things,
led to discoveries that the universe is accelerating.
They found more extra solar planets than any other telescope
and it's a tremendous excitement to use one of these very big
telescopes to make discoveries.
I was observing with one last week and it is a tremendously exhilarating
experience to use a very large telescope.
Think of the potential every night of making discoveries.
Well, the 30 meter telescope will extend this idea of building
a large mirror from many numerous segments as you saw in the
video.
Will have 492 segments instead of the 36 segments.
It leads to the ease of manufacturing a large primary mirror
made up of many articulated segments that all have actuators
so the surface of the mirror can be carefully maintained.
There is a second difference, as you saw in the video, between
the telescopes that Hale realized and the telescopes we use today
and the 30 meter telescope.
That's the optics.
This is the technique for correcting for the blurring in the
Earth's atmosphere so we can realize on the ground the resolution
that we would have if a large telescope was in space.
Now just as an aside I would say to give Hale credit 100 years
ago in 1908 he wrote an article where he speculated what would
be the biggest telescope that would ever be built on the ground?
What would limit the size of a telescope?
Would it be engineering?
He thought not.
Actually he thought that the limiting factor would be the resolution
of the telescope which would be affected by the blurring in the
Earth's atmosphere.
Hale might have stopped at this point but he went on and wrote
that if by some means we could correct the blurring in the Earth's
atmosphere astronomers would have other fantastic discoveries
they would be able to make.
The key point about the 30 meter telescope is we're now at that
exciting point.
Adaptive optics is here, it's routinely used on our telescopes.
We shine a 20 watt laser into the sky and it reflects off a layer
of sodium atoms high in the atmosphere to create an artificial
star.
That artificial star gives us a measure of the turbulence in
the atmosphere as the light from the star comes down to the telescope.
So we're really able to make these corrections and this is just
the beginning because with many lasers we can correct areas of
sky to study not just one object but a number of objects.
For example, distant galaxies to see if they're spinning and
rotating and evolving into systems like our Milky Way.
The 30 meter telescope will be the first launched telescope to
have adaptive optics in the onset.
This is taken prominently in how we design the telescope.
It's excellent image quality will enable us not only to resolve
distant galaxies so see how they're revolving but allows us to
look at faint objects near very bright objects.
In finding Earth-like planets around cool stars.
Now, as Wendy mentioned, one of the most exciting things about
the next generation of telescopes is the things that we can't
even appreciate at the moment.
It's amusing to go back to 1980 and look at what we thought we
would do with a cath telescope and it is quite incredible how
much better we've done than where we predicted we would be.
For example in 1980 we imagined that a 10 meter telescope would
see out to only about 8 billion years in look back time.
8 billion light years where we're looking at objects much more
distant than that.
We did much better than we predicted we would.
The accelerating universe, the identification of gamma ray bursts,
giant particular explosions when black holes and new stars emerge.
The 30 meter telescope, the design is more or less complete.
We have a construction proposal.
Of course, this is an expensive facility.
Hale would realize the challenge of raising money for these very
big telescopes.
We've just got a very large private donation to enable us to
move forward towards a partnership that will lead to the construction
of this telescope.
It is an exciting adventure.
It is very different to working with a space observatory.
A large telescope on the ground is a lasting achievement.
One that you can adjust with new instruments over decades to
come.
So I'm confident the 30 meter telescope will still be in use
50 years from now and I'm very confident that many of you in
the audience will one day use it to make great discoveries.
Discoveries that we can't even imagine today.
That is, of course, the excitement of astronomy and why I became
an astronomer.
Thank you, Derrick.
>> Thank you very much, Dr. Ellis.
What sounds exciting to me about that is the use -- the way in
which the telescope is being designed with adaptive optics
in mind.
The idea of sampling the atmosphere in order to make use of a
way to make the atmosphere disappear in a sense and give us these
really great images from Earth.
That's really fantastic.
With this incredible introduction to the future of ground and
space-based astronomical observing in the future I'm sure there
are quite a few questions that you, our audience, would like
to ask our experts here.
So please get your questions ready if you still have a question
online, you can enter your questions into our chatroom and those
of you in the audience, we're going to call on you to -- with
your questions so we can get a little conversation going here.
Your questions are going to be the basis for our conversation,
if you have questions, now is the time.
Let's see, who do we have in our audience today with a question?
I'm sure there is a hand out there somewhere.
Or do we have questions online from the chatroom?
>> Let's start maybe with that.
I have a question here that I like very much from Peters ward
it looks like.
Can we ever look through one of these telescopes?
>> That's a great question.
Wendy, would you like to pick that up?
>> Sure.
Well, we have currently at our site in the ANDES mountains in
Chile called the Magellan telescope that preceded the giant
Magellan telescope.
We have an eye piece we put on that telescope.
It happens only once a year.
>> Ooh.
>> It's not the regular way that astronomers make observations.
That's what Galileo did when he turned a telescope to the sky
he actually looked through with an eye piece and now astronomers,
of course, use first photographic plates and now digital detectors,
not unlike the detectors that we have in digital cameras.
It's an unusual treat to look through a Magellan telescope.
I can tell you firsthand it is one of the most exciting things
that I've done as an astronomer.
It is very interesting to me because we take a group up there
the night that we do it and most of those people are not astronomers.
They are thrilled also but it is the oohs and the AAAHs of the
astronomers in the group as they see the rings of Saturn and
the moons of Jupiter and the glowing areas of gas around objects
when the stars are forming.
We actually see colors.
So in principle, yes, it's possible but very rare.
Most of us don't get that opportunity these days.
We sit in a room.
We see what comes on our computer screen.
So it's not as exciting as it used to be but it is still exciting
nonetheless to see it on the screen.
>> Dr. Friedman.
You have to sign me up for one of those nights please, oh please,
oh please.
Another question?
Other questions from online perhaps or maybe from the audience?
>> Derrick, from here at aims we did want to add a little
to that answer.
>> Great.
Please do.
>> I just wanted to mention to the students that if you
ever happen to visit California or if you live in California,
you can visit Hale's observatories at mount Wilson and at Palomar.
At Mt. Wilson it's set up so you can actually arrange for a time
on the 60 inch telescope, once the biggest in the world built
in 1908.
You spend an evening looking through the 60 inch telescope.
If you're ever out here or you're with a group and you can do
that, you can go to their website Mt. Wilson observatory and
arrange to do that.
>> When you look through the 60 inch telescope at Mt.
Wilson you can see galaxies from 60 million light years away.
The skies around us are maybe a light year or four light years
away, very close by comparison.
Even our own star is eight light minutes away.
>> Okay.
I understand that our classroom is now on.
>> The live classroom is about ready to ask a question.
>> Let's go ahead.
>> When we find a planet like ours in another galaxy with
I'm guessing life on it, what do you think the government's reaction
will be?
Do you have a plan for this?
>> Let's see, Dr. Mather, would you like to take a stab
at that?
Thank you, that's a great question.
>> Let me think that will be a very exciting time for
whoever does it and I think that we'll have an incredible public
interest in that.
I think it will be hard to plan.
That's such a kind of discovery that will be world changing for
many people and it will be like the discovery of a new continent
for many people.
So I can't imagine how we could plan for it.
Of course, we will.
We will, of course, be planning for the discovery of planets
we know we're looking for.
We can't be sure what we'll do when we find something new.
>> One of the things we better do is encourage the students
here to help us figure out how -- what the reaction of the government
will be since it will probably be in your not too distant future.
Thanks, Dr. Mather.
Is there another question?
>> I was wondering, what is the cost going to be for this
building of these new telescopes and how do we get all these
fundings for the telescopes?
Building all the telescopes?
>> Thank you very much.
Dr. Ellis, you talked a little bit about the cost and you also
hinted that there was some funding already available for the
30 meter telescope.
How will we fund these instruments?
>> Like George Hale, this is the big question and he spent
a lot of his life agonizing over how to find money to build the
bigger and bigger telescopes the history of his career.
The 30 meter telescope.
The answer to the question is it's a billion to build the telescope.
That's a lot of money in any body's book especially at the moment.
The way in which we go about raising this kind of money is we
build a consortium of interested groups of astronomers.
In the case of the 30 meter telescope we have the country of
Canada, Japan, the University of California and Caltech and each
of these is to either raise money through private means or, of
course, go to that government to raise the money for the capital
to build a telescope and eventually to operate the telescope.
Even when we build the telescope, we have to find the money to
pay for electricity, to pay the salaries of the people who work
there.
This is a big challenge.
Of course, the way we go about this is we have to write a spectacular
case of all the discoveries that we expect to make and so both
Wendy and I spend a lot of our time agonizing over how to find
money and writing more and more proposals.
We go back and look at what Hale did, this is exactly how Hale
was working in the 1920s and 1930s.
>> Are there any other magic ways in which we might be
able to dig up some funding?
Wendy, is there a secret stash someplace?
>> I think one of the interesting things about astronomy
in comparison to other fields in science is actually within the
public at large a lot of enthusiasm for astronomy so there has
been some history of individuals who have actually put funding
from the private sector into astronomical telescopes.
It is not that other sciences aren't interesting also but there
is a tremendous visual appeal.
A lot of the questions astronomers ask are questions that resonate
with the public.
We've been fortunate for a century now at left under George Hale
in the beginning when he began his quest to build the large telescopes
to get support from people in the private sector and we've been
very fortunate to get that also today.
I think these questions that we're asking are exciting questions
not just in the U.S. but as Richard says, we have collaborators
now in other countries, the GMT has a partner in Australia and
we're looking at partners elsewhere around the world.
Also within universities.
And so I think while it's not easy, I don't want to minimize
the challenge, there is enough excitement about what we're trying
to do that I think we'll ultimately succeed despite the sticker
shock of the price tags.
>> Great.
Thank you.
I think we have time for one more question from the floor.
Is there anyone else in the audience there that has a question?
>> My question is in 1929 astronomer Hubble discovered
that the earth was expanding.
How fast would it be expanding if it was expanding?
>> Let's see.
Who will take that question?
Dr. Mather?
>> He discovered the evidence that the universe is expanding,
not just the Earth.
The Earth is not expanding actually but he was able to see that
just the nearest part of the universe is expanding quite rapidly
at thousands of kilometers a second distant galaxies are going
away from us.
If you go out to the most distant galaxies he seems to be almost
the speed of light we can Segal action east going away from us.
Whatever happened in the early universe to make this happen is
one of the great mysteries that astronomers hope to tackle so
it's extraordinarily fast and we can barely imagine it.
>> Thank you very much.
It is remarkable to think about the fact that the universe can
expand in that manner.
Is there another question from the floor there?
>> So my question is, are there any telescopes that can
detect gravitational waves instead of light waves?
>> Wow, that's a fantastic question.
>> Who would like to take that question?
>> I'm happy to take it.
Wendy, I don't mind.
>> Go ahead.
>> The answer is yes, there is a telescope operating at
the moment called LIGO.
A collaboration between Caltech and Massachusetts institute of
technology and other schools.
It's different from what we've been talking about today.
To detect gravity waves.
A gravity wave is an event in the universe where, for example,
two black holes merge and create a ripple in space.
That can only be detected if you have a very carefully precisioned
rod of metal that is sensitive to very, very small vibrations.
So if you can imagine having a long rod and then watching this
rod vibrate and making sure that that vibration is not caused
by a truck going past on the freeway or some other earthquake
or seismic event this is how we will detect gravity waves.
There are a number of observatories around the world.
The one in the United States has been operating for just over
a year and being upgraded as well.
We hope to be able to detect gravity waves in the next couple
years or so.
That will be an amazing discovery in itself.
It's an important proof of Einstein's theory that we see these
gravity waves.
>> In a very real sense we've been able to look at light
waves and this is now actually sound, hearing in some sense the
universe.
It is a completely new window on the universe that is opening
up.
>> Thank you both very much.
That was an excellent question.
Thanks to that student for asking that question.
Let's take a couple of questions now from our chatroom.
Is there -- let's have the first question from the chatroom,
please.
>> We have a lot of very good questions in the chatroom
and I'm going to select a couple.
Fifth grade student asks.
How will they get the JWST in such a high orbit and how will
they service it if they do have it up in such a high orbit?
>> That will be Dr. Mather.
>> The European space agency is contributing the launch
vehicle.
It will be a large commercial rocket launched from French Guyana
in the equateer in South America.
It goes too far away for us to service it with our currently
available capabilities for astronauts and robots but we'll put
an attachment point on if we're ever able to send a servicing
device out there.
>> It will be out there not exactly autonomous but at
such a distance we can't get there to serve it.
>> We plan to make sure there are redid you know Dan sees
in it.
Extra pieces of equipment if anything would go wrong and that's
our backup plan for it in case of small mistakes.
>> Sounds like it would be a long trip for a repair team
to get out there.
Thank you.
Next question from the chatroom.
>> Did Mr. Hale have many problems working out any aberrations
in the optics of his telescopes and if so, what kind and why?
>> Hale's entire -- I was just going to say.
>> Hale's entire life was spent struggling with glass
and his very first telescope just north of Chicago actually used
a lens.
We haven't talked about lenses much here today but the telescopes
in the 19th centuries used lenses where the light would go through
it like a giant magnifying glass.
That lens was 40 inches across and had to be ground to such perfection
one of the critics said the deviation of the width of a spider's
web would have been enough to cause the glass to not work.
They were worried about it.
It did work.
You couldn't make a lens bigger than that because it would sag
under its own weight and why the technology shifted to mirrors.
It collects the light and focuses it to a point and down to a
camera.
Each of the mirrors posed tremendous problems for George Hale
and each of theme created engineering difficults that no one
could anticipate.
Hale had several nervous breakdowns.
Hale didn't survive the process of the Palomar mirror.
He died ten years before the telescope was finished.
That's a big part of the story you can see on the PBS film.
>> That's what our story is about is all of the difficulties
that he had to overcome to build these giant telescopes.
It was one difficulty after another.
As Richard said in the film, Hale decided he would go ahead with
these projects nothing full well the way to do it wasn't known.
They had to invent the technology to make this happen.
I think that's been a long tradition with NASA ever since is
to attack things with optimism even though you don't know how
you're going to make it happen.
So yes, and you'll see all of that story in our film.
>> Unfortunately we've run out of time for this webcast.
I would like to thank the film producers Todd and Robin Mason.
All of our guest experts as well as our student audience for
joining us today.
If your question wasn't answered today.
Just come back.
I want to say I want to encourage the students to come back to
the archive section of this same website within a few days and
they can find an answer.
Robin, did you want to say one last thing?
>> I was going to mention if your question wasn't answered
we'll do it online and you can come back and check it later.
>> Just a few days you can come back and check on the
same website.
Don't forget to watch for the journey to Palomar on your local
PBS stations beginning November 10th.
Check your local listings for the time and dates and you can
learn all about Hale and the amazing giant telescopes he built.
The most extraordinary scientific instruments of the 20th century.
Thank you for joining us.
So long everybody.
