[slate]
I like
to think of the James Webb Space Telescope as NASA's vehicle for the deepest
space exploration that humanity can do. We designed Webb to have a
larger mirror and infrared optimized system to see
farther into the universe than Hubble can today. This infrared
optimization also means that we can do things like peer inside dust clouds
in our own galaxy to see where stars and planets
are being born today.
[slate]
We start with the very smallest pieces we put together and we test
them in relevant environments. If they're going to be cold, we test them cold. If they're going to be
deployed we make sure they deploy. If they are going to
experience the violence of launch, and every piece of the telescope
will, we put it into a chamber and then on a shaker
table where it feels the same forces that it will through launch
So it's just a lot of testing. And as you build the telescope
up to ever larger structures, you test each of those as you
build it up. Right now at the Goddard Space Flight Center in the clean room,
they've taken the telescope through that vibration
testing and now they're measuring the optics. They're making sure
that the telescope optics and instruments are where they need to be
after they've gone through a simulated launch.
[slate]
You just have to keep testing
and retesting all the things that you expect the telescope
to experience. And so for us on Webb that means
we need to make sure it can survive launch. So we do vibration testing
at small component level, and as we build it up we test
that as well. Because we are what's called a cryogenic
telescope, meaning a very cold telescope, we put it into chambers
and take the temperature down to just a few tens of degrees above absolute zero.
So minus 400-degree Fahrenheit, and make sure all the parts
still work as they are planned to. And because we're so large
and we have to fold up to fit inside the rocket, we do deployment
testing. So we make sure our mirrors can fold out, and our secondary
mirror can fold down and the big sunshield can deploy.
All those tests have to be done several times on Earth
before we launch it into space. And then of course we also
mentioned earlier here at Goddard they're testing the optics of this
system. Once you have done some of these tests you want to make sure your telescope
and instruments still function like they're supposed to.
[slate]
I know for a fact that the science community can't wait to study the TRAPPIST system
with the James Webb Space Telescope. Last week I was at a science conference and
this very system was talked about how it would be
analyzed with Webb. So the science community is
ready to go for exoplanet studies with Webb.
So something like TRAPPIST-1 system and even other nearby systems
will certainly be among the very early things that Webb studies.
[slate]
Each of our mirrors, and there are 18 segments
is adjustable. We can move these segments left and right
We can move them in and out. We can move them around this way. And we can actually
change their shape a little bit. One of the lessons we learned
from Hubble is that you must put active optics so to speak,
so that you can make the mirror adjustable. So when it goes up we know we can
adjust it to be perfect after launch.
[slate]
Because we have such a very large mirror, one of the things we needed to do
is make sure that our mirrors had the right optical shape as
we changed their temperature from room temperature to the extremely cold temperatures in space.
So we had to develop measuring techniques that would allow us to do this,
and those very same measuring techniques have been commercialized
into machines that people will use to measure the shape of the
cornea of your eye. So if you were going to get laser surgery or
you needed measurements of your eye, you'd be using the same technology that we're
going to send a million miles away into space.
[slate]
Because we built Webb to really peer back to see the first
stars and galaxies and we've been working on it a long time for that, I really want to
see the answer back from that. But if I'm honest with myself
the thing that most excites me is that observation that somebody
makes that reveals something completely unexpected.
And that's what I'm looking forward to when somebody gets data back
and go 'I wasn't expecting that at all.' That's the real excitement of science.
[slate]
You can go to
NASA.gov or JWST.nasa.gov
and learn about the James Webb Space Telescope. There you'll find things
and links to videos and thousands of images of the telescope
descriptions of the science and even a little bit about
the people who are building the telescope and of course some of the fantastic engineering that's going
on as well.