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We are here at the Marshall Space Flight
Center in Huntsville, Alabama, known for its long history
in propulsion research.
But this NASA site is still a big player,
this time for the James Webb Space Telescope.
We're right outside the vacuum chamber
where the mirrors for the Webb Space Telescope
are being tested.
Back in the '90s, this facility was
used to test out one of NASA's great observatories,
the Chandra X-ray Observatory.
We have here the project scientist for Chandra,
Martin Weisskopf.
Can you tell us a little bit about the differences
between Hubble, and Chandra, and James Webb?
These are observatories that look
at different parts of what we call
the electromagnetic spectrum.
That is light at various different energies, from x-rays
where it takes a lot of energy to produce them,
to visible light where the Hubble Space
Telescope operates, and the near infrared where the James Webb
Telescope will operate.
In this way, by studying objects in the universe,
we can learn a lot about them that we
can't learn by just simply looking at one wavelength.
What kind of information can we glean from x-rays?
X-ray astronomy is the system that
brought the first discoveries of black holes in the universe.
So we look at very interesting astronomical objects
at very great distances.
In conjunction with Hubble, Webb will
be looking to identify many Chandra sources that
are not seen with Hubble.
Now we're outside the facility where the mirror
testing is being done.
And you can't help but see this long tube
that is connected to the building itself.
I'm told it's almost six football fields long.
Martin, what was this tube used for?
This tube is very important for separating the telescope that
was on the Chandra X-ray Observatory
from x-ray sources located at the other end of the building.
It has to be this length in order
to make those x-ray sources appear like tiny stars
so that we could determine whether our x-ray telescope
could distinguish small objects in the sky.
Why is it still here?
Chandra was tested in the mid-'90s.
It's still here because it's very, very useful
for many programs.
The vacuum chamber is being used to test the Webb optics.
And we hope to be testing x-ray telescopes in future programs.
Well, thanks for your time, Martin.
You're quite welcome.
The testing here for the Chandra Observatory
ran about six months, from 1996 to 1997.
Then the telescope was sent off to be
integrated with the rest of the observatory.
Chandra was launched on July 23, 1999.
Thanks for joining us for another edition
of Behind the Web.
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