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[MUSIC PLAYING]

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The James Webb Space
Telescope is primarily

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an infrared telescope,
which means it has

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to be kept as cold as possible.

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The shape of the sun shield
helps it achieve and maintain

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those low temperatures.

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To find out just how
engineers on the ground

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are making sure that each
layer of the sun shield

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is built correctly,
we are here at ManTech

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in Huntsville, Alabama.

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So Jason, this is
the sun shield.

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What's so unique
about its shape?

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This 1/10 scale model--

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the sun shield from afar looks
like a flat piece of material,

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but it actually has a
doubly curved shape,

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which means it's almost a
funnel towards the center

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of the telescope.

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What we're about to see
is a full scale layer,

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and show you how we
measure that shape.

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There are five layers.

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Is each layer the same?

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No, actually each
layer is different.

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The layers are designed so
that we get maximum heat

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rejection between each
layer, all the way up

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to layer five on top.

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So that way, layer
one will always

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be the hottest facing
the sun, and layer five

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will be the coldest,
allowing the telescope

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to achieve operating
temperature.

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So you mean the shape of
each layer is different?

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Yes, actually it is.

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Great.

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So we can go check it out now?

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Yes, we can.

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All right, great.

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Over here, we actually
have one layer deployed

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in a flight-like simulator,
and it's tensioned to the loads

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that it'll see on orbit.

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So like you said,
it is not flat.

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No, it's not.

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You see, it makes
a funnel-type shape

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towards the center
of the telescope.

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Where Darryl is
standing, the telescope

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would be sitting right there
in the center, facing us.

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So what is he about to do?

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He's about to set
up a laser scanner.

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We use the scanning system
to measure the overall shape

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of the membrane.

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We actually do seven different
scans in seven locations.

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Each scan, one 360-degree
scan, creates about 407 million

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points.

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We combine those
seven scans together

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to get enough points to build a
solid 3D shape of the membrane

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to compare it to our
analytical model.

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Thanks, Jason, for
showing us just what

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you guys do to make sure the
sun shield is built correctly.

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Thanks, Mary, for
coming to see it.

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After testing here is
completed, the layer

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will be prepared for integration
with the rest of the sun

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shield.

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Thanks for joining us for this
edition of Behind the Webb.

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