So in the heat of the summer, these visors really can makes a difference.
rustling
And the Webb telescope uses the same
principle to block the heat of the sun and even what bounces off the Earth
and the moon. And just like my car's visor, the telescope's sunshield
unfolds, but its five layers are a little bit thinner.
A Tennis Court of
Carbon
This thin material is called Kapton and it makes the sunshield of NASA's James Webb
Space Telescope. So what is this strange Kapton?
It's a combination of carbon, nitrogen, oxygen and hydrogen,
but its primary element is carbon. It is only
1/1000th of an inch thick, that’s a quarter of the thickness
of the thinnest hair you can find. The five layers
of this reflective material will keep Webb cool and block the light the Earth
and Moon and our very bright sun, and each layer is the size
of a tennis-court. The sunshield happens
happens to be one of the most complicated parts of the telescope.
And that is because it must be packed like a parachute to fit into the rocket
and then unfold out into space.
Let's get a better idea at how good this Kapton is at
reflecting heat, I asked our resident expert in all things mini
to make me a 3 layered model of the sunshield using the same Kapton
that's on Webb. And then we put this tiny lightbulb to mimic
to heat source that would be the Sun, Earth or Moon.
See, you can see that heat reflecting off the bottom layer.
The Kapton worked so well that none of the heat is detected at the top of the model.
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The sunshield is capable of dissipating
500 degrees Fahrenheit over the 5 layers.
The heat radiates out from each layers that's why each layer gets a
little smaller from the bottom to the top
NASA actually uses Kapton for most its
It not only shields or contains heat,
it is electrically conductive. All that
shifting Kapton of the unfolding sunshield it could create static electricity.
But that charge wont build up on the Kapton and jump to the
observatory's super sensitive electronics. And then
Kapton's stability over a wide range of temperatures is why it is a great choice.
This modified version called mylar
mylar might even help you, if you get cold!
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