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Not every element that we use on NASA's James Webb Space Telescope

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Sometimes we use thigs that are tried and true

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and very abundant.

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Silicon it works!

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We don’t find silicon like this on Earth, it's pure form.

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It's usually paired with oxygen as a silicate and silicates make up 90%

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of the Earth's crust!

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Between 2010 and 2018, people purified

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7.37 million metric tons of silicon.

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2018's global revenue was $11.4 billion

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US dollars. What makes this element so special

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that the epicenter of the tech world is named after it?

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Let's head over to the shop to see why silicon works so well for this mission.

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So yeah silicon is cheap and available, but the reason

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we want to use it is because it happens to be a semi-conductor.

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Now a semiconductor is something that doesn’t conduct too well,

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like this metal object, or insulate things like wood would do.

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We want it to be able to do both, with a little coaxing of electricity.

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Mega coaxing

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A photo detector looks a lot like this, and its on a silicon wafer.

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And we use it because it has a stable atomic structure.

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When light passes on the silicon lets out a few electrons. That is the electrical voltage,

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which then translates into data

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for the scientists. Silicon isn't the only semiconductor

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or even the best semiconductor. But its ability to switch

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between giving an electrical signal or not, meaning a 1 or a 0

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makes it worth it.

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music