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It is pretty fitting that these are called cosmic flames.

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These packets nothing but a bunch of different

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Lithium makes red, barium makes green and so on.

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And then they in these really pretty colors.

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Burning chemicals is a legitimate way to find out what something is. Chemists

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call it the “burn test”. All elements actually give off a signature when

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they are put into an excited state.

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Here we are witnessing what happens in a fire. The James Webb Space Telescope will be able to read

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the same signatures from unknown stars and planets.

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How Does

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Webb Seek Elements?

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I’ve been taking you through different elements that are built into the Webb Telescope

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Gold reflects infrared light well

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and will not corrode, beryllium is lightweight,

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silicon is a tried-and-true semi-conductor.

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Isn’t it just poetic, that Webb is designed to detect elements?

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Webb uses

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a device called a spectrograph, it works by splitting light, with a prism.

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We can tell what element we see based on the pattern from the

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light through the prim. Every element releases light at a

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different wavelength. When the light is split by a prism, black bands appear

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due to the transition between energy states – these are called

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absorption lines. The lines always appear in the same part of the rainbow

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which is why we call them “atomic fingerprints”.

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I’ve made my

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own simple spectrograph to give you an idea of what Webb sees.

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And the object that makes it work is this relic

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of technology – It’s a CD!

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CDs and DVDs

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use the same principal as another ancient devise – the record.

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They use tiny tracks of bumps to convey information.

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Records are 3-D representations of the sound and a CD uses

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raised binary points.

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The point is that these discs have a very fine groove pattern that physically

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splits light – that’s why they have a rainbow or iridescent color.

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Webb’s spectrograph also uses really fine grooves to split light.

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The Near Infrared Spectrometer, called NIRSpec is designed to take

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spectra for up to 100 objects at once!

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usic

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You don’t need to go all the way to space to see the spectra for different objects

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my little homemade spectrometer can tell me

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what the primary element different light sources use.

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Neon lights get their name, because the light

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uses neon gas to get its color.

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Actually, the neon only refers to the one color,

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these types of lights use other gases make more colors.

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Let me show you the fully spectrum of colors

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that we can see based on a combination of these

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different elements.

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Webb’s spectra really give more information than just elemental makeup.

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They can also tell astronomers about the temperature, mass

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speed and density of the objects as well.

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All elements have a cosmic start. Smaller elements

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are forged in the heat and pressure of a star.

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Anything larger than iron, needs the powerful force of a supernova,

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or colliding neutron stars.

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These elements may stay as dust clouds or eventually coalesce

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into asteroids or new planets characterized by their original elemental makeup.

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The spectra Webb will see not only tells us what elements we’re

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looking at but the warmth and density of the bodies as well.

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So we might detect some distant bio signatures!

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Webb’s build may use a scarce element like beryllium for its mirrors,

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but will that cosmically occasional

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help us find something far rarer?

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Like gaseous carbon, oxygen or nitrogen?

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Can we determine where to find

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the building blocks of life on other worlds?

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