WEBVTT FILE

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Today we're going to cook a comet.

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For this recipe you'll need one comet, as large as you can find.

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Make sure it's nicely layered with ice and various other frozen compunds.

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Set it on track to head past our sun, and

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slowly turn the heat up as it apporaches. Cook the outter layer of

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the comet in the sun's radiation. The material on the

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comet's surface will go directly from solid to gas. We call this process

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sublimation. The process of sublimation will help

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transfer the sun's energy away from the comet's crust, keeping it cool.

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Sublimate the water ice into water vapor, this will

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release trapped dust to trail off the comet. Notice how the comet

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forms a tail. Add ultraviolet light to the dust.

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This will help make our comet bright. The more dust our

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comet has, the brighter it will appear. Allow the vapor

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to escape through the comet's crust. These jets may slightly

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jostle it or cause it to rotate. Your comet will not

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cook evenly. The side facing the sun will sublimate faster than the other

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side. Bring the comet closer to the sun and the tail will

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disappear. Materials are sublimating so quickly now, the

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vapors exist just long enough to appear on the surface. The sun's

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gravity will deform the comet into an oblong shape.

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Observe what materials continue to sublimate. This will give you

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clues about the comet's composition, density, and mass.

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Hopefully your comet is strong enough not to fall apart. If it survives

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the sun's gravity and radiation, maybe one day it will visit us again.

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(music)

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(beeping)

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(beeping)

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