WEBVTT
Kind: captions
Language: en

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This is launch pad 39, at the Kennedy Space Center!

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This is where all the Apollo missions launched from.

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This is where more than 50 Space Shuttle missions launched from.

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This pad here, this is the flame trench

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where all the, the steam generated

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and the fire generated by those rockets comes out

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uhm

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I

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I am

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just

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uh

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astonished to be standing here

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in this place

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and here is something you might not know

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The difficulty with getting to orbit

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is not just the altitude

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it's mainly the speed

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If you want to go to orbit

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Then you have to go 15 thousand miles an hour

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if you're going up to International Space Station height

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15 thousand miles an hour

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That's what most of that fuel goes on

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If you don't have that speed

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then you're going to go up...

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...and you're going to come straight back down

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If you can't go fast enough to dodge the curvature of the Earth

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Then you're just going to come straight back down.

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The energy budget isn't just on altitude, it's on speed.

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It goes from chemical energy in the rocket

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To kinetic energy as it flies

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and goes across

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And then burns it off as heat and friction

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as it plunges back down into the atmosphere.

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If you're just falling through the atmosphere

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you don't burn up

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but if you're going 15 thousand miles per hour

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plunging into it

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and using it as drag to stop

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then, you get the trouble with burning up on reentry.

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So there you go

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the problem with orbit is not altitude

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but speed.

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And that is something you might not have known.

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[Translating these subtitles? Add your name here!]

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And that's that shot gone.