[MUSIC PLAYING] What does the James Webb Space Telescope have to do with the world's largest centrifuge? We are here at NASA's Goddard Space Flight Center in Greenbelt, Maryland to find out Hi, Bill. 

Hi, Mary. 

I was told you can tell us more about this centrifuge that we're standing on. The only centrifuge I know was in my chemistry lab. 

It's exactly like that except bigger. 

So why does Goddard have such a big centrifuge? 

Well, we use the centrifuge here to generate the same forces that a payload would see when it's launched in a rocket. 

How big is this thing? 

This room is about 150 feet in diameter. And the centrifuge is about 140 feet in diameter. We can spin this arm to about 156 miles an hour. But the wind is actually 200 miles an hour when we're spinning. 

So is it like being in a hurricane or something? 

If you were in the center of the centrifuge and it was spinning, you would see or feel no load. 

So what kind of payloads, if you will, do you test on a centrifuge of this size? 

We test large spacecraft. We've tested small parts of the spacecraft. We've tested SUVs here on this centrifuge. 

Well, thank you so much for introducing us to the world's largest centrifuge. And we're going to talk to somebody else to find out how JWST is using this. So, Eric, you guys are using this centrifuge to test pieces of the James Webb Space Telescope? 

That's right. We have our ISIM structure up here. It's the structure that holds all the science instruments on the James Webb Space Telescope. And we're using the centrifuge kind of like a big merry-go-round. Spin it up really fast and show that the structure can hang on to the telescope just like it'll have to do during launch. We're going to test to 7g's to show that it can hold on to the rocket. 

7g's-- is it like we are seven times heavier than we are? 

That's exactly what it is, seven times the Earth's gravity. And then when it gets to zero g way out in space, we have to show that it's the same shape as it was here on Earth. 

Well, thanks, Eric, for showing us how the James Webb Space Telescope program is using the centrifuge. 

My pleasure. 

Now you can see how a virtual spin around the block will help make sure that James Webb Space Telescope withstands the forces and stresses during launch. Thanks for joining us for another edition of Behind the Web. 

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