Brian Cox visits the world's biggest vacuum | Human Universe - BBC

This is NASA's space power facility near Cleveland, Ohio, and is the largest

vacuum

chamber in the

world

. It is used to test spacecraft in outer space conditions and it does this by pumping 30 tons of air into this chamber until there are approximately 2 grams left. This one I have an eccentric construction. Which is part of this story: it was built in the 1960s as a nuclear test facility to test nuclear propulsion systems and that meant they built it from our material to make radiation easier to handle. Aluminum is not the best, strongest material to build a

vacuum

chamber, so they built a concrete skin that is part radiation shield and part external pressure vessel so this thing can take the force. which is present on the outside when pumped to outer space conditions.

Galileo's experiment was simple. He took a heavy one and a light one and let them fall at the same time to see which fell faster. Now in this case the feathers fell to the ground at a slower rate than the bowling ball due to air resistance. So to see the true nature of Gravity we have to get the air out. It takes three hours to pump the 800,000 cubic feet of air from the chamber. We lower the millet or in the last 30 minutes, but once it is complete. There is an almost perfect vacuum inside the 6104 manual station at 10 percent.

An option for the PCB 30-1 pressure set point at 240 PSI. We're going to launch and nine eight seven six five four cameras in two one launch Yes, look at that. They went down exactly like that Exactly, they won't exactly shut up just a few feathers. Don't move anything, look at that. That's just great. Isaac Newton would say that the ball and the pen fall because there is a force that pushes them down, gravity. That Einstein imagined the scene very differently? The happiest thought of his life was this: the reason the bowling ball feathers fall together is because they are not... ... falling.

They are still. There is no force acting on them. He reasoned that if you could he didn't see rear gravity. There would be no way to know that the ball and feathers were being accelerated toward Earth. Then he concluded: No.