Why Are Astronauts Weightless?

http://www.abc.net.au/catalyst/team/d...
I have been working with Catalyst on ABC1 to bring some Veritasium to Australian TV. In this segment I ask why astronauts in the space station are weightless. The most common answer is because there is no gravity in space. But of course there is gravity in space, especially where the space station is located (only about 400km from Earth's surface). So astronauts still experience a gravitational pull - it's just that they and the space station are in free fall so they are accelerating together towards the Earth. The space station doesn't crash into the Earth because of its orbital velocity - it's going 28,000 km/h so as it falls, the Earth curves away from it.

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  Education

[Trampokool Mdr]

dude you should have been my science teacher during primary schooling........i wouldn't have done graduation in management

[Gasgaz Gazel]

thank you. that helped

[seth bourgeois]

My science teacher said there was no gravity in space, I told her she was wrong, but.....

She didn't believe me.

[Michealkinane]

shuttles which supply the ISS also sometimes use a booster to increase the horizontal velocity of the station, keeping it in orbit. Also you assumed I did not understand even though you did not know why I thought he was wrong and as you can see I understand all of this very well.

[Michealkinane]

No I do understand. The space station continues circling the earth as it has horizontal velocity which is not decelerating as there is no air resistance in space. See I do understand. I have also taken back my statement about scishow as he said the ISS is in the upper atmosphere implying there are (even if it is just a small amount) air particles up there. I the hypothesized that the ISS would eventually return to Earth as the velocity would be lost, but a kind youtuber told me that the...

[toni R]

nope. you just do not understand.

[Michealkinane]

Scishow was wrong then.

[proto35]

the new bill nye the science guy

[Zhab80]

Actually, it would incinerate like meteor. You can't take that kind of hardcore friction without some extra good thermo shields.

A space shuttle with a tiny little defect in it's thermo shield got incinerated as it was attempting atmosphere re-entry. As do satellites that lose their orbit.

[Kevin Peng]

Because a sphere can enclose the most volume with the least surface area and the surface tension would want to make the surface area as small as possible.

[psicorfo]

The worry isn't the pull, as he said, the station is very close to the earth anyway so it experiences similar gravity to us. If it went much lower than 200km though, the atmosphere would get thicker and the station would start to slow down due to drag so it wouldn't have enough velocity to keep orbiting and it would hit the earth.

[WorldofKrick]

sorry didnt watch video before i commented -.-