Why do astronauts float in space?

In summary, the reason why astronauts float in space is because they and the spaceship undergo free falling due to gravitational pull by the Earth. This is because the spacecraft has much less mass than a planet, making the force of gravity very weak. Even if the astronauts initially stand on the ground of the spaceship, they will still float if they push off or if there is any air circulation.
  • #1
John Pang
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Another question XP.
I have read several articles about the reason why astronauts float in space. I understand that this is because astronauts and the spaceship undergo free falling due to gravitational pull by the Earth. However, this doesn't explain why astronants float inside the spaceship.
 
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If the astronauts and the spaceship are moving at the same velocity and are being accelerated identically, they should stay in the same position relative to each other, yes? Why would you expect this to change just because the astronaut is inside instead of outside?

Are you, perhaps, thinking that the spaceship somehow shields the astronauts from the gravitational pull of the Earth? It does not.
 
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  • #3
Then if the astronauts initially stand on the ground of the spaceship, will the astronauts float ?
 
  • #4
John Pang said:
Then if the astronauts initially stand on the ground of the spaceship, will the astronauts float ?
Ideally, if he or she is initially standing, just touching the spacecraft floor but exerting no force then the astronaut would stay right there.

Practically, if they push off even a teeny bit or if there is any air circulation they can gently float away.
 
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Thank you very much,
I understand now :D
 
  • #6
Gravity is very weak. It takes the mass of the whole planet to produce the force you feel when standing on the earth. A spacecraft has much less mass than a planet so you can't feel anything attracting you to the spacecraft but there is a very very small force.
 

1. Why do astronauts float in space?

Astronauts float in space because there is no gravity in space. In orbit, the gravitational pull of the Earth is balanced by the centrifugal force of the spacecraft's orbital motion, causing objects and people to float.

2. Does this mean there is no gravity in space?

While there is no gravity in the traditional sense, there is still a small amount of gravity in space. This is why objects and people still have weight in space, but they appear to be weightless because they are constantly falling towards the Earth at the same rate as the spacecraft.

3. How does this affect the human body?

The lack of gravity in space can have various effects on the human body, such as muscle and bone loss due to lack of resistance, changes in blood flow, and changes in vision. Astronauts must undergo rigorous physical training before and during their missions to combat these effects.

4. Can astronauts control their movements in space?

Astronauts can control their movements in space by using their hands and feet to push off of surfaces inside the spacecraft. They can also use special tools and equipment, such as jetpacks, to maneuver in space.

5. Why do astronauts wear suits if they are weightless in space?

Astronauts wear suits in space for several reasons. The suits provide protection from the extreme temperatures and radiation in space. They also supply oxygen for breathing and help maintain a normal air pressure for the astronauts' bodies. Additionally, the suits have built-in communication and safety systems that are necessary for spacewalks and other activities outside of the spacecraft.

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