In Freefall orbiting Jupiter versus Earth

In summary, an astronaut in freefall on Jupiter would not feel their own weight due to the significant gravitational force acting on them. This is because the force is the same on each particle, resulting in no additional internal stress or strain. The only time they would feel anything is if there was a large differential in gravitational force, which is called tidal gravity. However, this would be negligible for a planet the size of Jupiter.
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Albertgauss
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Jupiter g ~ 25 Would you feel it?
I know that in Earth, an astronaut feels weightless in orbit but actually is not. The astronaut would not feel his own weight until he actually stands on a floor where his feet point towards the Earth as the Normal Force is the perception of weight.

So, in Jupiter, where g ~ 25, an astronaut in freefall also would not feel their own weight. However, does that mean there would be no biological effects despite the increased gravity?

I have heard it said that a person who normally has a weight of 600 Newtons on Earth would then weigh ~ 1500 Newtons on Jupiter, enough to have a heart attack since a normal heart could not pump blood through such excess weight. But if the person is in freefall in Jupiter, this would not happen as they would need to have their feet on the surface of a ship to feel this 1500 Newton. Is this correct?

Please ignore everything else about Jupiter except for what is the discussion here. I am well aware of all the problems of falling into Jupiter, just had a question of this one detail.
 
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  • #2
Let's stick to the classical theory of gravity. There is a significant gravitational force acting when you are in freefall. But, because the force is the same on each particle, there is no additional internal stress or strain that would enable you to measure the overall gravitational force. For that reason, you would feel nothing, whether it's Jupiter or the Earth.

The only time you would feel anything is if the differential in gravitational force between, say, your head and feet was large. This will be negligible for a planet even the size of Jupiter. This is called tidal gravity, and it's this difference in the Moon's gravity between one part of an ocean and another that causes the tides. If, say, the Earth was falling towards Jupiter, then this tidal gravity between the part of the Earth that was closest to Jupiter and the part that was furthest away would be significant and the Earth would be stretched as a result.
 
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Sounds good. I see where I was getting confused. Consider this answered.
 
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FAQ: In Freefall orbiting Jupiter versus Earth

1. How does the force of gravity differ between freefall orbits around Jupiter and Earth?

The force of gravity is directly proportional to the mass of the planet and inversely proportional to the square of the distance between the two objects. Since Jupiter is much more massive than Earth, the force of gravity is stronger in a freefall orbit around Jupiter compared to Earth.

2. Is the speed of an object in freefall orbit around Jupiter the same as on Earth?

No, the speed of an object in freefall orbit around Jupiter is much faster than on Earth. This is because the gravitational force is stronger, causing the object to accelerate at a faster rate.

3. How does the distance between the object and the planet affect the freefall orbit?

The distance between the object and the planet determines the strength of the gravitational force. A closer distance will result in a stronger force and a faster orbit, while a farther distance will result in a weaker force and a slower orbit.

4. Can objects in freefall orbit around Jupiter experience changes in their orbit?

Yes, objects in freefall orbit around Jupiter can experience changes in their orbit due to the influence of other objects, such as moons or other planets. These changes can alter the speed and path of the orbit.

5. How does the atmosphere of a planet affect freefall orbits?

The atmosphere of a planet can create drag and resistance for objects in freefall orbit, causing them to slow down and potentially change their orbit. This is more significant on Earth, as Jupiter's atmosphere is much thinner and has less impact on objects in orbit.

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