Eli5: if on space Newtown law says that for every action there is an equal reaction, people moving through the ISS will eventualy make it go out of orbit?



They are moving themselves by pulling on the rods, won’t that make the ISS move very little, but after a ton of movement and a ton of time, won’t it move closer or farther from the orbit and collide with earth or drift through space?

In: Physics

When supply ships dock with the ISS they also use this opportunity to boost the station’s orbit using the docked ship’s thrusters.

While the Earth’s atmosphere is *practically* non-existent at 255 miles up, it’s not *literally* non-existent – there’s a slight atmospheric drag on the station at all times that slowly decays its orbit.

The astronauts do slightly change the station’s momentum when they kick off a surface, but they change it back when they hit another surface and it mostly balances out. The atmospheric drag effect is much more significant than anything the crew could do.

I’m not completely sure, but I believe ISS has small thrusters like the space shuttles do. So that way they can correct those movements.

If not the ISS would be just like the satellites in ordit. Slowly but surely the Earth’s gravitational pull will eventually pull ISS into the upper atmosphere and at some point will cause it to crash into the earth.

Either way the ISS won’t get pushed into outter space, but yes the latter explanation will push it out of orbit whereas the former stays in orbit.

Technically yes, but just as the earth is attracted to your own gravitational pull, it will never be enough to do anything noticeable. The ISS weighs 200 tons. And the ISS is in a low orbit, where there’s still atmosphere, but it’s barely noticeable. The molecules that are still there, though, induce drag and slow down the station, so it has to periodically fire the thrusters of a docked ship to push it back into orbit.

Imagine you pull on those rods to drag yourself to another area of the ISS. What will happen when you get there? You’re not going to continue floating in the same direction forever. Eventually, you hit a wall, and in that collision the same rules apply. The wall pushes you back, stopping you,, but you push the wall in the opposite direction, giving the ISS a very small shove in the opposite direction of the one you gave it when you started. So in the end, the whole thing cancels out.

The movement inside the ISS (if you ignore stuff like spacewalks and ships docking to it to resupply it) all equals out.

If you are in the ISS and push yourself of a wall, that will make you move across the room but also accelerate the entire station into the opposite direction. Of course once you have flown across the room and arrest you movement by hitting the opposite wall you will steal just as much kinetic energy from it as your jump of originally imparted.

It is a closed system as long as nobody opens a door. Any effect from any movement you make is counteracted by whatever eventually stops you.

The only way to permanently add anything would be if you throw something out an airlock away from the station.

The station is mostly affected by friction with the uppermost remnants of earths atmosphere slowing it down and it needs to be periodically boosted up into a higher orbit to counteract that.

Any other minor effects pale in comparison to that.