someone tell me that iss is moving or not ?
Answers
Answered by
0
which one is moving or not?????
shivam1234434:
international space station?
sure
ok thx
Answered by
0
hiiii mate
How fast is the International Space Station moving and why? How can astronauts walk/move in the space station when it is moving so fast? How difficult does the dynamic of this fast movement make it for other spacecrafts to dock with the ISS?
This question previously had details. They are now in a comment.
Answer
30
Follow
Request
More
6 ANSWERS

Jack Thompson, Rocket Scientist
Answered Mar 10, 2013
The ISS isn't an aircraft, it's a spacecraft! I want to say it's outside the atmosphere, so there's no air, and no aerodynamic drag - and while that's practically true for the purposes of this answer, it's not correct. It turns out that the thermosphere extends out more than twice as far as the ISS orbits, and so there is a tiny, tiny amount of residual atmosphere which causes a small amount of drag on the ISS. However, the density is so many orders of magnitude less than it is near the surface that it's almost misleading to call it "atmosphere".
The ISS actually has to move that fast to orbit the Earth at its operational altitude. If it were in a higher orbit, it would have to travel more slowly relative to the ground. If it were in a lower orbit, it would have to travel faster, and eventually it would start to pick up substantial drag from the top of the atmosphere, which would mean you'd have to constantly boost to a higher orbit, which sort of defeats the purpose.
The main reason aircraft don't fly that fast in the atmosphere is that it takes an enormous amount of energy to push the air out of the way when you're going very fast. And when you're putting all that energy into pushing air out of the way, that energy has to go somewhere, and most of it goes into making the leading edges of your aircraft very, very hot. This is why the Space Shuttle had those black tiles all over the nose and bottom - the tiles insulated the metal airframe (which would otherwise have melted) against the extreme heat of re-entry.
Imagine you're in a 747 flying through the air at 900 mph. Everything inside the 747 is moving at 900 mph, but relative to what? Relative to the ground beneath you. So for you sitting in your seat, nothing inside the cabin appears to be moving, except for the flight attendant who is bringing you a bag of peanuts.
It's the same on the ISS. To them, everything inside the ISS appears to be stationary, so if they could somehow ignore the lack of gravity, they would hardly notice they're flying at 17000 mph relative to the ground beneath them - unless they looked out the window.
Because it's outside the atmosphere, docking is both harder and easier. Chasing down a vehicle at 17000 mph sounds hard until you realize you have to be going at almost the exact same speed, in the exact same direction, in order to dock - so by the time you get there, your spacecraft and the ISS are barely moving relative to each other, and of course once you dock you aren't moving at all. The hardest part (depending on who you ask!) is reaching a high enough orbit. After that, unless you're in a hurry, you can take the whole docking process pretty slow.
How fast is the International Space Station moving and why? How can astronauts walk/move in the space station when it is moving so fast? How difficult does the dynamic of this fast movement make it for other spacecrafts to dock with the ISS?
This question previously had details. They are now in a comment.
Answer
30
Follow
Request
More
6 ANSWERS

Jack Thompson, Rocket Scientist
Answered Mar 10, 2013
The ISS isn't an aircraft, it's a spacecraft! I want to say it's outside the atmosphere, so there's no air, and no aerodynamic drag - and while that's practically true for the purposes of this answer, it's not correct. It turns out that the thermosphere extends out more than twice as far as the ISS orbits, and so there is a tiny, tiny amount of residual atmosphere which causes a small amount of drag on the ISS. However, the density is so many orders of magnitude less than it is near the surface that it's almost misleading to call it "atmosphere".
The ISS actually has to move that fast to orbit the Earth at its operational altitude. If it were in a higher orbit, it would have to travel more slowly relative to the ground. If it were in a lower orbit, it would have to travel faster, and eventually it would start to pick up substantial drag from the top of the atmosphere, which would mean you'd have to constantly boost to a higher orbit, which sort of defeats the purpose.
The main reason aircraft don't fly that fast in the atmosphere is that it takes an enormous amount of energy to push the air out of the way when you're going very fast. And when you're putting all that energy into pushing air out of the way, that energy has to go somewhere, and most of it goes into making the leading edges of your aircraft very, very hot. This is why the Space Shuttle had those black tiles all over the nose and bottom - the tiles insulated the metal airframe (which would otherwise have melted) against the extreme heat of re-entry.
Imagine you're in a 747 flying through the air at 900 mph. Everything inside the 747 is moving at 900 mph, but relative to what? Relative to the ground beneath you. So for you sitting in your seat, nothing inside the cabin appears to be moving, except for the flight attendant who is bringing you a bag of peanuts.
It's the same on the ISS. To them, everything inside the ISS appears to be stationary, so if they could somehow ignore the lack of gravity, they would hardly notice they're flying at 17000 mph relative to the ground beneath them - unless they looked out the window.
Because it's outside the atmosphere, docking is both harder and easier. Chasing down a vehicle at 17000 mph sounds hard until you realize you have to be going at almost the exact same speed, in the exact same direction, in order to dock - so by the time you get there, your spacecraft and the ISS are barely moving relative to each other, and of course once you dock you aren't moving at all. The hardest part (depending on who you ask!) is reaching a high enough orbit. After that, unless you're in a hurry, you can take the whole docking process pretty slow.
Similar questions