Keeping The ISS In Orbit

[Bhodi Li]

So to the best of my knowledge the USS uses thrusters to keep it in orbit which means it must constantly expend fuel to stay in orbit. What Im wondering about is how much of a problem atmospheric drag is when you're up that high. You would never be able to maintain orbital velocity at sea level without thrusters because the atmosphere is way too thick there and it would cause tremendous drag, (also if you tried to put an object into orbital velocity at sea level it would hit something but that's beside the point) but at the altitude of the ISS I believe the atmosphere is very thin.

The ISS is up in the thermosphere which is higher than what an airplane can fly. An airplane needs a certain thickness in the atmosphere in order to properly function and so that's why you can only fly so high in an airplane, when the atmosphere gets too thin the airplane won't fly properly, so the highest a conventional airplane can fly is the stratosphere I believe, in the mesosphere the atmosphere is too thin for the plane to fly. The thermosphere which is even higher than the mesosphere and thinner than the mesosphere, therefore, at that height, how much of a problem is atmospheric drag?

 

[Classical Motion]

When you measure it, it appears faint. But the faintness is always working against you. It's continuously accumulated against your velocity. A drag. Any at all is a drag.

 

[Bhodi Li]

When you measure it, it appears faint. But the faintness is always working against you. It's continuously accumulated against your velocity. A drag. Any at all is a drag.

And yet the moon experiences atmospheric drag because yes the moon is in the Earth's atmosphere even if just barely. The geocorona extends out past the moon's orbit so the moon does experience drag no matter how slight, and as you said any drag is a drag, and the moon doesn't need thrusters to stay in orbit.

 

[Classical Motion]

The drag particles for the moon, probably has the same velocity as the moon.

 

[Rob77]

And yet the moon experiences atmospheric drag because yes the moon is in the Earth's atmosphere even if just barely. The geocorona extends out past the moon's orbit so the moon does experience drag no matter how slight, and as you said any drag is a drag, and the moon doesn't need thrusters to stay in orbit.

Interestingly, the moons orbit is continually increasing so any drag seems negligible due to other forces at work.

 

[Tundatech]

Would it be somehow possible to boost ISS station to lunar altitude? Or possibly to lunar orbit. Maybe equip ISS with additional thrusters for moon landing. Whatever the condition of the station after touchdown. it would become a valuable salvage resource for future base construction. What would be the cost comparison to launching that much material from earth to the moon in the future? Or with a successful soft landing would give us a huge jumpstart for a long term presence in a viable shelter. Overcoming earth gravity is a huge part of every space mission leaving earth. Weight goes hand in hand with the fuel to lift it. Yes the ISS has a lot of mass. We can all agree with that. Most of the lifting has already been done. We just need to push it a little more.

 

[Tundatech]

Extending the ISS for lunar purposes would sit well with the conservation community and may bode well for the endeavor politically. It's kind of outside the box. But it's something I haven't seen any discussion on. We could extend this to the salvage of satellites as well. But as far as what it's going to take to firmly beat China in the race for a lunar presence. It seems to me that some out of the box ideas might be worth consideration.

 

[Rob77]

Extending the ISS for lunar purposes would sit well with the conservation community and may bode well for the endeavor politically. It's kind of outside the box. But it's something I haven't seen any discussion on. We could extend this to the salvage of satellites as well. But as far as what it's going to take to firmly beat China in the race for a lunar presence. It seems to me that some out of the box ideas might be worth consideration.

I'm sure the think tanks at NASA would have explored all possibilities. Basically the ISS is old and leaks like a sieve. Its like buying a used car and keep pouring money into it to keep it running, but the technology is still the same and hard to integrate newer tech into it. Plus replacing parts in space isn't so easy. Eventually it will end up not fit for purpose.

 

[billslugg]

It takes 9256 m/s of delta V to put something into a 250 km LEO. This is where ISS is. Figure another 2440 m/s to geostationary orbit, then 1500 to orbit the Moon and then 1721 to land on the Moon. In order to send ISS to the Moon, we would need to imbue it with 5661 m/s of delta V. This is 61% of the delta V we gave it so far. There would be no interest in doing this.

 

[Bhodi Li]

Would it be somehow possible to boost ISS station to lunar altitude? Or possibly to lunar orbit. Maybe equip ISS with additional thrusters for moon landing. Whatever the condition of the station after touchdown. it would become a valuable salvage resource for future base construction. What would be the cost comparison to launching that much material from earth to the moon in the future? Or with a successful soft landing would give us a huge jumpstart for a long term presence in a viable shelter. Overcoming earth gravity is a huge part of every space mission leaving earth. Weight goes hand in hand with the fuel to lift it. Yes the ISS has a lot of mass. We can all agree with that. Most of the lifting has already been done. We just need to push it a little more.

The problem with raising the ISS to a higher orbital altitude is that it means more exposure to radiation from the sun for those staying on the ISS which can be very harmful especially considering the fact that people spend months there. Also, it would make the ISS much harder to get to from the Earth. It took the Saturn V rocket to get people to the moon so that's what we would need, or something like it, if we put the ISS at the same altitude as the moon.