the Space Station is past the Karmen line, but is it still within " Earth's atmosphere "?
- 1 month ago
Earth's atmosphere gets thinner and thinner as your altitude increases; but even where the Space Station orbits, there's still a trace amount that exists - and, it creates drag.
Skylab was last visited in 1974, and it was thought that it would remain in orbit until the Space Shuttle was ready to 're-boost' it; however, and active period in our Sun caused Earth's atmosphere to expand a bit, and the added drag made it's orbit decay, and it fell out of orbit in July, 1979....
The same thing would happen to the ISS if it wasn't re-boosted every so often. The Shuttle used to use it's fuel and engines to perform a boost when it visited; sometimes they'll used an attached re-supply vessel to do the job, and the ISS has a module with thrusters that can also perform the 're-boost.'
- NyxLv 71 month ago
Those solar panels on the station are huge sails, even with the dozen or so molecules per cubic centimeter the station fly in.
- Anonymous1 month ago
The Kármán line is an arbitrary (made up) boundary of 100 km, about where physicist Theodore von Kármán calculated (83.6 km) that the atmosphere is too thin for winged flight so craft have to be going at orbital velocity to stay aloft. Above that line there are still plenty of air molecules, enough to cause drag on the ISS making it necessary to boost the orbit once in a while.