After a century, most low-earth orbit (LEO) satellites will have re-entered.
After a thousand years, maybe half of what’s currently up there (including debris) will be de-orbited.
The rest will be scattered here and there, most probably no longer in their original, useful orbits.
The nice thing about LEO is that it is quickly self-cleaning. I am more concerned about putting large numbers of new satellites (many that would, likely, be DOA) into higher orbits, where they are at risk of colliding and creating debris that would render these orbital altitudes unusable for centuries. Space debris is a problem actively being studied today.
(My research group is looking into deployable drag sails…think space umbrellas…to increase atmospheric drag for sats in orbits low enough to benefit from such help at end of their service lives. It may be an easier sell to a satellite provider to just have this little box from which this sail pops out after the satellite’s 10 year life is over, rather than telling them to find a more expensive way to return their space junk to earth.)
It’s perhaps worth mentioning that satellites in low Earth orbit are fairly easily visible to the naked eye, but nothing currently in geosynchronous is (though you could, in principle, put something up there that was large enough, like Pern’s colony ships).
It might also be worth mentioning that there are some geosynchronous satellites which are not geostationary: Their orbital period is one day, but their orbits are inclined, eccentric, or both, causing them to pass over a figure 8 shape on the surface. This is most often done because you want to consistently have line of sight to some point on the surface at high latitude.
The Japanese navigation satellites are in such orbits. There’s only 4 of them and the orbits are spaced out in a lopsided figure-8 pattern. That means that at least one of them is near Japan at all times. By themselves, they aren’t a complete nav system, but rather are supplementary to GPS. It’s needed because in cities, line-of-sight to enough GPS satellites is frequently not available because of tall buildings. Or in mountainous regions because of terrain.
Another example is the first set of satellites for the Sirius satellite radio. Satellite radio receivers do not have directional antennas (dishes), so it was OK for the satellites to move around in the sky, as long as at least one satellite was up in the sky at any time. This specific orbit is called the Tundra orbit.
The newer satellites are in geostationary orbit, I don’t know why they switched, maybe something to do with the merger between Sirius and XM (which used geostationary satellites from the beginning).
Or like programming someone’s GPS to use Gilbert Gottfried’s voice - annoying, but not sentient (all the computer did in Tomorrow is Yesterday (as I recall) was address Kirk as Darling).
Whom do I talk to about obtaining clearance for my orbiting starship, and how much does it cost, say for a desirable geostationary spot, or a polar orbit?
What if someone does not pay? I doubt they shoot the satellite down…
The ITU handles allocation of geostationary orbit slots.
The FCC regulates all radio communications including satellite communications. I believe any company that does business in the US needs to comply with their regulations.
I was hoping this would be a discussion on scientific basis, not fictional ST episodes (even if the OP mentions ST). Its been a rainfall of ST fan masturbation. I dont get ST at all, it seems cheesy to me. But arent there any scientific answers to the OPs question, from non ST sources. It would be interesting…
Almost every answer in this thread is based on science.
But if you think the OP’s question hasn’t been answered scientifically, maybe we interpreted the question differently. So could you please rephrase the question as you interpreted it? I’m sure we can provide a scientific answer to that.
My biggest complaint about ST was that with the most advanced starship in the known galaxy just about every episode ended with Kirk in a fist fight with the bad guy…
The problem is the lower atmosphere. As others have repeated, the atmosphere creates noticeable drag on anything within 200 to 300 km of earth. Note too that many satellites are solar powered, and built as light as possible, and certainly not aerodynamic; so they respond to atmospheric drag easily. Skylab was an empty tin can with sails (or “sail” only one unfolded) it will slow down very easily with that drag. However, with decay times measured in months and years, you can see that the amount drag is not the same level as our surface level experience of wind resistance.
Another interesting orbit I read about was Soviet broadcast satellites serving their north. The orbit was a very elliptical and inclined orbit every 12 hours, using several satellites; their apogee’s were space out evenly. Remember a satellite moves most slowly at apogee. So what a Siberian observer would see is a satellite rise over the horizon, ascend to a spot in the sky overhead (for a high latitude) appear to hang there barely moving for a while, then drop to the horizon. Meanwhile, as it drops, another satellite is rising to perform the same pattern… over and over. (Geosynchronous was not worthwhile because the satellite would be too close to the south horizon)
So what happens in this case? The perigee is low, within the zone where drag is a factor. So the speed at perigee slowly degrades. If you degrade perigee speed, the apogee descends. So after several years, the satellite will start to become more circular in its orbit (and hence less useful). Eventually, the satellite will decay, spiral in, and plunge to earth like a circular-orbit satellite.
I’m going to guess that by themselves, geosynch and higher satellites will last for millennia if not millions of years. If Vanguard I 3rd stage - essentially an empty tin can - is still orbiting 5,000 miles up after 61 years, it’s a safe bet that something at 22,000 miles with far far less atmospheric drag isn’t going anywhere anytime soon. The biggest problem is when these run out of maneuvering fuel and their orbits perturb aimlessly based on tugging from moon and sun. (My totally unscientific guess is that they will end up in some orbit numerically out of lockstep with the moon, or in a band between two harmonic orbits). IIRC there are bands in the asteroids which correspond to fractions of Jupiter’s orbit. Similarly, there is at least one gap in Saturn’s rings due to orbital resonance with Mimas. Maybe geosynchronous satellites will settle into permanent orbits within bands defined by the moon’s shepherding abilities.