You cannot own something that doesn't have a definite existence. You might be able to copyright it though.
As for airspace, I believe there are international laws about how high above a country you have to go to avoid the risk of being shot down - or generally complained about depending on the weaponry available.
Originally posted by KazetNagorra That depends on the legal system of course. But in practise I think it's usually whoever owns the patch of land beneath it, to reasonable limits.
I think the land owner only owns a very small area above the land. Here in cape town you need permission from your neighbors before you build upwards because you might be blocking their line of sight. Also if you go a little higher you enter the airspace used by aircraft etc and I think the government controls that ie you cant tell planes not to fly over you, but the government can tell you not to fly your kite/hot air balloon in their airspace.
Much higher up where the satellites roam its first come first serve.
Originally posted by FabianFnas Does this mean that I own the moon, if it happens to sweep through in exact zenith over my garden, even for a minimal time period?
Originally posted by KazetNagorra Would that be "reasonable"?
Reasonable or not, I cannot do anything with the moon during this short time. Like sell it or so.
So it will be only in my mind that I am the richest person in the world, and in the next instant my neighbour is.
"The President in Washington sends word that he wishes to buy our land. Buy our land! But how can you buy or sell the sky? the land? The idea is strange to us."