“If you took the time to read my post you would see that satellites are almost impossible to hide without a lot of effort.”
Rubbish. Just because you can see some satellites in the sky with the naked eye doesnt mean you cant hide them easily enough if you want to, theres plenty that arent visible. And yes vapour trails can happen but you’re ignoring stealth aircraft at night, small drone aircraft, and a few other options.
Again, you are confusing ‘normal operation’ where you dont care at all if you’re seen with ‘trying to hide’ from less advanced civilisations using available technologies with comparatively little effort. The two are very different things, MIR wasnt exactly intended to be a stealth device.
And its not really 10,000 years - the practical telescope is a pretty modern invention (ie more like 400 years), let alone anything more sophisticated. Until then all we really had was the eyeball, so the practical difference with those time periods is pretty much zero.
Otara