Btw, a missile or a rocket would probably be more effective than a satellite in your scenario, but hopefully they could get some kind of laser system or the like up and running, that would take a lot of "a"s out of "waaaaaaaay too late".
You can't launch a missile or rocket without a satellite in space...
...which begs the question, how did the first satellite end up in space?
You do know the moon is a satellite... right? I don't see what we're getting at...
I was just curious about why you can't launch a rocket or missile without a satellite in space, although I can see how having the moon could be helpful in that regard in case it's dark at night.
You can launch a missile/rocket into space without a satellite, you just can't aim it.
In answer to the OP, there are lots of ways we could screw civilization up pretty badly over the next 1000 years, but the entire species being extinct/gone is pretty unlikely, and would probably take something out of our control to accomplish, like an ELE or attack by a more advanced species.
But the most likely scenario is enslavement by our own creations. Let me just refer you to some selected pieces from my Matrix fanfiction... *pulls out six inch stack of notebooks*