about a 100 basket-ball sized satelittes fall every year.
Satellites may fall out of the sky because they get too close to Earth. In that case, Earth overwhelmed the power of the satellite's propelling system and slowly but surely dragged the satellite into the Earth's atmosphere.
about 3,000
I think its about 50..
You need 4 to locate a position. There are 24 satellites in use in the sky with 8 spares.
Things That Fall from the Sky has 224 pages.
best to get intouch with military or nasa to find out
Interestingly enough the sattelites are doing their level best at falling from the sky. The whole idea is that at orbital velocity the objects move forward fast enough that they continously miss the Earth as they fall down. In the ideal case satellites are in orbit. This means that they circle the Earth at a specific speed and a specific height. Because satellites aren't in Earth's atmosphere nothing slows them down. If they did slow down it would reduce the height they orbit at. If the height were reduced they would encounter thicker air which would slow them down more, which would lower their height more. This cycle would continue until they crashed. In actuality the satellites do slow down very slowly because the air is not totally absent. Eventually all satellites will fall from the sky.
No they don't move fast in the sky
the sky never did fall and it never will the sky can not fall. it is impossible! they sky is made up of gasses. gass can not fall. so do not worry about the sky falling. it is just a myth.
Satellites orbit the earth for a few years then fall to earth however they are directed to fall to the sea
No, the sky will never fall apart.
No things can fall from the sky though.