On Sep 23, 5:47*am, Anthony Frost wrote:
In message tatelephone
* * * * * Pat Flannery wrote:

* On 9/22/2011 9:08 PM, Andre Lieven wrote:
* On Vanguard One, I found this site:
*
* http://home5.swipnet.se/~w-52936/index20.htm
*
* It's got an ongoing odometer for Vanguard One,
* which, as I type this, has done some
* 11,469,717,200 KM in space...
*
* I notice the orbital lifetime has dropped a bit from what it was in the
* books I had as a kid, where it was supposed to be 12,000 to 20,000 years.
* Has anyone actually figured out what the orbital lifetime of a satellite
* in GEO is before air drag brings it down?

Tidal and gravitational effects from the lumps and bumps on the Earth
dominate at that altitude. Anything below geostationary slowly gets
energy sucked out and spirals down, anything above gets energy pumped in
and will drift further out which is one of the reasons the graveyard
orbit for old satellites is higher than geostationary.

It's the same effect that is making the Moon get further away and will
drastically lower property prices along the Mrtian equator when Phobos
eventually drops in.

* * * * *Anthony

so if the ISS at end of operational life were moved a bit over
geostationary it would slowly drift even higher over time?

that would allow it to be a excellent in orbit museum some day