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[Entwood]

Lizzie  ... they are NOT stationary ...  they are geo-stationary ... stationary RELATIVE to the earths surface ... actually moving at quite a high speed given their height above the surface. There is virtually no "drag" so once accelerated to speed they hold that speed for a very long time ... and it needs to be high to overcome gravity which is trying to pull each satellite back down .... so....

centrifugal force (the force created by the movement of the satellite "trying" to go in a straight line - Newtons laws of motion)) is [hopefully] equal to the centripetal force generated by gravity trying to pull it down ...... so it stays up and in one place ... a very difficult balancing act ... it is easier to keep the satellite moving in an orbit which is why navigation satellites, for example, move all the time.

Geo-stationary satellites usually have a small amount of fuel in reserve to keep repositioning themselves ... when they run out of fuel and slow down too much they are doomed to eventualy reenter and burn up...... just takes a long while to happen ..

HTH

[Lizzie_Zoom]

Lizzie  ... they are NOT stationary ...  they are geo-stationary ... stationary RELATIVE to the earths surface ... actually moving at quite a high speed given their height above the surface. There is virtually no "drag" so once accelerated to speed they hold that speed for a very long time ... and it needs to be high to overcome gravity which is trying to pull each satellite back down .... so....

centrifugal force (the force created by the movement of the satellite "trying" to go in a straight line - Newtons laws of motion)) is [hopefully] equal to the centripetal force generated by gravity trying to pull it down ...... so it stays up and in one place ... a very difficult balancing act ... it is easier to keep the satellite moving in an orbit which is why navigation satellites, for example, move all the time.

Geo-stationary satellites usually have a small amount of fuel in reserve to keep repositioning themselves ... when they run out of fuel and slow down to much they are doomed to eventualy reenter and burn up...... just takes along while to happen ..

HTH

Thanks for that Entwood!   I now understand

[Field Marshal Dr. Opti]

Shouldn't that be "any point on the earth's surface on the equator is moving at 1037.5545mph"?

correctomundo a point at the planetary pole is rotating without any relative movement .. it could be considered stationary ..... but it is moving ....  depending on your point of view .. 

It's still rotating around the sun at quite a few leptons, though. .. and is the solar system still, or blatting through the universe? My head hurts.

Best figure I can come up with is about 68,000 MPH. The Earth clearly has a formidable "power to weight" ratio. 

[Nick W]

Going back to the original post, although it might be the shortest day a combination of dopey customers, idiot controllers and crap jobs is making it feel like the longest!