On Thu, 24 Jun 2004 04:50:24 GMT, (David
Munday) wrote:

The higher you go the more potential energy you've got to get rid of
in re-entry. As you move from sub-orbital through low earth orbit
(Shuttle) to high earth orbit to lunar return and beyond you end up
with more and more energy to get rid of. I believe it's significantly
worse than just the additional potential energy because of increasing
orbital velocity. I defer to our resident orbit wonk on the point...

Hmmfff. Weren't referring to me, I hope. :-)

I ain't really an orbit type, though I've picked up a bit over the years.

Anyway, you do have it backwards...orbital velocity decreases with circular
orbit altitude. ~25,200 FPS at 200 nm, ~10,100 FPS at geosynchronous
altitude (~19320 NM).

You're right about the potential energy, though. Dropping from
geosynchronous altitude to ground level, you'll hit the atmosphere at over
23,000 miles per hour. And if you're an old-timer like BOb, you'll have
the turn-signal flashing the entire way....

Ron Wanttaja