[amsat-bb] Re: Since We Are Off Topic Somewhat....

Jim Jerzycke kq6ea at pacbell.net
Thu Feb 14 18:04:02 PST 2008


Because on the way up, as its accelerating, the air is
getting thinner. On the way down it only has the drag
of the atmosphere to slow it, so it caries more of its
velocity into the thicker air.
Jim  KQ6EA

--- Joe <nss at mwt.net> wrote:

> Hi All,,
> 
> Since we are somewhat off topic for the moment with
> the conversation 
> about the bird to come down shortly..
> Ok,  the question is,  and i've asked it to several
> other places, and 
> yet to even get a answer,
> 
> The question is,,,
> 
> Space shuttle launches,,  starts off at sea level, 
> and in less than ten 
> minutes goes from  zero to 17K MPh (or so)  And gets
> to orbital altitude.
> 
> Time to come down,, the de-orbit burn happens to
> slow it down just a bit 
> to cause the orbit to more or less decay.. It's at
> orbital altitude.. 
> and moving at about 17K MPh..  45 minutes or so
> later it's back on the 
> ground and moving at zero MPh..
> 
> So in actuality it comes down from space even slower
> than going up.  
> Yes?  45 min vs 10.
> 
> Ok,  same goes with any satellite,,
> 
> How come,  going up,,  0 to 17K MPh through the
> atmosphere, all  is 
> fine..  BUT
> 
> coming down,,  17K MPh  to 0  unless it has
> protection  it will  burn up 
> in the atmosphere from friction with the air.
> 
> why is it different?
> 
> Joe WB9SBD & NSS
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