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

i8cvs domenico.i8cvs at tin.it
Thu Feb 14 17:01:10 PST 2008

----- Original Message -----
From: "Joe" <nss at mwt.net>
To: "'AMSAT-BB'" <amsat-bb at amsat.org>
Sent: Friday, February 15, 2008 12:55 AM
Subject: [amsat-bb] Since We Are Off Topic Somewhat....

> 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

Hi Joe, WB9SBD & NSS

Going up the maximum speed to enter in orbit is reached when the Space
Shuttle is well above the atmosphere in the vacuum and absence of the

Coming down the maximum speed is reached when the Space Shuttle is
well into the atmosphere in friction with the oxigen.

73" de

i8CVS Domenico

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