Re: Improved lunar landing architecture

Cardman <do-not@xxxxxxxxxxx> wrote:

> On Wed, 17 Aug 2005 18:09:12 -0700, Hop David
> <hopspageHATESSPAaMmM@xxxxxxxxxxxxxxxxxxxxx> wrote:
>
> >From
> >http://www.ux1.eiu.edu/~cfjps/1400/atmos_struct.html
> >
> >We see that Earth's atmosphere is .00001 bars at 79.2 kilometers. This
> >is a mesosphere altitude where, as mentioned earlier, meteors and
> >occasional space craft burn up.
>
> Well meteors would have a hard time going through the mesosphere, when
> you can imagine what a little friction and heating can do to a lump of
> dirt and ice. However, spacecraft can go right through the mesosphere
> with very little frictional heating. This does not mean though that
> bits cannot break off, simply due to strain on things that stick out.

Where do you get this stuff, Cardman? You are so wrong on so many
things with such gusto that it's hard to believe you're not doing it on
purpose.

> In the case of the shuttle, then this begins it's large frictional
> slowdown at 25.3 km, which is in the stratosphere. Air pressure here
> will be around 5000 times greater than at 79.2 km. The shuttle's main
> problem is that it is going at 0.76 km/s at this point.

The shuttle starts its period of "peak heating" as it passes down
through 80 km, entering the mesosphere at just barely less than orbital
velocity. By the time it reaches 25 km, it has already shed about
ninety percent of that velocity.
.

Quantcast