Re: Broken Satellite Will Be Shot Down

On Fri, 15 Feb 2008 07:23:31 -0800 (PST),
hot-ham-and-cheese@xxxxxxxxxxx wrote:

On Feb 15, 1:24 am, Bob Brock <bbr...@xxxxxxxxxxxxxx> wrote:
On Thu, 14 Feb 2008 22:51:19 -0600, "David J. Hughes"





<davidjhughes...@xxxxxxxxxxx> wrote:
Bob Brock wrote:
On Thu, 14 Feb 2008 23:27:42 GMT, Myal <Duma...@xxxxxxxxxxx> wrote:

The Rifleman wrote:

Knowing the US, the missile will probably hit an air liner full of innocent
pilgrims

actually no

the chinese took out a satelite a whileago just showing off that they
got capabilities the yanks dont have

the yanks have been looking for an excuse to prove their manhood in that
respect for a while

the guys on the space station are in BIG danger tho ... friendly fire ya
know ...

My take on it is more along the lines of collateral damage.  Yes, some
of the shrapnel will return to earth.  However, no one knows what
kinds of orbits the shrapnel that goes into alternate orbits will
take.

The precise orbits, no.
The range of possible orbits, yes.
Orbital mechanics can be tricky to discuss in words, but I'll try.

First, they won't be trying to hit it until it is nearing reentry, and
already being slowed by atmospheric drag.  That makes everything easier.
So we have a base orbital velocity of @ 7.8 Km/sec. (80 Km from sea
level, 90 minute orbit)
It gets hit, breaks up into lots of pieces with various vectors
(combination of direction and velocity).
Any piece that is knocked down (towards earth) with a slower velocity
than 7.8 km/sec, hits the atmosphere and burns up.
Any piece that is knocked down with a higher velocity, hits atmosphere
and is slowed, trades velocity for height as it tries to move to a
higher  orbit, ends up about where it was, and falls to earth in a few
day, burning up.
Any piece that is knocked back, has a slower velocity, and falls down
into the atmosphere and burns up.
Any piece that knocked forwards, has a higher velocity, falls out into a
higher orbit, losing velocity as it rises (trading speed for height).

That seems that it might be bad, but we need to do the math.
Assume a maximum total velocity change for any one piece of
300 m/s (671 MPH).  That's probably too high, but it makes the dicussion
easy.
Falling out, it slows due to the force of gravity. It reaches it's new,
higher, slower orbit in @ 40 seconds, and is 8 Km higher.  It will still
be affected by atmospheric drag, and will fall to earth in a few weeks.

Any piece that is knocked straight out, or out and backwards, behaves
about the same as one knocked forwards. Outward vector is lost to
gravity, any excess forward velocity for the new orbit is small, also
lost to gravity, might make to 10 Km higher orbit. Maybe another few
weeks before it burns up.

So, in all cases, the pieces burn up in a couple months, with hopefully
no pieces left big enough to reach the ground, and no pieces move into
orbits that will threaten other satellites.

All this is based on the pieces going into roughly circular orbits.
Any piece that goes into a significantly elliptical orbit enters
atmosphere at its next low point, and burns up, within @60 minutes of
the hit.

OK, you seem to have a pretty good handle on it.  

IOW, you were wrong.

I've been wrong before. There is nothing evil about admitting to
being wrong. You should try it at least once in your life. It would
help your lack of credibility.


Tell me if you can
why the 1000 pounds of rocket fuel would not burn up during re-entry?

If the package makes it through reentry, why would the fuel burn off?

Because it reached it's ignition point? One would think that rocket
fuel would have a pretty low one. Did you see what happened to the
fuel on Challenger during a controlled re-entry?


It surviving until impact is the reason for trying to blow it up
before impact.  Is the rocket fuel not flammable enough to ignite?  

Do you want it to ignite in Chicago, Phoenix?

No.


Is
there something they are not saying?

You mean like a conspiracy?


No. Do you think that every time the government tries to keep
something secret, it's a conspiracy?

I seem to remember that we simply allowed Skylab alone when it
re-entered.  Why is this so different?

That was the 70's. Did we have the capability in the 70's? More
conspiracy?

If you insist.
.

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