Article: <[email protected]>
From: [email protected](Nancy )
Subject: Re: TUNGUSKA
Date: 1 Mar 1997 20:19:27 GMT
In article <[email protected]> James
Head writes:
>> I don't see aerodynamic stress as being anything that
would
>> cause a large meteor to explode, and with a terrific
force.
>> It slows the meteor down and the friction heats up its
forward
>> side, without having time to penetrate inward at all
far. True,
>> the aerodynamic pressure is greatest near the center of
the
>> meteor's leading side, tapering off away from the
stagnation
>> point, but that constitutes a relatively gradually
applied force
>> whose gradient that tends to deform the meteor and break
it
>> apart, if it is small enough and loosely enough bound,
but does
>> not cause it to explode from inside out.
>>
>> Could your hypothesis be tested in the lab, to see under
what
>> conditions a spherical pellet propelled towards a target
would
>> suddenly explode with great force before reaching the
target?
>> Jim Deardorff <[email protected]>
>
> Suffice it to say that the dynamic pressure (rho*v^2) on an
> entering asteroid is very large, in excess of the crushing
strength
> of rock (a few kilobars). ... As for lab tests, the top
speeds
> achieved in two-stage gas gun experiments is 4-5 km/sec.
> Meteors hit the earth's atmosphere at a speed of at least
twice
> that, more typically several times faster. We cannot
directly
> simulate meteors in the lab.
> [email protected] (James Head)
(Begin ZetaTalk[TM])
Here we have wild assed theory presented as FACT again! You've
OBSERVED meteors entering the atmosphere of Venus, have you?
You've OBSERVED large meteors entering the Earth's atmosphere?
What you have is the speed that shooting stars exhibit when they
set fire and burn so as to become visible to you.
What do your SHUTTLES experience! They arrive on the ground
going as fast as they did when dropping through the upper stratas
of the atmosphere? Can't LPL put more than one fact together in a
string, and contemplate them all at once! Is this a genetic
failing of astronomers who work at it for a living, or do you
take classes to learn how to micro-focus and exclude any data
that interferes with a pet theory?
(End ZetaTalk[TM])