[extropy-chat] Impact Effects (was: Pluto New Horizons launch -getting ready)

[Amara Graps]

Russell and Spike:
>...A relativistic projectile would certainly turn into plasma as soon as it
>hit atmosphere; I'm guessing there wouldn't be time for the plasma to
>disperse much, though, and would stay in a reasonably concentrated beam,
>making a single crater...

>Ja I don't know how to calculate that.  It would only be in the atmosphere
>for about a millisecond.  perhaps it would form a shock wave of such
>intensity that elements would be fused to iron on the leading edge.  This is
>so far out on the scales that engineers are accustomed to working, we may
>not be able to trust our usual models.

This is what the meteorite community do all of the  time though. For
example: http://www.issi.unibe.ch/teams/Meteo/ If you make an ADS
search on some of those people on that ISSI team, then you will find
many papers.

Also, I gave you folks a pointer to an excellent tool
http://www.lpl.arizona.edu/impacteffects/

I suggest to read through the document to know their assumptions and
equations. I see comments and questions here that tells me that no one
read it. A discussion of the pressures, shock wave, vaporization and
plasma produced (in the instance of fireballs) is discussed in that
paper.

(http://www.lpl.arizona.edu/~marcus/CollinsEtAl2005.pdf)


Robert, I don't know about the MER, but the DAWN mission uses Flash
memory (not that it will do anyone any good if the spacecraft hull
sits on the ground and the instruments remain in long-term storage.)

Amara

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Amara Graps, PhD          email: amara at amara.com
Computational Physics     vita:  ftp://ftp.amara.com/pub/resume.txt
Multiplex Answers         URL:   http://www.amara.com/
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