Date: Sun, 27 Jul 1997 04:49:47 +0000 (GMT)
From: aufsj@IMAP2.ASU.EDU
Subject: Re: ??? Plasma mirror propulsion...
To: sci-physics-plasma@uunet.uu.net
Organization: Arizona State University
Newsgroups: sci.physics.plasma,sci.physics

: > Is there some big fundamental flaw I'm missing? Has this idea
: > been fleshed out before?

: Only one thing I can think of, besides the megawatt power level to keep
: a killometer sized gas a plasma in free space at 3K, and the cup of
: water a minute that leaks out of the confinement and has to be replaced,
: and thats the terrawatt laser that has to be built to provide this
: source of illumination. Perhaps you could coax a nearby star into lasing
: in the direction we want.

Hmmmm. I'm not certain I follow this (not surprising, it's been a
while since my last physics class :-)).
Is the "kilometer sized" based on a calculation or rhetorical?
Offhand I wasn't thinking anything nearly so large would be needed for a
small test/science payload.
And I'm not certain what you mean by "free space", either. I was
thinking along the lines of a low pressure gas contained by a physical
structure, glass or plastic etc. A few amps is reportedly enough to
create a 10**12 electron per centimeter figure that allows for a plasma
frequency (earlier I mistakenly used "critical frequency") in the
vicinity of 10 gigahertz. Once again, it may be possible to derive solar
power from the direction of travel. The test data I last looked into used
a gas pressure of 150 mTorr and a mag field of 150 gauss. This wasn't
for a propulsion unit, to be certain, but the numbers don't sound all
that outrageous to me (based on my limited knowledge of this field).
Additionally, while light is one good source, one could
presumable use different velocities to utilize (with the proper shift
proportions) whatever frequencies of energy are available, RF, IR or visible
or UV or whatever. The universe appears to be full of sources of these
:-).

regards,

-----------------------------------------------------------------------
"A physicist is a mathematician who has memorized a lot of formulas"
Anon.

Steven J Forsberg at aufsj@imap2.asu.edu Wizard 87-01