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Subject: SPACE Digest V9 #345

SPACE Digest                                      Volume 9 : Issue 345

Today's Topics:
        Re: Success with cold fusion reported
         Re: Solid State Fusion for Launchers
Re: summary of Dr. Stanley Pons seminar of 3/31/89 (long, > 200 lines )
    Re: Soviet Launch Sites (was Re: space news from Jan 16 AW&ST)
               Request for information
          Re: Building a fusion-based rocket
          Space applications of cold fusion
         Re: Solid State Fusion for Launchers
         Re: Solid State Fusion for Launchers
                 Cold fusion
             Add to mailing list
----------------------------------------------------------------------

Date: 30 Mar 89 23:18:40 GMT
From: cs.utexas.edu!ut-emx![e-mail]  (Ethan Tecumseh Vishniac)
Subject: Re: Success with cold fusion reported

In article <[e-mail]>, [e-mail] (John Abt) writes:
>
> With unlimited cheap and pollution-free energy available, we won't be
> talking about the greenhouse effect, it will be the furnace effect.

The greenhouse effect is not due to the release of energy from burning
fossil fuels.  It is due to the accumulation of carbon dioxide (and other
gases) in the atmosphere which affects the retention of solar radiation.
Heating the planet as direct effect of power generation would take
an enormously greater per capita consumption of energy for the whole
planet than the present per capita use in the USA.  In other words,
the use of fusion power as a source of energy is less of a problem
from the point of view of the greenhouse effect than any other
energy generation scheme, with the exception of fission power.
I include solar energy here because solar collectors tend to locally
decrease the albedo of the Earth.

An example of a real problem with cold fusion (as reported in the press,
I make no claims for its reality) would be its tendency to irradiate
its container vessel with neutrons (producing some quantity of
low level radioactive waste) and release tritium (a nasty isotope
of hydrogen with a tendency to get absorbed into body tissues and
a half life short enough to give a healthy dose of radiation per unit
time).  The first may less of an issue with cold fusion than hot if
the claim of a low neutron yield holds up.  The second requires
some care (although the short half life might make waste disposal
a manageable problem).  I have no idea, in practical terms, how
much it will cost to deal with these issues, but if you want to
speculate about problems with cold fusion they make a good starting
point.  Thermonuclear fusion has lots of problems as previously
discussed here and elsewhere.

I note that given sufficiently cheap energy it is possible to overcome
most pollution problems associated with modern industry.
--
 I'm not afraid of dying     Ethan Vishniac, Dept of Astronomy, Univ. of Texas
 I just don't want to be     {charm,ut-sally,ut-emx,noao}!utastro!ethan
 there when it happens.      (arpanet) [e-mail]
    - Woody Allen            (bitnet) [e-mail]

These must be my opinions.  Who else would bother?

------------------------------

Date: 3 Apr 89 12:10:33 GMT
From: jumbo![e-mail]  (Jorge Stolfi)
Subject: Re: Solid State Fusion for Launchers


Most postings to this newsgroup seem to assume that the discovery of
cold fusion is a great boon to the exploration and colonization of
space.  This does not seems obvious to me.  From what I have read
so far, cold fusion may help space exploration only a litle,
and hamper space colonization quite a lot.

Let's assume that cold fusion will indeed turn out to be a source of
cheap energy, and not a mere laboratory curiosity.  Still, it seems a
safe bet that it will take at least 5 to 10 years for cold fusion power
sources to become sufficiently efficient, practical, and reliabe to be
used in space.  Even then, there is no indication that cold fusion will
be of any use as a first-stage propulsion system.  At this point, the
only use for cold fusion in space that seems plausible enough is as a
source of electricity, which could perhaps be used by relatively
low-thrust ion motors.  Note that energy is only a small fraction of
the cost of a launch, so cheap energy on the ground will not make space
launches much cheaper.

On the other hand, cheap energy on the Earth means there won't be any
need for solar power satellites (SPS).  Now, SPSes are the only
large-scale space operation that is not obviously an economical
nonsense.  Without SPSes, space colonies would lose their main raison
d'etre; and without space colonies, there is hardly any reason to
consider lunar and asteroid mining.  (By the way, cheaper energy would
make possible to exploit many low-grade ore bodies that now are
uneconomial, so mining the asteroids for the Earth market would make
even less sense that it does now.)

To summarize, I bet that in the foreseeable future cold fusion may turn
out to be of some use *in* space, but it will not make going *to* space
any easier.  In fact, if it is successful, it will make the
colonization of space a lot harder to sell.

                Jorge Stolfi @ DEC Systems Research Center
                [e-mail], ...!decwrl!stolfi
---------------------------------------------------------------------------
    ``My dear listeners,'' he went on, ``if we are to believe certain
    narrow-minded people --- and what else can we call them? --- humanity
    is confined within a circle of Popilius from which there is no escape,
    condemned to vegetate in this globe, never able to venture into
    interplanetary space! That is not so! We are going to the moon, we
    shall go to the planets, we shall travel to the stars just as today
    we go from Liverpool to New York, easily, rapidly, surely, and the
    oceans of space will be crosed like the seas of the moon!''
        --Verne, _From the Earth to the Moon_ (1865)
---------------------------------------------------------------------------
DISCLAIMER: Opinions are just opinions.

------------------------------

Date: 3 Apr 89 06:51:10 GMT
From: silver![e-mail]  (Lucius Chiaraviglio)
Subject: Re: summary of Dr. Stanley Pons seminar of 3/31/89 (long, > 200 lines )

In article <[e-mail]> [e-mail] (Timothy K Reynolds) writes:
>            No 2.45Mev neutrons were detected.  He speculated that these
>            neutrons may be consumed by reaction with Li:
>
>                        7Li + n + 2.45MeV ---> 3T + 3He + n
>                           6Li + n ---> 3T +3He + 4.5MeV

    Neither of these equations is balanced -- the first contains 3 protons
and 5 neutrons on the left as opposed to 3 protons and 4 neutrons on the
right; the second contains 3 protons and 4 neutrons on the left as opposed to
3 protons and 3 neutrons on the right.  Also, are you sure the second reaction
is supposed to be exothermic?  I think I have seen these before, but I can
only remember the first one with any degree of accuracy:

    (7)Li + n --> (3)H + (4)He + n

where the neutron comes out slower than it went in (thus supplying the energy
for the reaction).  I can't remember whether the second reaction should be

    (6)Li + n --> (3)H + (4)He

or

    (6)Li + n --> (3)H + (3)He + n

with the neutron again coming out slower than it went in.  I saw these
equations (obviously only one version of the second one, but I can't remember
which one) in some report on conventional fusion experiments discussing ways
to breed tritium.  (I think this report was from the Princeton Plasma Fusion
Physics Laboratory, but couldn't swear to that.)

    My other question is:  these people used a cell with palladium and
platinum electrodes and heavy water.  Where would the lithium come from?  I
didn't hear any mention of lithium in the electrodes or in the solution
before this article that I am replying to.

--
|  Lucius Chiaraviglio   |  ARPA:  [e-mail]
BITNET:  [e-mail] (IUBACS hoses From: fields; INCLUDE RET ADDR)
ARPA-gatewayed BITNET:      [e-mail]
Alt ARPA-gatewayed BITNET:  [e-mail]

------------------------------

Date: 3 Apr 89 14:37:55 GMT
From: cfa!cfa250![e-mail]  (Jonathan McDowell)
Subject: Re: Soviet Launch Sites (was Re: space news from Jan 16 AW&ST)

From article <[e-mail]>, by [e-mail] (Glen Overby):
> If I recall correctly what was said in James Oberg's _Red Star in Orbit_,
> the city of Baikonur doesn't even exist!

The main Soviet launch site really is called Kosmodrom Baykonur.  There
is a huge sign saying "Baykonur" at the entrance! It should not be
confused with the village of Baykonur some 200 km uprange.  The
cosmodrome lies several miles from the city of Leninsk, which was built
on the site of the small town of Tyuratam; Western sources still
sometimes refer to the launch site as Tyuratam. The Soyuz pads
at Baykonur are located at 46.0 degrees N, 63.5 to 64.0 degrees E.
The SS-9 pads are at about 63.0 degrees E, and Proton and Energia
are somewhere inbetween. It is a huge place. (Coordinates based
on Landsat photos and on working back the orbital ground tracks.)


 .----------------------------------------------------------------.
 |  Jonathan McDowell       |  phone : [phone]              |
 |  Center for Astrophysics | uucp: husc6!harvard!cfa200!mcdowell |
 |  60 Garden Street        | bitnet : [e-mail]        |
 |  Cambridge  MA 02138     |  inter : [e-mail]   |
 |  USA                     |   span : cfa::mcdowell              |
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 |                          |    FAX : [phone]              |
 '----------------------------------------------------------------'

------------------------------

Date: Mon, 03 Apr 89 16:40:45 CDT
From: "Patrick Tebbe" <[e-mail]>
Subject: Request for information

I'm sending this as a member of a group at the University of
Missouri-Columbia, under the direction fo Dr. Sam Haddad, who is trying
to organize a model rocketry competition which will be presented to the
AIAA(American Institute of Aeronautics and Astronautics), hopefully to
be established as a contest for university and college chapters across
the nation. We are looking for information and suggestions, particularly
on any existing contests.  How are they organized, what are the
requirements, ect.? Also, who could we contact for more information or
support?  It will work best for all if any replies could be sent
directly to me.  Any help is appreciated, thanks for everyones time.
Patrick Tebbe c487031@umcvmb BITNET  University of Missouri-Columbia

------------------------------

Date: 3 April 1989 17:36:47 CST
From: "Tom Kirke 996-4961" <[e-mail]>
To: <[e-mail]>
Subject: Re: Building a fusion-based rocket

oliveb![e-mail]  (Philip Stephens) writes.

>From article <[e-mail]>, by [e-mail]
> (Keith P. Mancus):
>>
>>     1>  This is the fusion reactor.  Presumably it uses liquid D2O
>>         at very high temperature.  Ideally it should run at 650 C
>>         or so, and very high pressure.  It vaporizes the working fluid.
>
>Why boil the D2O?  Better to pressurize it so it remains in contact (very
>high pressure at 650 C, so I'm not sure how hot you can practically run
>if following my suggestion), and use a non-Pd heat sink to transfer the
>heat energy to another working fluid.

At 650C it does not matter what the pressure is.  I do not have the data
for D2O but the critical temperature for H2O is 374C.  Above 374C H2O has
only one phase, a fluid, at ANY pressure.  I agree that higher pressures
give better heat transfer but whether or not to boil is not a question.

Tom Kirke

------------------------------

Date: Mon,  3 Apr 89 15:14 CST
From: Scott Hess <[e-mail]>
Subject: Space applications of cold fusion
Original_To:  BITNET%"[e-mail]"

What with all of the speculation on this new cold-fusion, I was thinking
of its applications to space. Beyond using it for power while in orbit,
and on the ground, I was wondering on ways to use it in launching. I can
think of a bunch of ways: atomic ramjets, launching tracks (accelerate it
up to escape velocity, and let it go), vertical launching tracks (same idea,
but tracks pointing up instead of horizontally - requires alot more
acceleration), one of those solid elevator things from Arthur C. Clarke's
"Fountains of Paridise". One device I've read about in Jerry Pournelle's
"High Justice" used lasers. It seems that a powerful ground-based laser
is fired into a cavity at the bottom of the spacecraft. It is pulsed on
and off, at a high speed. The cavity is vented in such a way that it draws
in air. The laser heats the air very quickly, so the air pushes out the
bottom, propelling the craft. Then more air is brought in ... Basically
a ramjet with half the engine ground-based. I believe that I read elsewhere
that Pournelle is on an advisory commitee to the president, and the original
proposal for SDI called for large ground-based lasers, and orbiting mirrors.
Besides being simpler and easier to maintain, this setup could be used with
the above scheme to launch.

My basic question is this: Does this work? I think that an upward force
can be exerted, but is it enough? This only can work where there is enough
atmosphere, so it would have to be able to aquire a pretty good acceleration.
In the book it seems the acceleration was 10G, for about 30s. I don't know
if that's enough. Also, unmanned pods got something like 30G. This seems
a bit high, to me.

Scott Hess,
<[e-mail]>

------------------------------

Date: 2 Apr 89 17:38:16 GMT
From: iconsys![e-mail]  (Mark Muhlestein)
Subject: Re: Solid State Fusion for Launchers

[ mention is made of use of fusion energy for launch ]

Could someone comment on the use of cheap energy to power some kind
of laser launch system?  I remember reading somewhere about a design
in which argon gas in the launch vehicle was heated by a (very large)
ground-based laser system.

Maybe some of the SDIO research may yet come in handy!


--

    Mark Muhlestein @ Icon International Inc.

uunet!iconsys!mmm

------------------------------

Date: 4 Apr 89 00:00:00 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Solid State Fusion for Launchers

In article <[e-mail]> [e-mail] (Mark Muhlestein) writes:
>Could someone comment on the use of cheap energy to power some kind
>of laser launch system? ...

Energy is not the major bottleneck in laser-launch systems, unless you
want to launch seriously big payloads in one lump.  Beam-directing optics
are probably the biggest challenge.

>Maybe some of the SDIO research may yet come in handy!

The US laser-launcher research program is indeed relying on SDI to build
big lasers and figure out how to point them; they're working on the other
engineering problems of the scheme.
--
Welcome to Mars!  Your         |     Henry Spencer at U of Toronto Zoology
passport and visa, comrade?    | uunet!attcan!utzoo!henry [e-mail]

------------------------------

Date: Mon, 3 Apr 89 11:49:39 PDT
From: Peter Scott <[e-mail]>
Subject: Cold fusion

If this is valid, how might it affect the cost of antimatter production?

Peter Scott ([e-mail])

------------------------------

Date: Mon, 3 Apr 1989 9:53:38 PDT
From: Bill Yeager <[e-mail]>
Subject: Add to mailing list

Would it be possible to send this digest to

[e-mail]

This is NOT a mail distribution list, but rather an alias to a program that
builds a bulletin board. We use it to centralize our disk space for
digests and the like?

Thanks,

Bill Yeager

------------------------------

End of SPACE Digest V9 #345
*******************