Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V15_5/V15NO587.TXT

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Date: Wed, 23 Dec 92 05:12:19
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #587
To: Space Digest Readers
Precedence: bulk


Space Digest                Wed, 23 Dec 92       Volume 15 : Issue 587

Today's Topics:
                              Accounting
                       asteroids beyond Jupiter
                 Aurora chase planes (was Re: Aurora)
                               Breeders
                      DC vs Shuttle capabilities
                          ground vs. flight
             Justification for the Space Program (3 msgs)
                        LEI financing (2 msgs)
Lunar Resource Mapper Status (Was Re: funding for Lunar Prospector) (2 msgs)
                           MOL (and Almaz)
   People who can't count costs (Was Re: Terminal Velocity of DCX?)
                      SSTO vs. 2 Stage (2 msgs)
           Terminal Velocity of DCX? (was Re: Shuttle ...)

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

Date: Tue, 22 Dec 92 22:54:48 EST
From: John Roberts <[e-mail]>
Subject: Accounting

-From: [e-mail] (Allen W. Sherzer)
-Subject: Re: Terminal Velocity of DCX? (was Re: Shuttle ...)
-Date: 22 Dec 92 16:07:15 GMT

-In article <[e-mail]> [e-mail] (Brian Stuart Thorn) writes:
-> The Space Transportation budget this year was about $5 billion, if
-> memory serves. NASA flew 8 Shuttle missions this year.

-This number does not include NASA overhead, amortization of the orbiter,
-amortization of Shuttle development costs, and a host of other costs. Adding
-those in puts the cost at well over a billion per flight. Hell, interest
-costs on development alone adds over a quarter billion per flight (BTW,
-this interest is not a sunk cost since it is part of the national debt and
-we are paying for it even now).

Accounting is a very complex field - I'm not convinced that there's any
obvious "right" way to do accounting. But in any event, amortization of
past development costs is not a legitimate argument for scrapping an existing
system. In fact, I expect that if you want to consider getting rid of an
existing system and developing a new system to replace it, you should compare
the *operational* costs of the existing system to the *operational plus
development* costs of the proposed system. For instance, if you want to
develop a radically new system that is expected to launch payloads for $10
a pound less than the Shuttle (and assume comparable payload sizes to make it
simple), but the new system will cost $10 billion to develop, then you have
to show that the $10/lb saving on payload will make up for the $10 billion
new development cost. I'd say there's a good chance that the DC approach
can meet this criterion, but those are the numbers it has to beat, not
just a "level playing field" comparison of operational costs or of
operational + development costs for both.

(Unless the government decides to pay for the development of DC - but
that decision would hardly be an argument for the financial merits of DC.)

Of course the Shuttle is still "under development" to some extent (i.e.
the ASRM), but I believe those costs are included in the ~$4 billion/year.

If you want, you can bring up the possibility that payload costs will also
be reduced using a DC system, but that's a separate issue.

->You have done the 'creative accounting' here, I'd say.

-No, it's NASA who is being creative by ignoring billions in cost. BTW,
-if a private company ran their books the way NASA does they would be
-thrown in jail for fraud.

Interesting side note - some people (I don't recall who) have implied
that a private company doing its accounting in the military/NASA style
would get in trouble with the *IRS*. That seems a little farfetched - I'd
think the IRS would be *happy* if companies declared taxable income that
they didn't really earn. Of course, the *stockholders* might not be too
happy... :-)

John Roberts
[e-mail]

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

Date: 22 Dec 92 22:46:50 GMT
From: "Joel K. Furr" <[e-mail]>
Subject: asteroids beyond Jupiter
Newsgroups: alt.folklore.urban,sci.space

In article <[e-mail]> [e-mail] (bill nelson) writes:
>[e-mail] (Dave Jones) writes:
>: bill nelson ([e-mail]) wrote:
>: > :
>: > : Sorry, Bill, but there are many planetoids and asteroids that orbit beyond
>: > : the orbit of Jupiter.  One such is a minor planet called Chiron.  There
>: > : are quite a few others as well.
>: >
>: > Note that I said "pretty much".
>: >
>: > There certainly are some that travel outside the orbit of Jupiter - as well
>: > as inside the orbit of the Earth. However, I know of none that travel outside
>: > the orbit of Saturn, much less any of the planets further out.
>: >
>: > Bill
>:
>: Well, stay tuned.  Object 1992QB1 is reckoned to be a good candidate for a
>: distant (40-50 A.U.) minor planet and may be the first of many discovered at
>: that distance.
>
>The statement was asteroid - not planetoid. The asteroids originate in the
>asteroid belt. It is doubtful if any of them could be perturbed enough to
>reach the orbit if Neptune.
>
>The planetoids are a different matter. It is possible that some of them
>came from outside the Solar System. They could also have been formed just
>about anywhere in the system, so the same limitations do not apply to
>them. I would not argue that a planetoid could not have been captured
>by Neptune - although the fact that Pluto has a moon makes this very
>unlikely.

No, Bill, you're wrong.  There are many flat-out ASTEROIDS that orbit that
far.  You're not an astronomer, don't lecture us from a vacuum of knowledge.

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

Date: 23 Dec 1992 00:21:46 GMT
From: David Smith <[e-mail]>
Subject: Aurora chase planes (was Re: Aurora)
Newsgroups: sci.space

I think people are getting a little too hung up on the "chase" word.
If I recall right, what started this was that an observer said he
saw this unidentified plane being chased by an F-15 or F-16.  As
an observer, how can you tell if one plane is "chasing" another or
accompanying it?  (Mary's definition of "chase plane" is the standard
one for testing aircraft but we're really talking about an "accompanying
plane")  Unless there was some major manuevering going on you can't say
that the F-15 was "chasing" or attempting to intercept with the intent
of shooting it down or identifying an unknown plane rather than accompanying
it as a "chase plane".
--
David L. Smith
[e-mail] or [e-mail]

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

Date: Tue, 22 Dec 1992 23:48:34 GMT
From: Henry Spencer <[e-mail]>
Subject: Breeders
Newsgroups: sci.space,sci.physics

In article <[e-mail]> [e-mail] (Craig "Powderkeg" DeForest) writes:
>...In Canada, they don't enrich their uranium at all for
>the CANDU reactors -- by using heavy water as a moderator, they
>improve the fission efficiency to where natural uranium is sufficient.

Actually, not quite true.  The CANDU can burn natural uranium quite
happily, but it's somewhat more efficient with slightly-enriched uranium,
and that's what our CANDU power reactors normally use.  If it became
costly or hard to get, we'd switch.
--
"God willing... we shall return."       | Henry Spencer @ U of Toronto Zoology
       -Gene Cernan, the Moon, Dec 1972 |  [e-mail]  utzoo!henry

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

Date: 23 Dec 92 02:03:19 GMT
From: Craig Keithley <[e-mail]>
Subject: DC vs Shuttle capabilities
Newsgroups: sci.space

In article <[e-mail]>, [e-mail]
(Edward V. Wright) wrote:
>
>
> No, we're being misquoted.  What we actually said was, "Lead,
> follow, or get the hell out of the way."
>

   Ok, I've got it... Because you feel SSTO/DC-? is the only way to go, you
think we should either
  (a) accept your points and participate in leading the charge for
SSTO/DC-?
      -or-
  (b) follow you blindly and accept what your saying about DC-?
      -or-
  (c) get out of the way and let you redistribute the $$$ in a way we
      disagree with.

   What if we don't accept your points, don't want to follow you (blindly)
and and don't want you to redistribute the $$$ in a way we disagree with?

   As an example, I believe that doing science on Mir is a bad idea.
Political winds change direction quickly.  Putting our scientific eggs in
that basket, and having that basket tip over is not something I relish.  I
also have other questions about accounting methods, having Nasa pay for
another Canadarm, etc., etc.  But I'll shelve those for now...

   I've followed the discussion and exchanged email with Allen (et. al.)
privately. I would like to suggest something (different?):

        Lets see a straw man proposal that clearly indicates (using the
published Shuttle schedule for the next few years) when the Shuttle would
go "off-line", what alternatives would be used for it, how much/if SSF
would slip, when DC-1 would come on-line and so forth.  Show timelines,
costs, changes in costs, etc.  If we're going to replace a Shuttle launch
with a Titan IV, estimate lead time to acquire that Titan and so forth.
I'll assume that all the range safety questions have been answered.

   If the Shuttle "detractors" wish, produce a schedule that replaces every
Shuttle flight starting with the next one.  This would used purely as a
center for discussion, because it would have to ignore the political
realities with cancelling the shuttle *today*.

   Then lets see a long term version.  In the case, I'd appreciate some
sense of political reality.  Insistance that we really can stop flying the
shuttle immediately will do nothing except convince me that you aren't
grounded in reality.

   Because I've grown tired of arguing philosophy (and listening to
arguments).   Lets argue over which specific Shuttle mission can, or cannot
be replaced.  This endless frothing, which I've participated in, serves
little purpose (other than as a questionable sporting activity).

thanx,

Craig Keithley
Apple Computer, Inc.
[e-mail]
"I have absolutely no responsibility in this matter, what-so-ever"

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

Date: Tue, 22 Dec 1992 23:43:34 GMT
From: Henry Spencer <[e-mail]>
Subject: ground vs. flight
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Greg Moore) writes:
>    I can recall only 1 (possibly 2) examples of astronauts
>transferring between craft via EVA.  And in that case I believe
>the craft were linked...
>    I don't doubt that someday we'll see EVA between
>non-docked craft...

"Someday" was 1966, on Gemini 10.  And the target craft for the EVA wasn't
even stabilized -- it was an old Agena, batteries long since dead.  Apart
from the problems of EVA itself, which NASA was only just starting to
discover, it wasn't a problem according to Michael Collins (who did it).

You might also want to look up the Solar Max retrieval (as originally
planned), the Palapa/Westar retrieval, and the Leasat repair, all of
which involved astronauts interacting with undocked craft.  The Leasat
repair, in particular, was done by the Intelsat method:  slide the
shuttle up close to the satellite and have an astronaut grab it (and
Leasat was spinning, too).

By the way, why do you assume the craft wouldn't be linked before crew
or cargo transfer?  It would make sense to at least have an arm linking
them first.

On-orbit operations are a little bit harder than on-ground operations,
for two reasons:  lack of friction, and the extra dimension of motion.
On the ground, before you refuel (say) an aircraft, you make sure it's
parked with its brakes locked.  The equivalent in orbit is to grab hold
of it with an arm.  Still lots easier than for aircraft in flight.
--
"God willing... we shall return."       | Henry Spencer @ U of Toronto Zoology
       -Gene Cernan, the Moon, Dec 1972 |  [e-mail]  utzoo!henry

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

Date: Tue, 22 Dec 1992 23:29:11 GMT
From: Paul Dietz <[e-mail]>
Subject: Justification for the Space Program
Newsgroups: sci.space,talk.politics.space

In article <[e-mail]> [e-mail] writes:

 > I will no longer debate you on this subject. You have your "opinions",
 > which is all your responses to date have been, and I have mine. You
 > work for your worldview and we will work for ours.
 >
 > You speak of quasi-religiousness when the exact same thing can be said
 > of your asserations.

Oh, *please*.  I've posted numerous quantitative arguments in rebuttal
to your claims.  I can even provide references for those numbers, if
you'd like.

 > I have work to do. I live in the real world. If you actually think
 > things are getting better from a world perspective then you are truly
 > blind. This is a simple fact, not a flame.

By most objective measures, the world is getting better.  The world
has never been, on average, wealthier, healthier, better fed, or
better educated than it is today.  These are *facts*.  You can look up
the numbers.  These trends have been going on for decades, in spite of
the continuous (and continuously wrong) doomsaying.

    Paul F. Dietz
    [e-mail]

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

Date: Tue, 22 Dec 1992 21:16:24 GMT
From: Mike Kirby <[e-mail]>
Subject: Justification for the Space Program
Newsgroups: sci.space

In article [e-mail], [e-mail] (Paul Dietz) writes:
>In article <[e-mail]> [e-mail] writes:
>>In article <[e-mail]>, [e-mail] (Paul Dietz) writes...
>
>>>I asked Wingo to bring up a resource that could be obtained from
>>>space that was not substitutable, used in small quantities so that
>>>price rises could be tolerated, or in short supply.   He suggested
>>>platinum.
>>
>>Paul Platinum is only one of many metals that, if we have at a minimum, a
>>translunar transporation system would be cheaper.
>
>So, trot out your claims so I can shoot them down.  And no more
>of that lunar titanium nonsense, ok?  I debunked that last time.
>
>BTW, it is *not* obvious that having a translunar transportation
>system would make platinum group mining economical.  This system would
>have costs, which could be high, as would the mining operation.  Since
>the market for platinum is rather small (a few billion $/year), it by
>itself cannot justify much space activity.
>
>
>
>    Paul F. Dietz
>    [e-mail]
>

Okay,  I'll give it a shot.

Given the assumption that we want to build large structures in space
and on other planets, It seems that the mining of minerals in space for
use in space would be profitable because of the huge gravity hole that
you have to haul the stuff out of.  If we want to do any large scale
construction in space I would think the materials would have to come
from space if we want to build anything for a reasonable price.

Another interesting point might be that new mining techniques for "off world"
mining might prove useful in squeezing more out of currently unproductive
mines on earth.

Of course why we would want to build any large scale construction in space in
the first place is an entirely different discussion.

Mike Kirby
Xerox Corp
E-mail: [e-mail]

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

Date: 23 Dec 92 02:51:13 GMT
From: Greg Moore <[e-mail]>
Subject: Justification for the Space Program
Newsgroups: sci.space,talk.politics.space

In article <[e-mail]> [e-mail] (Brad Whitehurst) writes:
>>
>    Well, Paul, I won't even try to convince you with facts.  We'd
>still have flat-earthers if somebody hadn't run out to the "edge" and
>tried jumping off, despite all the great Greek geometry.

    Actually, before you start blaming the Greeks, keep in mind
that they had a good idea the earth was curved.  They even developed
a rough approximation of the diameter based on the shadow of the sun.

    It was a Greek (the name escapes me) that described a
heliocentric solar system.  Unfortunately Plotemly had better press.

>
>--
>
>Brad Whitehurst    |   Aerospace Research Lab
>[e-mail] |   We like it hot...and fast.

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

Date: 22 Dec 92 23:58:04 GMT
From: Henry Spencer <[e-mail]>
Subject: LEI financing
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Ross Borden) writes:
>    However, I have a problem with funding by donation.  I would be willing
>to donate ~$100.  But, if I had a reasonable expectation of getting my money
>back, I would be willing to invest several $1000.  I wouldn't be greedy about
>it either.  I would be satisfied to get the principle back at the end of the
>mission.  Call it a 3-4 year no interest loan.
>    I suspect that there would be many other space enthusiasts who would
>be willing to 'loan' sizable pieces of change on this basis.

There would be absolutely no problem financing something like this if a
reasonable return on investment seemed reasonably likely.  It wouldn't be
necessary to gather a thousand here and a thousand there; it could be done
as a straight commercial venture with venture-capital funding.  Alas, there
is no adequate market apparent right now.  At present, you can't make
*Earth* remote-sensing satellites pay for themselves that way, never
mind lunar ones.

>... Could you talk NASA into buying the whole thing for
>,say, $20M ?

NASA would much rather spend (say) $50M doing it themselves than pay
$20M for the data, given the choice.  (Remember, NASA's first priority
in practice is jobs, not results... and they like to be in control.)

>(I recall a proposed bill called something like "Lunar Resources
>Information Purchasing Act" by which the US government would require NASA to
>purchase the first available lunar resource map.  What happened to it?  Did it
>die, or is there still a chance of passing it?)

It's in the works; you'll see more about it in the next few months.  I'm
afraid I don't have very high hopes for it passing, although it's worth
a try.
--
"God willing... we shall return."       | Henry Spencer @ U of Toronto Zoology
       -Gene Cernan, the Moon, Dec 1972 |  [e-mail]  utzoo!henry

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

Date: 22 Dec 92  09:53:36
From: [e-mail]
Subject: LEI financing
Newsgroups: sci.space

If funding for lunar sciences is a problem, why not convince your American
colleagues to support the Lunar Resources Data Purchase Act? This new
legislation would provide a funding base for a series of lunar polar orbiters.


--- Maximus 2.01wb

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

Date: 23 Dec 92 00:01:23 GMT
From: Henry Spencer <[e-mail]>
Subject: Lunar Resource Mapper Status (Was Re: funding for Lunar Prospector)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:
>Also the 32 million requested was not to "get started". It was for the entire
>satellite. This did not of course cover the other costs such as the launch
>or operations.

The $30M in question was first-year funding to get Griffin's entire effort
started; this was to include the beginnings of the mapper project, which
would end up costing $30M or so for the spacecraft proper.

Griffin didn't get it.
--
"God willing... we shall return."       | Henry Spencer @ U of Toronto Zoology
       -Gene Cernan, the Moon, Dec 1972 |  [e-mail]  utzoo!henry

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

Date: 23 Dec 92 02:26:00 GMT
From: [e-mail]
Subject: Lunar Resource Mapper Status (Was Re: funding for Lunar Prospector)
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Henry Spencer) writes...
>In article <[e-mail]> [e-mail] writes:

>The $30M in question was first-year funding to get Griffin's entire effort
>started; this was to include the beginnings of the mapper project, which
>would end up costing $30M or so for the spacecraft proper.
>
>Griffin didn't get it.
>--

The money is coming from JSC internal funds as well as left over funds from
other operations at Griffin's code. I repeat the project is not dead as of
this time. It might well be if the new congress critters say that NASA can't
spend the money that is available, but this has not happened. This money
also does not affect the Lunar Geophysical Explorer which is not part of SEI.
It seems that you can get money as long as the SEI tag is not attached. Heck
there is 5 million dollars this year for the Lunar power beaming project and
money is being spent even now for the Lunar far side telescope project. It
helps to be where you can hear these things.

Dennis, University of Alabama in Huntsville.

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

Date: 22 Dec 92 23:31:44 GMT
From: Henry Spencer <[e-mail]>
Subject: MOL (and Almaz)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:
>What were the results of the "heatshield with a hatch in it" tests?
>Did it work?  That sure would be one door that you wouldn't want to
>open at the wrong time. :-)

To the considerable surprise of some observers, there wasn't the slightest
problem with the hatch-equipped heatshield.
--
"God willing... we shall return."       | Henry Spencer @ U of Toronto Zoology
       -Gene Cernan, the Moon, Dec 1972 |  [e-mail]  utzoo!henry

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

Date: Wed, 23 Dec 1992 03:39:16 GMT
From: "Allen W. Sherzer" <[e-mail]>
Subject: People who can't count costs (Was Re: Terminal Velocity of DCX?)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:

>The marginal cost for a Space Shuttle mission is $37 million dollars maximum.

Since Shuttle is flying at its maximum rate the marginal rate of a flight
is completely irrelevant.

>For those who are further mentally deranged and who love to count more of
>the costs to the Shuttle program, the figure is $368 million dollars.

In November of 1992 the Aldridge Commission completed its report on the
future of US space launch capability. Their conclusion (see page 21) was
that a total of about $5 billion is spent each year "being devoted
exclusively to Shuttle operations to support only seven ti eight flights
per year". From this figure it is very easy to show that a Shuttle
flight costs well over half a billion.

Now do you actually consider Mr. Aldridge, president and CEO of The
Aerospace Corporation, and his commission "mentally deranged"? If so
perhaps you could share with us all just how you came to this conclusion.
If not, then how do you justify your own figures?

>ONLY if you take every single budget item in the entire NASA budget that has
>any relationship to manned space activities and then divide by the number
>of flights per year, then you will get a >$500 million per flight costs.

Not according to Aldridge.

>These numbers come from the Space News article of Nov 29 December 8. Where
>the heck do your numbers come from?

I believe you have misread the Space News article.

>By the way, it is too bad Allen did not have the guts to respond to my
>previous message relating these figures.

Largely because you have misread the article. That article quoted a NASA
spokesperson as saying the cost was $550 million per flight simply by
dividing flight rate by operational costs. Adding in all manned flight
activites was done by somebody outside of NASA (John Pike?) and produced
not the $500M you quote above but a figure of about $750M.

Sit down, take a valium, and re-read the article. Then read the Aldridge
report (unless of course you actually do think he is 'mentally deranged').

>I am flat sick and tired of people
>simply ignoring any information that is detrimental to their little pet
>project, no matter how valuable that project is in and of itself.

Indeed.


  Allen
--
+---------------------------------------------------------------------------+
| Allen W. Sherzer | "A great man is one who does nothing but leaves        |
|  [e-mail]     |  nothing undone"                                       |
+----------------------153 DAYS TO FIRST FLIGHT OF DCX----------------------+

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

Date: 23 Dec 1992 00:36:23 GMT
From: David Smith <[e-mail]>
Subject: SSTO vs. 2 Stage
Newsgroups: sci.space

There's an advantage (I believe) of SSTO vs multi-stage systems that's
getting left out here.  When launching a DC-1 all the engines are started
and then throttled up.  This means that if an engine refuses to start,
OR if there is a major fuel system problem such that none of the engines
will start you can abort the launch on the pad.  With the two-stager
enough engines have to start at separation time to assure that the DC-1
can at least abort.

I would assume that engine start is when things are most likely to go wrong.
This means you have to be extra careful to check all the things related to
engine starting, etc.  (I'm not sure how to categorize the risks in
restarting the engines to de-orbit.  Is it less risky than the initial
start because the engines have already run once or is it equally or
more risky?  There is the option of an EVA to repair engines in orbit
but you don't have all the spares, equipment or trained personnel you would
on the ground)

The DC-0 stage should also have the capability to abort and land with
an attached DC-1 which means extra fuel that normally won't be used, or
some whomping big parachutes, or ...


--
David L. Smith
[e-mail] or [e-mail]

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

Date: 23 Dec 92 02:57:44 GMT
From: Bruce Dunn <[e-mail]>
Subject: SSTO vs. 2 Stage
Newsgroups: sci.space

> David Smith writes:
>
> There's an advantage (I believe) of SSTO vs multi-stage systems that's
> getting left out here.  When launching a DC-1 all the engines are started
> and then throttled up.  This means that if an engine refuses to start,
> OR if there is a major fuel system problem such that none of the engines
> will start you can abort the launch on the pad.  With the two-stager
> enough engines have to start at separation time to assure that the DC-1
> can at least abort.

     Agreed.  Failure of second and third stage engines of conventional
launchers to ignite after staging has historically been a common cause of
launch failures.  However, I presume that the DC-1 will have the capability
of surviving at least 1 engine failure when at near maximum fuel load
(otherwise failure of any one out of multiple engines would cause a crash in
the period immediately following an SSTO takeoff).  If the DC-1 can survive
an engine shutdown after launch in SSTO mode, it seems to me that it should
be able to survive the failure of an engine to start after separation from a
booster.  Remember that since the DC-1 already has considerable upwards
velocity, it has time to burn off fuel, even with only some of the engines
operating, to get its weight less than its thrust.
        I grant that no amount of engine out capability will help a DC-1 if
it separates from the booster and none of the engines fire because of a fuel
problem.


--
Bruce Dunn    Vancouver, Canada   [e-mail]

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

Date: Tue, 22 Dec 92 18:47:05 PST
From: Brian Stuart Thorn <[e-mail]>
Subject: Terminal Velocity of DCX? (was Re: Shuttle ...)
Newsgroups: sci.space

>In article <[e-mail]> [e-mail] (Edward V.
>Wright) writes:
>>
>>>The average total cost of a shuttle mission is a little over $500 million
>>>not a billion+.
>>
>>Only if you learned math from the "Hitchhiker's Guide."
>>
>        Do you think it is possible for you to reply to a person's posting
>without being insulting or condescending?
>
>>Divide the amount of money NASA spends on the Space Shuttle program
>>every year by six flights per year.
>>
>        Right, except last year they fley 8 times.  This year they
>have 7 planned.
>
         Eight.
         STS-54 (TDRS-F, Jan), STS-55 (Spacelab D2, Feb),
         STS-56 (ATLAS-2, Mar), STS-57 (EURECA, Apr)
         STS-51 (ACTS, Jul), STS-58 (SLS-2, Aug)
         STS-60 (WSF, Nov), STS-61 (HST REPAIR, Dec)

         -Brian

-------------------------------------------------------------------------
Brian S. Thorn                                    "If ignorance is bliss,
[e-mail]                               this must be heaven."
                                                -Diane Chambers, "Cheers"
-------------------------------------------------------------------------

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

From: Craig Powderkeg DeForest <[e-mail]>
Newsgroups: sci.space

Subject: Re: Breeders
In-Reply-To: [e-mail]'s message of Tue, 22 Dec 1992 02:46:14 GMT
Message-Id: <[e-mail]>
Followup-To: sci.physics
Sender: [e-mail]
Organization: Stanford Center for Space Science and Astrophysics
References: <[e-mail]>
Distribution: sci
Date: 22 Dec 92 14:18:04
Lines: 46
Source-Info:  Sender is really [e-mail]
Source-Info:  Sender is really [e-mail]

In article <foo> [e-mail] ("Phil G. Fraering") writes:
   \Session's Answer was too flipant.  The reason the U.S. doesn't hav mre
   /ooops have more breeder reactors is that the anti-nuke forces won a battle
   \in the late seventies and President Jimmy Carter stopped the development
   /of them.  The arguements given revolved around the proliferation of
   \Plutonium that the reactors "breed" and not on the safety of the
   /reactors.  The nuke power industry was trying to sell them as the answer
   \to lmited supplies of nuclear fuel (o.k. expensive supplies) because they
   /produce 5 lbs of fuel for every 4 they consume.  Unfortunately, the
   \plutonium is also a great nuke weapon resource.

   From what I've heard, it's the wrong isotope or mixed with such as
   to be useless in constructing a nuclear bomb.

What the Carter Administration stopped was reprocessing plants.  In
order for breeder reactors to breed, you've gotta separate out the new
fuel from the miscellaneous fission products (some of which are highly
radioactive) that accumulate in the fuel.

In fact, if you have a reprocessing plant, you win big regardless of
whether you're running a breeder, because the limiting factor in fuel
rod use is buildup of neutron-absorbing fission products, *not* loss
of the fuel isotope.  I haven't got my books handy, but I think it's
around a factor-of-ten or more. (ie <10% of the fuel is used up, when
the rod can no longer be used.)

In fact, one of the issues surrounding the reprocessing plant thaang
was the development of a viable nuclear bomb design by a Princeton
undergraduate student. (whose name I forget.  John Archibald?)  He did
it to prove that a sufficiently motivated terrorist could build one,
if only he could get his hands on some plutonium.  He was contacted by
intelligence agents from Iraq!  (This was back before they were our
friends, before they were our enemies.  They had, of course, just
bought their `peaceful' nuclear reactor from the French.)  The Carter
Administration blocked the development of a reprocessing plant,
largely (they said -- I'm sure general anti-nukular paranoia helped)
because it would entail shipping large amounts of reprocessed fuel
(including plutonium) around, and there was danger of hijacking.

Note that it's relatively easy here in the U.S. to get slightly
enriched Uranium (<20% U-235), but it's very hard to get anything
more pure.  In Canada, they don't enrich their uranium at all for
the CANDU reactors -- by using heavy water as a moderator, they
improve the fission efficiency to where natural uranium is sufficient.
--
DON'T DRINK SOAP! DILUTE DILUTE! OK!

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End of Space Digest Volume 15 : Issue 587
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