HDTenEightyP/NetNews huggingface dataset:
From: tjn32113@uxa.cso.uiuc.edu (Thomas J. Nugent)
Subject: Re: Antiproton-Boosted Microfission (was: Antimatter ...)
Organization: University of Illinois at Urbana
Date: Thu, 23 Jul 1992 20:20:18 GMT

bwood@diva.Berkeley.EDU (Blake Philip Wood) writes:

>All the postings so far have missed the most realistic application of
>antimatter to space propulsion:  antiproton-boosted microfission.
>This is being investigated by a number of folks at Penn State, in
>collaboration with some people at Phillips Lab in Albuquerque.
>The Penn State lead is R.A. Lewis.  The reference I happen to have 
>on hand is from Nuclear Science and Engineering, (109) p.411 (1991).

>The basic idea is that hitting a U235 or Plutonium nucleus with an
>antiproton makes it so unstable that you get an average of 16 neutrons
>out of the resulting fission, as opposed to the usual 2-3.  This means
>that the critical mass which can be completely fissioned is very
>small.  The paper I referenced above discusses using an ICF
>arrangement to compress a Plutonium pellet, then irradiate it with 
>antiprotons at peak compression.  The advantage of this approach
>is that you can do it with quantities of antimatter which can be
>produced today in large accelerators.  The article above quotes
>results from another paper which suggests that fissioning one
>70mg Plutonium pellet per second in this fashion, each event requiring
>only 2e8 antiprotons, could yield 5GW of power in a complete propulsion
>system with a specific mass of only 0.07 kg/kW.

Well, since everyone seems so interested in antimatter's use in propulsion,
and the above was posted, I'll add my own $0.02+tax.  I was a co-op out
at JPL last year, and I did a little performance evaluation of antiproton
induced fusion rockets (it was compared to the VISTA laser ICF fusion rocket).
This was entirely based on the work at Penn State by Lewis, Smith, and others.
The idea was as above, except for one additional bit.  The antiprotons were
used to induce microfission (i.e., relatively small fission explosions),
which in turn produced fusion in the fusile fuel.  Alot like a hydrogen
bomb, I guess you could say (meaning, use fission to produce fusion).  
Alot of the study is still in its early stages, but within the next few years
the experiments at Phillips Lab should be producing the data they need to
evaluate how effective this really is.  

Because of the large uncertainties, a definite conclusion could not be
reached.  However, the concept does show promise, and could prove useful
in a variety of missions. 
-----
"Far better it is to dare mighty things, to win glorious triumphs, even
though checkered with failures, than to rank with those poor spirits who
neither enjoy nor suffer much, because they live in the gray twilight that
knows not victory nor defeat."
		- Theodore Roosevelt 

-- 
"To be average scares the hell out of me." -- Anonymous
Tom Nugent		e-mail: tjn32113@uxa.cso.uiuc.edu
Newsgroups: sci.space
From: dp10@mc4adm.UWaterloo.ca (Derek Kirkland)
Subject: Canadian comments
Originator: dp10@mc4adm.UWaterloo.ca
Organization: University of Waterloo
Distribution: na
Date: Wed, 29 Jul 1992 18:35:25 GMT

If Canadians are not supposed to have comments on internal US politics,
why do the major US networks hire lots of Canadians as their main
news program anchors. These Canadians are allowed to make lots of comments on US
politics and no one seems to complain.


The whole idea that "foreigners" should not comment on internal US
politics is the most ridiculous statement I have heard in years.
From: 3728P@CC.NPS.NAVY.MIL
Newsgroups: sci.space
Subject: Astronomy Program
Date: 22 Jul 92 18:43:57 GMT
Article-I.D.: cs.1992Jul22.184612.158881
Distribution: sci
Organization: [via International Space University]
X-Added: Forwarded by Space Digest
Original-Sender: isu@VACATION.VENARI.CS.CMU.EDU

Hi Everybody,

  I joined the list after a friend told me about it.
Anyway, I missed to info about the Astronomy Program
for Windows.  Can someone email it to me privately,
unless there is enough people still interested to
post it here again...

*==================================================================*
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*                          Internet: 3728p@CC.NPS.NAVY.MIL         *
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From: kellmer@milton.u.washington.edu (Brent Kellmer)
Newsgroups: sci.space
Subject: Glaciation on Mars
Date: 29 Jul 92 19:23:04 GMT
Reply-To: kellmer@u.washington.edu
Organization: University of Washington, Seattle

Perhaps someone out there could help me with a problems:

I'm trying to find out if there is any evidence for past glaciation on
Mars.  Any input?

Thanks.

Brent Kellmer 
kellmer@u.washington.edu
Newsgroups: sci.space
From: phk@aristotle.Jpl.Nasa.Gov (Pieter Kallemeyn)
Subject: Re: Galileo Update - 07/20/92
Keywords: Galileo, JPL
Organization: Jet Propulsion Laboratory, NASA/Caltech
Date: Tue, 21 Jul 1992 15:24:17 GMT

In article <1992Jul20.230933.2346@cco.caltech.edu> kwp@wag.caltech.edu (Kevin W. Plaxco) writes:
>In article <1992Jul20.193308.16649@news.arc.nasa.gov> baalke@kelvin.jpl.nasa.gov writes:
>
>>     Tomorrow, the turn to the warming attitude in preparation for the Dual
>>Drive Actuator (DDA) pulse is scheduled to begin at approximately 10:57PDT.
>>The first of the two Dual Drive Actuator pulses is scheduled at 12:46 PDT for
>>approximately a 2 second duration.  Tracking is scheduled over DSS-43.
>
>This, I presume, represents an attempt to free the HGA by using the LGA-2
>deployment motor to shake the S/C.  Presuming this is correct: How many
>pulses can be generated in 2 seconds? Is this just a test of the pulse
>proceedure, and therefore limited to one stow/deployment cycle?  And
>why is this being done at the warming attitude since the HGA is less tightly
>stuck when cold?
>
>-Kevin

The warming turn is for the benifit of the DDA motor itself, which works
better at higher temperatures.  As for the number of pulses, there will be 
only one on/off cycle for this 2-second duration test.  Another 2-second 
on/off cycle is planned a few days later after the DDA motors have had a chance
to warm.
--
Pieter Kallemeyn                     |   phk@aristotle.jpl.nasa.gov
Jet Propulsion Laboratory            |          - or - 
California Institute of Technology   |   phk@cabrilho.jpl.nasa.gov
From: amon@elegabalus.cs.qub.ac.uk
Newsgroups: sci.space
Subject: Re: Whales and Dolphins
Date: 23 Jul 92 10:53:24 GMT
Article-I.D.: cs.1992Jul23.105414.31741
Distribution: sci
Organization: [via International Space University]
X-Added: Forwarded by Space Digest
Original-Sender: isu@VACATION.VENARI.CS.CMU.EDU

> I don't doubt you're right, but other less intelligent animals will  
sometimes
> do this too, particularly the "bachelor groups" as you describe.  
I've heard of
> groups of male lions attacking a dominant male to get territory or  
mates,
> then fighting among themselves. There are extensive studies of  
possible
> evolutionary incentives to form specific behavior patterns.
> 


There is a difference. You are talking about a group breaking up in a 

free for all. Dolphins are the only other society in which GROUP A 

gets support of GROUP B against GROUP C for a specific project but
when the situation changes, GROUP A will double cross GROUP B with 

the assistance GROUP C. The groups are basically stable. I do not
remember enough details of the paper to say whether they are kinship 

groups or not. The situations do not appear to be random accident,
but much more sophisticated plotting of actions. Probably closer to 

the relations between feudal lords than to a gang of hoods who fight
for the loot among themselves after cooperating to get it...


 
Newsgroups: sci.space
From: henry@zoo.toronto.edu (Henry Spencer)
Subject: Re: Methods for meteor avoidance
Date: Fri, 24 Jul 1992 16:25:01 GMT
Organization: U of Toronto Zoology

In article <a6cf4fff@Kralizec.fido.zeta.org.au> brendan.woithe@f820.n680.z3.fido.zeta.org.au (Brendan Woithe) writes:
>After the meteor from last year passed withinn 4 minutes of the earth (the
>large one), I was wondering if we have any system of avoiding these 
>large beasts??!! ...
>With a problem like this, surely there must be some defence!!!

There has been discussion of this, both in the past and recently.  The big
problem is detecting them far enough in advance.  Given adequate advance
warning, one could use large nuclear bombs to destroy or deflect the incoming
rock, in principle.  There is a practical problem in that the US currently
has no launcher adequate to the job; there are some things for which there
is no substitute for a Saturn V or equivalent.
-- 
There is nothing wrong with making      | Henry Spencer @ U of Toronto Zoology
mistakes, but... make *new* ones. -D.Sim|  henry@zoo.toronto.edu  utzoo!henry
From: burns@latcs1.lat.oz.au (Jonathan Burns)
Newsgroups: sci.space,rec.arts.sf.science
Subject: Relativity in science fiction
Date: 27 Jul 92 12:37:41 GMT
Followup-To: rec.arts.sf.science
Organization: Comp Sci, La Trobe Uni, Australia

In article <9207250444.AA14607@cmr.ncsl.nist.gov>
 roberts@CMR.NCSL.NIST.GOV (John Roberts) writes:

> That's from Galactic Patrol, which was copyrighted in 1937 and 1950 (this
> comment may have been added at the later date). (I believe this was the
> first book written, though it's the third of the series.)

> I've wondered about the chronology of the "negaspheres" (first appearing
> in the series in 1951, and apparently equivalent to antimatter black
> holes) and the development of theories on black holes. When did serious
> theorization on black holes come along?

Pulsars were discovered in, um, 1964? In the late 60s there were
conferences - Wheeler and de Witt edited the proceedings for one,
as I recall - on general relativity, the equation of state for
neutron stars, there being no stable state for them above a certain
mass. The name 'black hole' dates from then.

Smith's negaspheres would have come from the Dirac Sea idea.
Dirac's equation allows negative-energy states for electrons; but then
why don't all the electrons fall into them? Ans: they are all filled,
and the Exclusion Principle prevents it. A hole in the sea is a positron.

Negative-energy electrons on the loose were never predicted. Doc confused
the annihilation property of antimatter with the negative-intertia
property of loose n-e matter.


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Jonathan Burns        | His wit never failed him, and he laughed
burns@latcs1.lat.oz.au| himself to death over a book of the dying
Computer Science Dept | a words of famous men.
La Trobe University   |                  Disch, _Camp Concentration_
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
From: rmartin@thor.Rational.COM (Bob Martin)
Newsgroups: sci.space
Subject: Re: Propulsion questions
Date: 22 Jul 92 19:55:55 GMT

nickh@CS.CMU.EDU (Nick Haines) writes:

>In article <rmartin.711737055@yosemite> rmartin@yosemite.Rational.COM (Bob Martin) writes:

>   [about a black-hole drive]

>   Can anybody tell us the efficiency of this with respect to a fusion
>   drive?

>I can guarantee that the answer to that question is "no". I mean, it
>might be a neat idea, but we're not going to have a decent figure for
>the efficiency of it until we've actually got a small black hole to
>play with.

Allright then, does anybody have a theoretical model that might shed
some miniscule light on this subject?   (Sheesh!)


--
+---Robert C. Martin---+-RRR---CCC-M-----M-| R.C.M. Consulting         |
| rmartin@rational.com |-R--R-C----M-M-M-M-| C++/C/Unix Engineering    |
|     (Uncle Bob.)     |-RRR--C----M--M--M-| OOA/OOD/OOP Training      |
+----------------------+-R--R--CCC-M-----M-| Product Design & Devel.   |
Newsgroups: sci.space
From: tom@vexcel.com (Tom Baltzer)
Subject: Re: ESA Future
Organization: VEXCEL Corporation, Boulder, CO
Date: Wed, 22 Jul 1992 20:57:56 GMT

I heard today that ESA's ERS-1 Satellite has been down since July 16th
or so.   Anyone else hear this?   Anyone know the scoop?  It appears that
they are being fairly tight lipped about it, (given this thread it's not
too surprising).  Any info would be appreciated.


Tom.
From: higgins@fnala.fnal.gov (Bill Higgins-- Beam Jockey)
Newsgroups: sci.space
Subject: Re: Methods for meteor avoidance
Date: 27 Jul 92 13:00:08 GMT
Organization: Fermi National Accelerator Laboratory

In article <1992Jul26.071133.18449@metapro.DIALix.oz.au>, bernie@metapro.DIALix.oz.au (Bernd Felsche) writes:
>>In article <a6cf4fff@Kralizec.fido.zeta.org.au> brendan.woithe@f820.n680.z3.fido.zeta.org.au (Brendan Woithe) writes:
>>>After the meteor from last year passed withinn 4 minutes of the earth (the
>>>large one), I was wondering if we have any system of avoiding these 
>>>large beasts??!! ...
>
> For very large meteors, it may actually be more practical to
> subtly change our own orbit (not through nuclear explosions!),
> though the environmental impact of doing this is mind-blowing.

ANNOUNCER: "Innumeracy-- it doesn't just strike Americans. 
It's a global problem."

Bernie's statement is true-- for all "meteors" more massive than the
Earth. Fortunately, such meteors are rare.  We know of only five in
our Solar System, and only one has ever passed closer than 100 million
miles.

> How we change the orbit is left as an exercise for the student. :-)

I claim that any method which works for changing the Earth's orbit,
works even better for changing the asteroid orbit, as long as the
asteroid's mass is less than 6E24 kg.  Flame me if I'm wrong.

ANNOUNCER: "Once, Innumeracy was thought to be a rare disease.  But
now, in just a short time, it has spread to afflict, um, very many
people... in a lot of countries across the globe.  Please give to the
Campaign Against Innumeracy.  We're Counting On You."

During the first and second stage         Bill Higgins   
flights of the vehicle, if a serious      Fermi National Accelerator Laboratory
irretrievable fault should occur and      HIGGINS@FNALB.BITNET
the deviation of the flight attitude of   HIGGINS@FNAL.FNAL.GOV
the vehicle exceeds a predetermined       SPAN/Hepnet: 43011::HIGGINS 
value, the attitude self-destruction
system will make the vehicle
self-destroyed. 
     --Long March 3 User's Manual
     Ministry of Astronautics, People's Republic of China (1985)
From: UC369801@MIZZOU1.missouri.edu (Walker on Earth)
Newsgroups: sci.space
Subject: Whales (SETI)
Date: 28 Jul 92 16:15:28 GMT
Distribution: sci
Organization: [via International Space University]
X-Added: Forwarded by Space Digest
Original-Sender: isu@VACATION.VENARI.CS.CMU.EDU

Whoa, hold on here!  One cannot be considered intelligent without
being able to comprehend certain types of mathematics, such as
the concept of number?  Suppose(we won't do this in real life)
that we separate at birth a human child from all others of his
kind.  We're not cruel; he receives adequate care by whatever means
you wish to hypothesize- robots for instance.  I don't think our
young hero will be developing the concept of number, let alone add-
ition, subtraction, etc. anytime in the foreseeable future.  How
about raising 47 babies together, again with no other human contact.
How long will it take the tribe to get past onomonopieatic grunts
and handwaving to a true language with grammar and syntax?  One
generation?  Two?  Twenty?

I am trying to make the point with these examples that ideas, even
basic ones, and intelligence are two separate phenomena, though of
course one must have intelligence to comprehend ideas.  The objection
to cetacean intelligence then seems to be that none of the species
of this order ever demonstrate any ideas that we regard as basic to
the application of intelligence.  One may argue that if whales have a
human order of intelligence, then they should have come up with these
(to us) elementary ideas thousands if not millions of years ago.  So
why haven't they?

My two cents:  what if they have a language at least as expressive as
ours, but it is almost entirely based on signs instead of symbols.
An analogy for how they may communicate amongst themselves would be
to liken it to human beings invested with a video screen in their
chests- instead of crying out "Danger!! Lions sighted in the tall
grass to the north!" we would simply display the pertinent scene.  of
course, since they are more acoustically talented than we are, I am
assigning this function to their echo-location abilities.  Instead of
an arbitrary pattern of sound to designate the "word" "smelt", they
may be able to simply sign for it by replicating the "sound" a smelt
makes.

Given the number of "nouns" in the sea, such a language could be very
complex, and yet be almost entirely devoid of any symbological descrip-
tion of any event.  How would these beasts "think" then?  Well, the
above is just my two cents, but if it is true, and if nobody can come
up with a plausible _testable_ mechanism for this kind of thought, then
the subject of whale intelligence is still moot.


                                            Just Idly Speculating,



                                                   Walker on Earth
Newsgroups: sci.space
From: stgprao@xing.unocal.com (Richard Ottolini)
Subject: Re: Calendar and Zodiak
Originator: stgprao@xing
Organization: Unocal Corporation
Date: Wed, 29 Jul 1992 14:49:55 GMT

In article <25077@scicom.AlphaCDC.COM> wats@scicom.AlphaCDC.COM (Bruce Watson) writes:
>The original question was not answered. Where did the month go? We lost
>12 days when we converted from the Julian to the Gregorian calendar in 
>1752 (cal sep 1752) and two century years 1800 and 1900 did not have
>a leap day. That makes 14 or half a month.

There was never a month lost!!!
Because the year is defined by the cyclic extermal position of the sun
(southmost, winter, for Romans; equal day, spring, for semetic and Persian).
If the year the year was defined by when it crossed a certain point in its
yearly run through the zodiac, then there would be a month lost, but no
current culture defines the year as such.  (The Egyptians defined the year
by the rising of the star Sirius.  Precession would cause the "star year"
to be off from the "sun year" by 20 minutes each year or a month every
2000 years.)
From: gary@ke4zv.uucp (Gary Coffman)
Newsgroups: sci.space
Subject: Re: Antimatter (was propulsion questions)
Date: 26 Jul 92 07:52:59 GMT
Reply-To: gary@ke4zv.UUCP (Gary Coffman)
Organization: Gannett Technologies Group

In article <mikew.712022819@kpc.com> mikew@kpc.com writes:
>jdnicoll@watyew.uwaterloo.ca (James Davis Nicoll) writes:
>>	Given that one can mix the antimatter-reaction mass ratio to get
>>the Vexhaust one wants, the dangers of standing in the vicinity of the
>>exhaust of an antimatter powered ship could be *identical* to that of
>>standing inthe vicinity of a conventional ship.
>Actually there is one piece of information missing here. In a conventional
>rocket most of the exhaust is being used to push more fuel closer to orbit.
>In an antimatter rocket, you have a much higher payload/fuel ratio, so for
>the same payload, there will be much less exhaust.

But lots more gammas. Not a happy thought for the launch pad.

Gary
Newsgroups: sci.space
From: rwallace@unix1.tcd.ie (russell wallace)
Subject: Re: ETs and Radio
Organization: Trinity College, Dublin
Date: Tue, 28 Jul 1992 13:02:36 GMT

Given that for evolution of life to start, a simple living organism must
come together from amino acids etc. by accident; and that for any
complex structure to fall together by accident is extremely improbable;
then it looks pretty much like the odds against life appearing on any
one planet could easily be more than 10^1000 to 1 against, and the
number of planets in the visible universe is only about 10^22.

--
"To summarize the summary of the summary: people are a problem"
Russell Wallace, Trinity College, Dublin
rwallace@unix1.tcd.ie
From: warhaug@dhmolde.no (Geir Warhaug)
Newsgroups: sci.space
Subject: Whales
Date: 22 Jul 92 12:34:03 GMT
Article-I.D.: cs.1992Jul22.123505.217861
Distribution: sci
Organization: [via International Space University]
X-Added: Forwarded by Space Digest
Original-Sender: isu@VACATION.VENARI.CS.CMU.EDU

Thanks to John Robert.

The whale we now hunt, is treathning to wipe out the Bluewhale.
There are more than one side in this case.

Geir
From: me@sys6626.bison.mb.ca (Michael Ellis)
Newsgroups: sci.space
Subject: Re: Antimatter (was propulsion questions) 
Date: Fri, 24 Jul 92 02:36:32 CST
Organization: system 6626 BBS, Winnipeg MB

andy@osea.demon.co.uk (Andrew Haveland-Robinson) writes:

> 
> In article <Brp9H4.3GM@zoo.toronto.edu> henry@zoo.toronto.edu writes:
> 
> >>OK, now to play earths advocate, what kind of danger does releasing all tha
> >>incandescent gas, etc. cause.
> >
> >None whatsoever.  It's hot hydrogen.  The Sun pumps out billions of tons
> >of hot hydrogen every second.
> 
> But that's on the Sun, not in the Earth's atmosphere!
> 
> It's a bit like saying, global thermonuclear war is harmless as the Sun
> releases that much energy every millisecond! :-)
> 
> I wouldn't like to be too near...
> 
> Andy
> ~~~~
> +----------------------------------------------------------------------------
> | Haveland-Robinson Associates        | Email: andy@osea.demon.co.uk         
> | Pine Cottage, Osea Island, Essex    |        ahaveland@cix.compulink.co.uk 
> | CM9 8UH England.  0621-88756        | Also:  081-800 1708  081-802 4502    
> +----------------------------------------------------------------------------

I wouldn't want to be too terribly near to a Shuttle launch either. Or a
smoking gas station attendant for that matter.

No one is talking about dropping an anti-iron connonball onto a city. 
Nor would all this antimatter and matter be combined all at once. 
Payloads of men and equipment can only take so many G's. However, I 
suppose a launchpad explosion would be a particularly nasty thing.

Can anyone say whether an antimatter fueled launch vehicle accident would 
be worse, the same, or perhaps less (no need to lift all that 
heavy fuel) than a conventionally fueled rocket? 


Self-admittedly barely a layperson,

Mike

;--- (Michael Ellis) a user of sys6626, running waffle 1.64
;E-mail: me@sys6626.bison.mb.ca
;system 6626: 63 point west drive, winnipeg manitoba canada R3T 5G8