HDTenEightyP/NetNews huggingface dataset:
From: wallacen@ColoState.EDU (nathan wallace)
Subject: Re: Making Antimatter
Date: Fri, 08 Jan 1993 19:31:45 GMT
Reply-To: wallacen@beethoven.cs.ColoState.EDU
Organization: Colorado State University -=- Computer Science Dept.

There is yet another interesting book out there, called "Mirror Matter"
by Dr. Robert L. Forward, another far-thinker in this area. He has
worked with DOD and other interested parties on antimatter as a
*practical* energy source right now. He points out that while AM is
useless for bombs due to the fact that instead of "low" energy 
gamma rays like fission and fusion, with AM you get "high" energy
gr which drop back into particles **very** fast and so are hard to
use to transmit energy, thermal shock, etc. This means designing
a practical AM reactor has some interesting problems besides
keeping the AM cool and moving it around.

More interestingly to me, he mentioned that DOD is in the process
of building an accelerator solely for the purpose of generating
AM for use in space projects, both as fuel and for research purposes.
Presumably the "cold" AP mentioned in the recent Sci Am article would
be part of such a system.

So perhaps the antimatter rocket is not as far away as some have
thought....

Reality Check:
We have never actually made antimatter. We have made anti-particles,
but as yet they have never been cold enough to try to get them to
link up into matter. Supposedly this experiment is intended in the
relatively near future; perhaps Bill Higgins could comment on this.

+----------------------------------------------+------------------------+
|                                              |              __        |
|                                              |             / /\       |
|  Nathan F. Wallace                           |      ______/ /_/___    |
|  email: wallacen@beethoven.cs.colostate.edu  |     / ____  ______ \   |
+----------------------------------------------+    / /\__/ /\____|\/|  |
|                                              |   | |\/ / / /     \|/  |
|  Disclaimer: My opinions are my own, and are |   | || / /_/_____      |
|              not those of any other person,  |   | ||/_______  /\     |
|              organization, or supreme being. |   | ||\______/ / /     |
|                                              |   | ||      / / /      |
+----------------------------------------------+    \ \_____/ /_/__/\   |
|  "War is the art of deception."              |     \_____  _______/|  |
|                                 Sun Tzu      |      \___/ /\______|/  |
|                                              |          \_\/          |
|                                              |                        |
+----------------------------------------------+------------------------+



Newsgroups: sci.space,talk.politics.space
From: dietz@cs.rochester.edu (Paul Dietz)
Subject: Re: Justification for the Space Program <long>
Organization: University of Rochester
Distribution: usa, world
Date: Fri, 8 Jan 1993 03:59:25 GMT

In article <1993Jan8.020405.26730@ptdcs2.intel.com> greason@ptdcs2.intel.com (Jeff Greason ~) writes:

> Postulating a (hypothetical) super increase in aluminum extraction
> techniques, common clay (for aluminum) can become a valuable resource.

Hardly "super".  Extraction of alumina from kaolinite is a
demonstrated technology.  It's just not competitive now when bauxites
with > 50% alumina are plentiful.  High grade bauxite reserves should
last ~ 300 years at current consumption rates; somewhat lower grade
bauxite for 1000 years.  Only then would we go after clays or
feldspars.

Note also that the cost of producing alumina is a rather small part of
the cost (both dollar and energy) of producing aluminum.

	Paul F. Dietz
	dietz@cs.rochester.edu

Newsgroups: sci.space,sci.astro,alt.sci.planetary
From: mccall@mksol.dseg.ti.com (fred j mccall 575-3539)
Subject: Re: Moon Dust For Sale
Keywords: U.S. Government funding
Organization: Texas Instruments Inc
Date: Wed, 6 Jan 1993 18:31:39 GMT

In <1993Jan5.211231.5031@aio.jsc.nasa.gov> tes@gothamcity.uucp (Thomas E. Smith [LORAL]) writes:


>I'm just guessing on my figures, but wasn't 500 lbs of moon rock and dust 
>brought back from the moon? And didn't the entire Moon program cost around
>$67 billion? I think that puts the moon dust/rocks at about $134,000,000 a 
>pound! But as Ken says, it ain't fer sale by Nasa.

Of course, the preceding reasoning assumes that the sole function of
the entire Moon program was to produce those rocks as a product.  I
think there was just a BIT more to it than that.  Using the same
logic, one could say that we paid $67 billion to develop Tang.

-- 
"Insisting on perfect safety is for people who don't have the balls to live
 in the real world."   -- Mary Shafer, NASA Ames Dryden
------------------------------------------------------------------------------
Fred.McCall@dseg.ti.com - I don't speak for others and they don't speak for me.
Newsgroups: sci.space
From: clarke@acme.ucf.edu (Thomas Clarke)
Subject: What was NASA Thinking About?
Organization: University of Central Florida
Date: Mon, 4 Jan 1993 13:47:16 GMT

Wanting to refresh my somewhat rusty remembrance of things rocket,
I picked up "Rocket Propulsion Elements" by George Sutton
(1986, 5th ed, John Wiley and sons).
Therein I found the following interesting numbers:
 
Space Shuttle Main Engine	Saturn J-2 Upper Stage
 
Thrust (at alt): 470,000 lbs	230,000 lbs
Specific Imp (alt)   455 sec        426 sec
Dry Weight:         6335 lbs       3454 lbs 
Thrust/Weight:	      74             67
Mixture Ratio:	       6	      5.5
 
Now, I have been led to believe that the SSME is a large
advance over previous engines. The above seems to imply
that with a little work the 6 J-2s could have powered
the shuttle quite nicely.  Perhaps a 6:1 mixture would have
given it the same Isp as SSME - the J-2 thrust and thrust/weight
would have then been 246,000 lbs and 71.5.
 
Also:
 
       Space Shuttle SRB         Saturn F-1 First Stage
 
Thrust(at alt):	 2,372,000	 1,748,000 
Specific Imp:   266 (average)	  265 (grnd) - 305 (alt)   
 
Now, the F-1 does not replace an SRB one for one, but its
no too far off.  Given its good record maybe the F-1 could
have been rerated to 135% throttle to equal the SRB.
 
Hence the question in the title of my post:  What was NASA
thinking about?  Apparently the Saturn engines could have
been used to build the shuttle vehicle.  Why weren't they?
 
A shuttle with 5 or 6 J-2s using 2 uprated F-1s in the recoverable
boosters would have taken advantage of a history of literally
dozens of successful flight firings.  Plus there would
have been a much wider range of abort modes.
 
Happy new year.  Let's hope for more rational future design.

[P.S. I tried posting this from home with a modem last week,
I didn't see it show up, so forrive me if its a duplicate]
--
Thomas Clarke
Institute for Simulation and Training, University of Central FL
12424 Research Parkway, Suite 300, Orlando, FL 32826
(407)658-5030, FAX: (407)658-5059, clarke@acme.ucf.edu
From: matthew@phantom.gatech.edu (Matthew DeLuca)
Newsgroups: sci.space
Subject: Re: foreign partnerships was(Re: How many flights are Orbiters)
Date: 6 Jan 93 00:31:02 GMT
Organization: The Dorsai Grey Captains
NNTP-Posting-Host: oit.gatech.edu

In article <ewright.726276670@convex.convex.com> ewright@convex.com (Edward V. Wright) writes:
>In <1993Jan5.211129.20772@ke4zv.uucp> gary@ke4zv.uucp (Gary Coffman) writes:

>>Interesting street rumor reported on the business report of NBC Sunrise
>>program this morning. Apparently, Boeing is negotiating a partnership
>>with a Japanese and a German firm to underwrite the development of the
>>next generation widebody airliner, reportedly seats 600. 

>This is "news" only to NBC.  Boeing has been negotiating the 777
>project for several years now.  

The 777 is not the plane in question.  If memory serves, the 777 will be a 
twin-engine plane with a seating capacity between that of the 767 and 747, 
whereas the plane Gary mentioned will be signifigantly larger than the 747 
and probably will be a four-engine plane.

According to CNN, Boeing is holding preliminary talks with Deutshce Aerospace,
although the expectation is that eventually the talks will include the 
Airbus consortium.  No Japanese involvement was mentioned, but CNN is hardly 
omniscient.  It was also mentioned that the proposed plane wouldn't fly until
after the turn of the century.
-- 
Matthew DeLuca
Georgia Institute of Technology, Atlanta Georgia, 30332
uucp:	  ...!{decvax,hplabs,ncar,purdue,rutgers}!gatech!prism!matthew
Internet: matthew@phantom.gatech.edu
Newsgroups: sci.space
From: ewright@convex.com (Edward V. Wright)
Subject: Re: DCX tech. info?
Date: Tue, 5 Jan 1993 23:22:03 GMT
Organization: Engineering, CONVEX Computer Corp., Richardson, Tx., USA
X-Disclaimer: This message was written by a user at CONVEX Computer
              Corp. The opinions expressed are those of the user and
              not necessarily those of CONVEX.

In <1icfsjINNlet@rave.larc.nasa.gov> sdd@larc.nasa.gov (Steve Derry) writes:

>How can you have dynamic pressure when you're hovering???

I haven't seen the flight plan, but I believe the high-Q
and hover refer to two different portions of the flight.

>Also, will these flights be pre-programmed onboard, or will they be 
>controlled from the ground?

Don't know.  


Newsgroups: sci.space
From: sysmgr@king.eng.umd.edu (Doug Mohney)
Subject: Re: Man rating again (was: Stupid Shut Cost arguements)
Date: Thu, 07 Jan 93 17:32:54 GMT
Organization: Computer Aided Design Lab, U. of Maryland College Park
Reply-To: sysmgr@king.eng.umd.edu

In article <1993Jan7.025746.2456@iti.org>, aws@iti.org (Allen W. Sherzer) writes:
>In article <1993Jan06.165148.9581@eng.umd.edu> sysmgr@king.eng.umd.edu writes:
>
>>YOU say there's no need to man-rate. The astronaut community and anyone who
>>goes up on it IS going to disagree with you. 
>
>Well after a successful test flight I would go up on it. I think lots of
>others would as well. Anybody with brains enough to read a test report
>and analyze risk wouldn't have any problem. I think most astronauts would
>be included in this list. The ones who don't want to go can quit.

Sure, but you aren't the funding source. Think about it. Was it you or someone
else who suggested that there's a difference between Astronauts and test
pilots? (The latter usually being "expendable.")

>>I realize you'd like to treat people as another type of expendable, but it just
>>ain't so in the Western World. 
>
>Wake up guy! The value of a human life simply isn't infinite. Look at the
>cost model for any large project. Part of it will include the costs associated
>with the people killed on the project. In fact, I'll bet that at least one
>person was killed building each of the 5 shuttle orbiters. People aren't
>expendable but nither do they have infinite value.

>If what you said where actually true then nobody woluld be flying
>Shuttles anyway. So if you want perfect safety, then stay home and
>leave the next frontier to the rest of us.

There's no such thing as perfect safety, and I can see this is degenerating
into a "I'm man enough to die, you wimp" discussion.

I'm sure more people died across the United States in one day than on
Challenger. However, when a good part of national treasure and pride go up with
the vehicle, there IS a difference. 


                    I have talked to Ehud, and lived.
  -- >                  SYSMGR@CADLAB.ENG.UMD.EDU                        < --
Newsgroups: sci.space,sci.aeronautics
From: arromdee@jyusenkyou.cs.jhu.edu (Ken Arromdee)
Subject: Re: Subjective Safety Measure(Re: man-rating)
Followup-To: sci.space,sci.aeronautics
Organization: Johns Hopkins University CS Dept.
Date: Thu, 7 Jan 1993 20:44:34 GMT

In article <1993Jan7.181829.13714@cs.ucf.edu> clarke@acme.ucf.edu (Thomas Clarke) writes:
>The rating of transportation system safety by fatalities per 
>passenger mile always struck me as bogus.  Subjectively, what
>matters is the probability of exit.  That is if I climb in and
>close the door, what are my chances of opening the door and
>climbing out.  By this measure the STS is only about 1 in 50, 
>although it probably isn't as dangerous as, say, a fighter in combat.

In that case, the probability of exit can be made as low as you want, for an
automobile, by stopping along the way.  (The risk of dying on the trip stays
the same, of course.  You just exit more times.)

Unless you mean "for a given length trip, the probability of getting in the
vehicle at the start and coming out at the end, no matter how many stops you
make along the way".  But _this_ measure is of course identical to safety-as-
measured-by-passenger-mile....
--
"On the first day after Christmas my truelove served to me...  Leftover Turkey!
On the second day after Christmas my truelove served to me...  Turkey Casserole
    that she made from Leftover Turkey.
[days 3-4 deleted] ...  Flaming Turkey Wings! ...
   -- Pizza Hut commercial (and M*tlu/A*gic bait)

Ken Arromdee (arromdee@jyusenkyou.cs.jhu.edu, arromdee@jhunix.hcf.jhu.edu)
Newsgroups: sci.space,sci.astro,alt.sci.planetary
From: ewright@convex.com (Edward V. Wright)
Subject: Re: Question:How Long Until Privately Funded Space Colonization
Date: Tue, 5 Jan 1993 21:13:34 GMT
Organization: Engineering, CONVEX Computer Corp., Richardson, Tx., USA
X-Disclaimer: This message was written by a user at CONVEX Computer
              Corp. The opinions expressed are those of the user and
              not necessarily those of CONVEX.

In <3954@key.COM> rburns@key.COM (Randy Burns) writes:

>What are the current estimates of folks in this newsgroup of how long it 
>will be until the world starts to see privately funded space colonization?

Short answer: Soon after the we see privately financed space
industrialization.  Some opinions to the contrary, industry
is not going to spend billions of dollars on space colonies
until there's something for people to *do* there.

And no, a few communications satellites don't count.  To
reiterate, industry is not going to spend billions of dollars 
on space colonies until there's something for *people* to do 
there.

This assumes you mean a for-profit venture.  It's possible
that a charitable organization such as the National Geographic
Society might foot the bill for a colony before industry has a
need for it, but the cost of such a venture would be formidable.

Newsgroups: sci.space
From: gary@ke4zv.uucp (Gary Coffman)
Subject: Re: Stupid Shut Cost arguements (was Re: Terminal Velocity
Reply-To: gary@ke4zv.UUCP (Gary Coffman)
Organization: Destructive Testing Systems
Date: Thu, 7 Jan 1993 08:33:18 GMT

In article <1993Jan5.145312.26531@iti.org> aws@iti.org (Allen W. Sherzer) writes:
>In article <4JAN199322375651@judy.uh.edu> wingo%cspara.decnet@Fedex.Msfc.Nasa.Gov writes:
>
>>Allen I put a question to you. Do you think that if we grounded the Shuttle
>>permanently tomorrow, laid off all personell involved in the Shuttle's overhead
>>and began work on the DC series that the rest of the money would be available 
>>for other uses in space? 
>
>If a worthwhile plan for the money where put forth, we would keep 80% to
>90% of it. At this level money in Congress tends to come top down, not
>bottom up. NASA gets $15B a year because that is how much clout it and its
>supporters have. That money went up under Reagan and bush mostly because
>both where strong supporters of space which gave NASA more clout.

Reagan and Bush couldn't care less about NASA, though Danny thought it
was neat to shoot those big fireworks. But they, and Congressmen,
did care about the money and jobs that NASA represents in their districts.
And they did care about the lobbyists and money that flowed into their
campaigns from aerospace contractors. The bulk of that support comes 
because of Shuttle and Freedom pork. Where's the pork in your schemes?
Which contractors benefit? Which districts get the jobs? Which Comgressmen
are *really* going to be pissed? And do Clinton/Gore really give a damn
if it means money out of their roads and bridges fund? Paving contractors
are the politician's best friend at campaign contribution time.

Gary
-- 
Gary Coffman KE4ZV          |    You make it,     | gatech!wa4mei!ke4zv!gary
Destructive Testing Systems |    we break it.     | uunet!rsiatl!ke4zv!gary
534 Shannon Way             |    Guaranteed!      | emory!kd4nc!ke4zv!gary      
Lawrenceville, GA 30244     |                     | emory!ke4zv!gary@gatech.edu
Newsgroups: sci.space
From: aws@iti.org (Allen W. Sherzer)
Subject: Re: Let's be more specific (was: Stupid Shut Cost arguements)
Organization: Evil Geniuses for a Better Tomorrow
Date: Mon, 4 Jan 1993 21:48:19 GMT

In article <1993Jan4.191452.12294@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes:

>>Which is indeed half the battle. But since you back Shuttle no matter what
>>it costs, I don't see your point.

>I back Shuttle because it's flying *now* and nothing else flying *now*
>has it's capabilities at *any* price. 

I say again, since you back Shuttle no matter what it costs what's your
point?

  Allen

-- 
+---------------------------------------------------------------------------+
| Allen W. Sherzer | "A great man is one who does nothing but leaves        |
|  aws@iti.org     |  nothing undone"                                       |
+----------------------110 DAYS TO FIRST FLIGHT OF DCX----------------------+
Newsgroups: sci.space
Organization: Stanford Linear Accelerator Center
Date: Friday, 8 Jan 1993 10:33:56 PST
From: Jon J Thaler <DOCTORJ@SLACVM.SLAC.STANFORD.EDU>
Newsgroups: sci.space
Subject: Re: *** BUSSARD RAMSCOOP ***

gnb@baby.bby.com.au (Gregory N. Bond) says:

> Current antiproton production is geared towards physics, not
> rocketry.  It is probably possible to create antimatter more
> efficiently if that is the primary goal.

This is probably incorrect, for two reasons:
* Antiproton production and capture  efficiency limits the rate
  at which antiproton storage rings can be filled.  If easily
  obtainable improvements were available, I expect that they
  would have been used already.
* A rocket fuel needs to be cheaply contained.  Storage rings
  are expensive.  Unfortuantely, antiprotons are created moving,
  so they will need to be brought to rest to simplify the containment
  problem.  This is an additional manipulation that the physicists
  don't need to perform.

> However the energy cost is
> huge because conservation tells you that you only create antimatter
> with at least E=mc^2 input energy.
> It will release twice this amount when mixed with ordinary matter.
> Now if we could generate antiprotons with better than 50% efficiency,
> we have an inexhaustible energy supply......

There is no free lunch.  Baryon number is conserved.  This means it costs
the same 2mc^2 (at least) to make an antiproton that one gets back when
it annihilates.
Newsgroups: sci.space
From: henry@zoo.toronto.edu (Henry Spencer)
Subject: Re: RTG's on the Lunar Module
Date: Fri, 8 Jan 1993 18:08:45 GMT
Organization: U of Toronto Zoology

In article <1993Jan8.165057.3965@elroy.jpl.nasa.gov> pjs@euclid.jpl.nasa.gov writes:
>> The radiation hazard from plutonium 238 is insignificant; it's pretty much
>> a pure alpha emitter, and human skin stops alpha particles completely.  (A
>> sheet of paper will do likewise.)  You don't want to eat the stuff...
>
>Somewhere in the recesses of my mind lies a memory of a scientist
>who offered to eat some plutonium if the journalist covering the
>event would eat the same amount of caffeine.  No takers, obviously,
>but does this mean that it would be safe to eat plutonium?

Plutonium 239 would not be very toxic if eaten as the metal, I would think.
(Whereas caffeine in bite-and-chew quantities would be lethal.)  I don't
know as I'd call it "safe", but it might not be certain death.  Inhaling it
into the lungs as fine dust is the quick way to die from plutonium.  The
metal probably wouldn't be absorbed very efficiently when eaten.

Eating any heavy metal isn't exactly recommended, mind you.

>...it should be passed in due course with only the mucus coating
>the alimentary canal getting irradiated.

Most of the body isn't radiation-sensitive enough to be hurt much by
a relatively long-lived isotope like Pu239.  As I recall, what kills you
is getting it into your bone marrow.

Eating Pu238 wouldn't be any worse in terms of radiation, but it would
be extremely painful and possibly fatal because the stuff is *hot*.
Thermally, not radioactively.
-- 
"God willing... we shall return."       | Henry Spencer @ U of Toronto Zoology
       -Gene Cernan, the Moon, Dec 1972 |  henry@zoo.toronto.edu  utzoo!henry
From: roberts@cmr.ncsl.nist.gov (John Roberts)
Newsgroups: sci.space
Subject: Re: Aluminum as rocket fuel?
Date: 4 Jan 93 12:53:04 GMT
Article-I.D.: cs.C0ByIB.9DI.1
Distribution: sci
Organization: National Institute of Standards and Technology formerly National Bureau of Standards
X-Added: Forwarded by Space Digest
Original-Sender: isu@VACATION.VENARI.CS.CMU.EDU


-From: Bruce_Dunn@mindlink.bc.ca (Bruce Dunn)
-Subject: Re: Aluminum as Rocket Fuel?
-Date: 4 Jan 93 00:27:49 GMT
-Organization: MIND LINK! - British Columbia, Canada

-        Sorry for the sloppy wording.  I meant rather "when there is melted
-aluminum in the tank".  I am envisioning a system in which aluminum is
-premelted, possibly in a solar furnace, and poured into an insulated
-tank/valve/combusion chamber unit.  The aluminum will bring the whole system
-up to temperature, and melt any residual aluminum from the last firing.  

Getting an aluminum engine that will work in single-use mode is the first big
step. Making one that can be restarted and reused is a significant further
challenge, which is not necessary to putting aluminum engines in service for
launch from the moon.

-I expect that it won't be too hard to insulate the assembly well enough to keep
-the temperature above the melting point of aluminum for days.  I don't think
-that a heater will be required.  

That's probably correct, though you need to watch out for the possibility
of chemical reactions and leaks when storing molten aluminum for long periods.

-If heating is required for long term
-operation, the logical thing would be to admit a small amount of oxygen into
-the fuel tank to react with the aluminim and heat it.

If you do that, there's a very good chance you'll clog up whatever you're
using to inject the aluminum into the combustion chamber.

John Roberts
roberts@cmr.ncsl.nist.gov
Xref: sparky sci.space:18888 sci.astro:13724 sci.math:17782 sci.misc:1951 sci.physics:22208 sci.physics.fusion:3178 sci.electronics:22157
From: ewright@convex.com (Edward V. Wright)
Newsgroups: sci.space
Subject: Re: Overly "success" oriented program causes failure
Date: 5 Jan 93 17:16:46 GMT
Organization: Engineering, CONVEX Computer Corp., Richardson, Tx., USA
X-Disclaimer: This message was written by a user at CONVEX Computer
              Corp. The opinions expressed are those of the user and
              not necessarily those of CONVEX.

In <C0Cu9q.Bz9@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes:

>What they don't tell you in the textbooks is that although Pert charts
>were indeed invented for Polaris, they *weren't* used to manage it --
>they were used to intimidate assorted Washington kibitzers, keeping
>them at arms length from the people who actually ran the project
>(in the traditional way, using competence and judgement rather than
>Pert charts).

Doesn't surprise me.  From my experience, that seems to be the 
main way they're still used today.
Xref: sparky sci.space:18733 sci.astro:13647 alt.sci.planetary:457