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Subject: SPACE Digest V13 #738

SPACE Digest                                     Volume 13 : Issue 738

Today's Topics:
               Re: What's HUD?
                Mars or bust!
            Re: Beanstalk analysis reprise
          Re: Grandiosity == Vulnerability?
              Re: SPACE Digest V13 #624
            Re: Fred Vote Thursday
           Bootstrapping with extraterrestrial ice
               Re: Risks of technology

Administrivia:

    Submissions to the SPACE Digest/sci.space should be mailed to
  [e-mail].  Other mail, esp. [un]subscription requests,
  should be sent to [e-mail], or, if urgent, to
             [e-mail]

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

Date: 12 Jun 91 12:37:16 GMT
From: cis.ohio-state.edu!zaphod.mps.ohio-state.edu!rpi!crdgw1!gecrdvm1![e-mail]
Subject: Re: What's HUD?

In article <[e-mail]>, [e-mail] says:
>
>In article <[e-mail]> [e-mail]
>(F026) writes:
>>Not being a US citizen, I have no idea what HUD stands for. Could someone
>>please enlighten me?
>
>Department of "Housing and Urban Development".  These guys can build
>2,000,000 houses on Earth for every one house NASA can build in space.
>Astronaut groupies believe that this one house, about the size of a
>Winnebago, provides a motivation for Congress to move money from HUD
>to NASA.
>
Yes, but out of those 2,000,000 houses (if that many get built after
beaucracy takes its major slice of the pie), how many will be doing
any kind of science?
Also, don't forget the major corruption/scandals that went on in this
department during the Reagon years, and whose clean up is probably the
reason for this budget raise.

PETE


>
>--
>Nick Szabo                              [e-mail]
>"If you understand something the first time you see it, you probably
>knew it already.  The more bewildered you are, the more successful
>the mission was." -- Ed Stone, Voyager space explorer

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

Date: 12 Jun 91 21:47:23 GMT
From: cis.ohio-state.edu!zaphod.mps.ohio-state.edu!rpi!crdgw1!crdos1![e-mail]  (Wm E Davidsen Jr)
Subject: Mars or bust!

This came in this morning, reprinted without comment:

Los Angeles Times

    WASHINGTON - a presidential panel introduced an ambitious but
  controversial program Tuesday to land Americans on Mars by the year
  2014, which includes establishment of a permanent human settlement on
  the moon and the use of nuclear-powered rockets to ferry astronauts and
  supplies on interplanetary missions.

    The long-awaited report comes nearly two years after President Bush
  declared the exploration of Mars as a goal for the U.S. space program,
  and provides the firsl details on how it might be achieved.

    "As Americans, we must ask ourselves what our role will be in man's
  expansion into the solar system: to lead, follow or stand aside," said
  retired Air Force Lt. Gen. Thomas S. Stafford, a forme astronaut and
  chairman of the panel in invoking the lofty rhetoric reminiscent of
  the Apollo space program of the 1960s.

    The 180-page report, calling for a return to the moon by the year
  2005, aroused considerable excitement among space buffs but deep
  concerns among critics who are worried about the huge cost, put at $500
  billion or more by some analysts. The report, issued after 10 months of
  study, did not mention a price tag.

    "It's no accident there are no dollars attached to it," said John E.
  Pike, associate director for space policy at the Federation of American
  sientists. "People would have sticker shock at the price."

    "The report is very long on how from the engineering standpoint. But
  it doesn't make a very persuasive case on why we should be doing it,"
  Pike added.
--
bill davidsen    ([e-mail] -or- uunet!crdgw1!crdos1!davidsen)
        "Most of the VAX instructions are in microcode,
         but halt and no-op are in hardware for efficiency"

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

Date: 13 Jun 91 22:53:44 GMT
From: cis.ohio-state.edu!zaphod.mps.ohio-state.edu!swrinde!elroy.jpl.nasa.gov!blacks![e-mail]  (Robbie)
Subject: Re: Beanstalk analysis reprise

joke:

Gentlemen!  Gentlemen!  All these different ideas!  Debates!
Discussions!  Arguments!  Reading the discourse it seems to
me as though each of you speaks his own separate language!

rf

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

Date: 14 Jun 91 00:56:35 GMT
From: sequent!muncher.sequent.com![e-mail]
Subject: Re: Grandiosity == Vulnerability?

In article <[e-mail]> [e-mail] (Loren Petrich) writes:

[China & Nixon, Columbus & satcoms, plus lots of other fun stuff]

This is a very interesting and thought-provoking article.


>    The Portuguese were the first big explorers, hoping to find
>some alternative route to India and China. So, they painstakingly
>tried going farther and farther around Africa until they made it
>around.

Prince Henry the Navigator hired astronomers and mariners
to work out deep-ocean navigation techniques, and led the first
profitable trading expiditions to Africa in the early and mid 1400's.
Bartholomew Diaz first rounded the African Cape in the 1480's,
and Vasco Da Gama used that route to trade with India.  At a time
when food production and preparation made up the bulk of the GNP,
and refigeration was nonexistant, spices were very important.  Most
spices came from the Orient via a tortuous overland trade route.
The savings from going to over the ocean, avoiding the friction
and politics of the land route, were enormous -- by 1500 the
price of spices in Lisbon was a factor of 5 lower than in Venice
(the port for the overland route), and Portugese merchants were
making heaps of money.  These funds paid for, among other things,
the settlement of Brazil and the voyages of Magellan.


>The Spaniards, not wanting to be outdone, tried a daring move.
>...Ferdinand and Isabella of Spain
>wanted to compete with the Portuguese, and they let this navigator
>have the pick of the local prison population.

The crown did not pay for Columbus' first voyage.  The Santa Maria,
Nina, Pinta, and their crew were financed by Columbus' rich uncle,
who traded with the Portugese in Africa, and by a large Church
organization that owned sizable chunks of the real estate throughout
Europe (sort of a cross between the Moral Majority and Donald Trump,
if you can stomach that. :-)  The larger second voyage was financed
primarily by the crown, after Columbus claimed that he had discovered
an ocean route to India.


>Unlike the case of China, the various
>expeditions of trade, conquest, and colonization had several
>supporters, many of them private individuals or corporations (the
>joint-stock corporation was invented at about this time). It was
>evident that no change of regime could put an end to all the efforts
>to trade with and dominate India and China, or to conquer and settle
>the New World.

The successful projects were self-supporting to the extent
that they could operate within the political whims of the day.
A modern-day example of such an industry is communications
satellites, which NASA except for a few small research projects and
early lauch support have let run their own course.  A side note to
Wales Larrison: the first GEO satcom was conceived and built by
Harold Rosen & Don Williams at Hughes, not NASA.   Hughes and Comsat
had to lobby NASA to even launch the thing, since NASA favored
low-earth orbiting  satellites (sound familiar?)  Hughes, GE, and
Comsat learned their lesson and have largely steered clear of NASA
central planners since then.

Anyway, those are minor nits and comments, you wrote an excellent
article.



--
Nick Szabo                [e-mail]
"If you understand something the first time you see it, you probably
knew it already.  The more bewildered you are, the more successful
the mission was." -- Ed Stone, Voyager space explorer

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

Date:         Wed, 12 Jun 91 20:00:32 EDT
From: Tom McWilliams <[e-mail]>
Subject:      Re: SPACE Digest V13 #624

RE: Asteroid / dino connection

I've seen quite a bit of 'did the asteroid kill the dinosaurs' and related
questions lately.

There's a good article in this July's Sky+Telescope about this.  Includes
not only the evidence for the various possibilities, landing sites, etc,
but also the story of the discovery / discoverers.  Pretty interesting

Tom
Acknowledge-To: <18084TM@MSU>

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

Date: 13 Jun 91 00:19:28 GMT
From: hub.ucsb.edu!ucsbuxa![e-mail]  (Charles Frank Radley)
Subject: Re: Fred Vote Thursday



Design by successive approximation is attractive to reduce
risk, but it is VERY expensive.
    These days as systems get more complex there is greater
reliance on communal computer databases, everybody inputs their
status and the other player view it to see what is going on.
   And simulations, cheaper than flight testing.

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

Date: 13 Jun 91 17:32:47 GMT
From: ogicse!sequent!muncher.sequent.com![e-mail]
Subject: Bootstrapping with extraterrestrial ice

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

>>In the ice fragment
>>business scenario, most of the money needs to be spent not on the
>>capture itself, but on processing the comet material into various
>>products after it has already been delivered into earth orbit,
> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

>Is this the best way?

Yes, because teleoperating at long distances is difficult, and
moving tons of processing equipment over such a large delta-v
takes large amounts of energy and is prohibitively costly.
Processing dominates costs, so the more processing done in Earth
orbit, the cheaper producing the final products will be.  The
economical route is using the native ice itself as reaction mass.
A simple solar-thermal steam engine is more than good enough for
delivering the material with gravity assist.

Once we have bootstrapped ourselves to the point of having large
amounts of reaction mass in Earth orbit, we can afford to start
launching more processing equipment to the asteroids themselves.
We are talking a factor of 1,000 or more drop in the cost of
taking something from LEO to elsewhere in the solar system, as
a result of using extraterrestrial materials.


>It's unsafe, for starters

I covered safety extensively in a recent post.   The scenario
I envision is moving ice in batches of 1,000-10,000 tons each
in gravity assist trajectories.  This is perfectly safe,
since the trajectory is predictable, the error-correcting thrust
available is significant, and the worst-case scenario occurs
naturally every few years without harm.   No nuclear materials are
used.  Moving much larger batches, and/or moving solid rock or
metal materials could present very significant environmental
hazards.  Research needs to be done, with cost/benefit analysis,
and standards established.

Once we have dropped costs by a factor of 1,000, we won't need
to use Earth for gravity assist, so that large, rocky and metallic
materials can be transported safely.  But until the ET materials
fuel bootstrapping occurs, scenarios that do not use Earth are
prohibitively costly.


>Why move the stuff you don't want, when there's no reason not to
>do the processing where you find it?

Nearly all the material can be used, in one way or another.
Heat sinks and shielding, for example, can be made out of
whatever is left over after processing out fuel.   And don't
forget, moving mass in the return trajectory is orders of
magnitude cheaper than moving that mass in the outbound
trajectory, due to the use of ET material as reaction mass.
Once bootstrapping occurs both ways will be cheaper.


--
Nick Szabo                [e-mail]
"If you understand something the first time you see it, you probably
knew it already.  The more bewildered you are, the more successful
the mission was." -- Ed Stone, Voyager space explorer

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

Date: 11 Jun 91 16:04:09 GMT
From: snorkelwacker.mit.edu!usc!wuarchive!emory!wa4mei!ke4zv![e-mail]  (Gary Coffman)
Subject: Re: Risks of technology

In article <[e-mail]> [e-mail] (David Lowe) writes:
>
>>Diverting an asteroid to LEO will cause one positive effect,
>>the Christic Institute will go into orbit. :-)  With all the
>>publicity generated by the Dinosaur Killer, advocating moving an
>>asteroid near Earth will generate mass protests that will make
>>the anti-nukes look positively pro-technology.
>
>I have been enduring all the romance about imminent asteroid
>mining and waiting for someone to discuss safety.  Finally the
>above cheap shot.
>
>The Sununuist attitude that anyone who considers the dangers of
>some high technology project necessarily does so out technophobia
>or ignorance does not stand much scrutiny.  Yes, the effects of
>our bifurcated educational system--which produces astrologist art
>professors and libertarian engineers--can be seen in the anti-
>nuclear power movement.  A closer look, however, finds more than
>a few thoughtful people from the life sciences there.
>
>Suppose for the sake of argument that fabulous sums of money were
>to be lavished on the space mining project and that technological
>breakthroughs were to follow so rapidly one after the other that
>moving an asteroid or comet toward the Earth becomes feasible in
>the lifetime of the youngest person currently on the SPACE
>Digest/sci.space list.  Will the only voices that raise the issue
>of collision belong to the heirs of Jeremy Rifkin?
>
>Of course not.  There is a legitimate problem here and name
>calling is not going to make it go away.

Any system has it's benefits and it's risks. Sometimes the probability
of the risks are so low and the benefits so large that the risks can
reasonably be discounted by informed people. Sometimes a technology
introduces new risks that are better than the risks of the older technology
that it replaces. Sometimes the luddite approach is the most dangerous of
all because having no systems at all is itself a risk.

To properly assess the risks of technology, the skills of the technician who
understands the workings of the system, the skills of the safety engineer who
can pinpoint possible failure mechanisms, the skills of the economist who can
calculate the likely costs and benefits of the system, the skills of the social
scientist who can estimate the social effects of the system, the skills of the
life scientist who can judge the possible health effects, and the skills of
statisticians who understand how to properly weigh and assess the possible
risks and benefits are needed to decide if a given system is a good or bad
choice. Neither Joe Sixpack nor Jane Ecofreak have the necessary skills, or
confidence in those who do, to properly evaluate a system. They are prime
fodder for the Jeremy Rifkins of the world. Even people who possess *one* of
the necessary skills often lack the knowledge to evaluate the entire picture.
They often see a risk or a benefit through the window of their narrow specialty
without evaluating it against the background of other risks or benefits. They
too can be swayed by the Jeremy Rifkins who practice their con jobs with great
skill, playing on people's irrational fears and prejudices.

Whether the risks being discussed are nuclear versus coal or asteroidal
mining versus taking a bath, informed decisions appear to be the exception
rather than the rule. With rocketry having only a 96% success record, and with
the potential for continent wide, or even global, catastrophy caused by an
asteroid strike, I'd be very concerned. If, however, proper redundant systems
are used.  If the approach trajectory minimizes the relative velocities of the
asteroid and Earth. If small scale tests, or insertions into orbits around other
planets have been achieved. And if the economic benefits justify the costs.
Then I'd support the effort.

With nuclear power the track record is clear. We've seen worst case accidents.
We've seen the benefits. Nukes are safer than the systems they replace and
are safer for the average person than taking a bath. They've both caused
deaths and prevented deaths. While the systems aren't perfect, nothing is,
they show a net positive on my balance sheet of risks and benefits. Every
action we take is based on perceived risks and benefits. When you climb
into your car, you are trading the risk of becoming one of the annual
50,000 fatalities against getting to your destination. When you flip the
light switch, you participate in killing coal miners, causing death's
by toxic smoke and acid rain, or possibly exposing someone to radiation
from a nuclear accident. The track record shows the latter possibility
less likely to kill as many people.

Gary

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

End of SPACE Digest V13 #738
*******************