Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V13_2/V13_215.TXT

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Subject: SPACE Digest V13 #215

SPACE Digest                                     Volume 13 : Issue 215

Today's Topics:
             Re: Terraforming, sun shield
                  FTS status
          Re: Government vs. Commercial R&D
              Re: Space Profits
             Re: Terraforming, sun shield
             Re: Terraforming, sun shield
          Value per pound vs. cost per pound

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

Date: 26 Feb 91 23:27:16 GMT
From: zephyr.ens.tek.com!tektronix!sequent!crg5![e-mail]  (Nick Szabo)
Subject: Re: Terraforming, sun shield

In article <[e-mail]> [e-mail] (Brian Godfrey) writes:
>In article <[e-mail]> [e-mail] (David Fuller) writes:
>-
>-My opinions are my own.
>
>   No they aren't. You're going to have to learn to share, since I was just
>thinking of posting a similar message. :-)

We Oregon yuppies are doing a _good job_ of plowing over
our farmland so we can build more big yuppie-houses.  In a few
decades, if luck is with us we will have succeeded in ridding this fair
state of its foul ruralities.  How dare you sci.spacer's foil our
schemes by creating _more_ farmland!  :-)


--
Nick Szabo            [e-mail]
Forward in all directions!

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

Date: 27 Feb 91 16:14:28 GMT
From: [e-mail]  (Kevin Dowling)
Subject: FTS status

Keiran Carroll asks about FTS status:

It is difficult to go from a $100M program to zero in a short period
of time - This transition time will probably be used to showcase
as much as possible with a single mission and demonstration.
The current proposal is to move FTS into Code R (Research) group within NASA
and target a single demonstration flight on the shuttle. The demo
would be using the FTS with the task board in the shuttle bay.
Zero-g is required to show much of the control and teleoperation
interactions.

                nivek

aka :    Kevin Dowling        Senior Research Engineer
net :    [e-mail]    Robotics Institute
tel :    [phone]        Carnegie Mellon University
                Pittsburgh, PA 15213

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

Date: 28 Feb 91 07:00:23 GMT
From: zephyr.ens.tek.com!tektronix!sequent!crg5![e-mail]  (Nick Szabo)
Subject: Re: Government vs. Commercial R&D

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] (Nick Szabo) writes:

>>Los Alamos, Sandia, AMROC, OSC, Rocket Research Company, etc. are all
>>experimenting with new launch and propulsion technologies...

>Well, yes and no.

Henry, by any chance have you studied Zen?  :-)


>Amroc et al suffer from not really having the money
>to build experimental prototypes; they are betting the company on their
>nifty new idea working the first time.  George Koopman's original vision
>of Amroc was destroyed by a single pad fire, and the company's long-term
>survival must be considered doubtful.

AMROC's big mistake is not in their technology, but in their business
practices.  With a strategic partner willing to help build a "rocket
clone" to launch existing satellites with the safer AMROC hybrid fuel,
they would stand a reasonable chance of success.


>OSC/Hercules seem to have bet
>successfully on a winged first stage (the only thing that was really novel
>about Pegasus's technology), but so far it's the only success story in
>that crowd.  These technologies would progress further and faster if there
>was research done by people who weren't betting the farm on success.

Here I disagree.  We _do_ have hybrid fuels _and_ air-launched vehicles
that bring the entry level cost of space down by a factor of 4.  We have
them today.  The reason we have them is precisely because of private
investors willing to bet big chunks of their farms.  People and organizations
working with other people's involuntarily proferred farms simply don't
have the same motivation to innovate in commercial or economically viable
ways.  The patent statistics and analysis of major inventions I posted
a few days ago demonstrate this fact.

For more advanced technologies (eg non-chemical-rockets, though even
here Rocket Research Company is at the forefront of electrical propulsion)
and basic science government has a large role in funding the exploration
of as many avenues as possible.


>Los Alamos and Sandia are doing it in small ways, but they don't really
>have any background in launchers.  This cuts both ways, of course; they
>may be better places to do radical new technology.  But they're not
>equipped to do serious work on improving the older stuff.

The government's proper role is precisely the "radical" technology.
Economical, incremental improvements are the role of private industry.


>Even the big government launcher contractors strongly support the idea
>of NASA getting back into propulsion-technology research.

No small coincidence that many of these same contractors are vying for
the rocket research contract.  Just because corporations are calling
for subsidized R&D on their particular products doesn't mean we should
give it to them.


>There is nothing wrong with improving chemical rockets, and indeed it
>badly needs doing.

Good, let it be done by privately funded industry that has the incentive to
do it right.


>Agreed that more diverse ideas also need attention,
>but the idea that you can't possibly lower costs with chemical rockets
>is nonsense.

The idea that per-pound launch costs can be _radically_ lowered by
chemical rockets is nonsense.  Space settlement, and perhaps also
the large-scale industries leading up to it, require such a radical
lowering of launch costs -- by over a factor of 10.


>The real key is to keep Marshall, or whoever, pointed firmly at doing
>technology research rather than trying to build one operational system.

For any non-military, government-funded research, I strongly agree with
this.


>*That* was the big mistake last time.  Note that NASA is, by the looks
>of things, about to repeat it.

Bad news, alas.





--
Nick Szabo            [e-mail]
"What are the _facts_, and to how many decimal places?"  -- RAH

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

Date: Thu, 28 Feb 91 22:22:00 -0500
From: "Allen W. Sherzer" <[e-mail]>
Subject: Re: Space Profits
Newsgroups: sci.space
Cc:

In article <[e-mail]>:

>This is my main criticism of LLNL.  They propose to bring up
>their oxidizer from Earth, they have no plans to use Lunar
>Oxygen, which IMHO is the door to open the High Frontier.

Mr. Radley, efforts to reduce cost and promote infrastructure
development are at the heart of the Great Exploration program.
This is the biggeest difference with NASA and their approach.

Their lunar base mass budget includes 10,000 pounds for soil
rosters to recover oxygen and hydrogen from the lunar soil. They
also include a greenhouse to grow some fo their own food and close
part of the base carbon and nitrogen cycle.

All this is documented in the NRC briefing slides which I thought
you said you have.

> Lunox will make Mars missions much cheaper

Indeed it will. Their current plans are to get ALL the fuel for
the Mars trip from the moon. Their estimates are that it will
take 26 weeks to produce the fuel and transport it to LEO. This
assumes that the composition of the soil at the site is similar
to the soil returned by Apollo (which should be a good bet).

In fact, LLNL's approach to using lunar fuel was one of the things
NASA liked in their assessment of the LLNL plan.

    Allen


--
+-----------------------------------------------------------------------------+
|Allen Sherzer |A MESSAGE FROM THE ANTI-WAR MOVEMENT TO THE PEOPLE OF KUWAIT: |
|[e-mail]   |       "If rape is inevitable, enjoy it!"                     |
+-----------------------------------------------------------------------------+

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

Date: 28 Feb 91 18:06:48 GMT
From: sdd.hp.com!cs.utexas.edu!news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Terraforming, sun shield

In article <[e-mail]> [e-mail] (Heidi Hammel) writes:
>>it's not as if we're going to be destroying existing ecosystems on, say,
>>Venus.  We could hardly leave it in worse shape than it is now.
>                                     ^^^^^
>Spoken from a truly geocentric (humanocentric?) point of view ;-).

Spoken from a biocentric point of view, actually. :-)  Life had considerable
difficulty getting established on the Hawaiian Islands, since they were bare
rock in the middle of a very large ocean.  A few far-travelling species got
things started, though.  Venus is barer rock in the middle of an even larger
ocean.  Only one far-travelling species can get life going there.  If one
believes in Nature's Grand Plan, this is clearly what we were made for.

It might be different if Venus were a major tourist attraction, instead of
being a close approximation to Hell.

>>So which stable ecosystems are we going to be destroying on Venus or Mars?
>
>Hmmm... I seem to remember that one of the experiments for detecting life on
>Mars was tested in Antartica or some such unfriendly place.  It concluded
>that there was no life.  We can't know for sure what may or may not exist.

Clearly we need to investigate a bit more thoroughly before starting
terraforming, but nobody is proposing to get the bulldozers rolling :-)
next week anyway.  Discovery of native life would change the situation
radically.  But if none is found -- as currently seems probable -- there
will come a time when we can say with considerable assurance, "this place
is dead, and will be alive only if we make it so".  My comments assumed
this situation; please don't attack straw men that I didn't provide.

>Just because humanity *can* alter a system doesn't mean it *should* alter a
>system.  *Especially* before the other world is fully explored robotically.

Who is proposing doing it before full exploration?  Not me.

Agreed that "can" is not "should".  But how do we decide?  Is terraforming
automatically unacceptable?  Why?

>What I'm trying to get across is that there is free choice is human
>intervention of natural evolution - whereas plants and insects (in the
>Hawaiian Island example given by Henry originally) are not making active,
>informed decisions to modify the ecosystem. Does *that* answer the question?

Not really; it doesn't explain why you (seem to) think that a carefully-made
informed choice is still somehow evil while blind, unthinking nature is good.
Despite a good many recent botches, we have the potential to do *better* than
more primitive nature, precisely because we can make informed choices.  We
can refuse to intervene; that does not mean we always should.

>>... starting with the greatest ecological
>>disaster in Earth's history:  the evolution of photosynthesis.
>
>And look where it eventually lead us ... purported global warming due in
>large part to humanity's wanton abuse of a non-renewable resource, record
>numbers of species' extinctions...

There's nothing "record" about the current numbers of extinctions.  Nice,
kind old Mother Nature has thrown far more species into the fire than we
ever have.  When I said "greatest ecological disaster", I meant it:  maybe
99% of all species then alive on Earth died of oxygen poisoning immediately
after photosynthesis appeared.  Even the Cretaceous-Tertiary event makes our
unfortunate recent record look like Mother Teresa's.

If we're going to be mere humble servants to Nature, *you* can write the
Environmental Impact Statement for the next Ice Age.  I'd rather simply
prevent it. :-)

Nature is blind.  We are merely shortsighted.  That's an improvement.
--
"But this *is* the simplified version   | Henry Spencer @ U of Toronto Zoology
for the general public."     -S. Harris |  [e-mail]  utzoo!henry

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

Date: 1 Mar 91 02:32:01 GMT
From: usc!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!watserv1!watdragon!watyew![e-mail]  (James Davis Nicoll)
Subject: Re: Terraforming, sun shield

In article <[e-mail]> [e-mail] (Stephen Walton) writes:
>Before we start terraforming, we should remember that no geometric progression
>can continue forever.  A very old Isaac Asimov article pointed out many years
>ago that with a 50-year doubling time for human population, the mass of humans
>would exceed the mass of the earth by about the year 3000.  Put another way,
>if Venus could be opened for human colonization at the time Earth becomes
>"full" (whatever that means), then Venus would become full only 50 years later.

    True, but given that terraforming looks to be time consuming
and expensive, I doubt very much that a runaway population growth
culture could afford to try what is obviously an ineffective solution
to their population problem, nor survive long enough to see the job done.
If you want to room to pack breeders, you don't terraform marginal planets,
you build space slums like the L5 colonies (assuming you have a space program,
and the ability to ship lots of folks into space, which I don't expect that
kind of culture to be able to do). Terraforming looks like the kind of
expensive hobby only a wealthy culture could afford, and currently, our
wealthy culture don't have cancerous population growth rates. I think
this objection to Tforming relies on a strawman; that you Tform to gain
desparately needed new territory.

                            James Nicoll

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

Date: 28 Feb 91 22:50:48 GMT
From: zephyr.ens.tek.com!tektronix!sequent!crg5![e-mail]  (Nick Szabo)
Subject: Value per pound vs. cost per pound

In article <[e-mail]> [e-mail] (Paul Dietz) writes:

>I am unconvinced that existing chemical
>launchers are anywhere near optimal.  The ultimate cost limit, set by
>the cost of fuel, is orders of magnitude less than current cost.

There are several limits besides fuel costs:

* The earth's atmosphere and the aerodynamic constraints it presents
* Environmental costs of large-volume launches: even the Shuttle
  at current launch rates has been cited for possible damage to
  the ozone layer
* Safety and handling costs of handling large structures and large
  amounts of fuel in one gravity and an atmosphere filled with
  oxygen.

The fact is, value per pound has been increasing at a much faster rate
than cost per pound has been decreasing, and this trend is likely to
continue or accelerate.  Research into increasing value per pound is
far more effective, dollar for dollar, than research into decreasing
cost per pound.

At some point you have to say, "it sounded good, but it just didn't
pan out, let's try something else."


>One
>would need a reusable vehicle capable of flying repeatedly with
>minimal labor-intensive overhaul between launches (i.e., not the
>shuttle), but that is not, in principle, impossible.

The above three constraints, and the historical record of chemical
rockets, imply that this is highly improbable, and the pursuit of such
a goal is highly unproductive.  The above goals are nearly indistiguishable
from the original goals of the Shuttle, and such a project would most
likely just be a repeat of the Shuttle.


--
Nick Szabo            [e-mail]
"What are the _facts_, and to how many decimal places?"  -- RAH

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

End of SPACE Digest V13 #215
*******************