Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V13_2/V13_200.TXT

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Subject: SPACE Digest V13 #200

SPACE Digest                                     Volume 13 : Issue 200

Today's Topics:
             Re: Terraforming, sun shield
               NASA technology choices
              Re: Japan's Space Industry
            Re: Terraforming Venus
             Re: Terraforming, sun shield
          Re: Government vs. Commercial R&D
              Re: "Face" on Mars
             Re: Terraforming, sun shield
  Re: Manoeuvring using rope and anchor(was: Solar Impact Mission.)
        Re: Confusion regarding "Firm Fred Decisions"

Administrivia:

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Date: 24 Feb 91 20:17:57 GMT
From: zaphod.mps.ohio-state.edu!usc!cs.utexas.edu!news-server.csri.toronto.edu!qucdn![e-mail]  (Arnold G. Gill)
Subject: Re: Terraforming, sun shield

In article <[e-mail]>, [e-mail]
(Henry Spencer) says:
>I saw a paper in JBIS proposing impacts by the largest half-dozen asteroids,
>to simultaneously blast off a fair bit of the atmosphere and spin up the
>planet (its rotation is annoyingly slow).  My dim recollection is that the
>blast-off scheme does not, in fact, work as well as the authors proposed.
>It's really hard to get rid of 90atm of gas around an Earth-sized planet.

     Well, then, do what happened to the Earth -- get a bigger planetoid.  The
big Earth impact was supposed to be Mars-sized -- you might even get a moon
for Venus out of it.  If we are terraforming Venus, do we need Mars for
anything anymore?  :-)

 -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
|  Arnold Gill                        |   - If I hadn't wanted it heard,      |
|  Queen's University at Kingston     |         I wouldn't have said it.      |
|  InterNet:  [e-mail]  |   - Astrophysician in training        |
 -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

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

Date: 23 Feb 91 22:13:55 GMT
From: zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!pitt!nss![e-mail]  (Paul Blase)
Subject: NASA technology choices

Philosophical question of the week.

I recently watched 2001: A Space Odessey again.  I rather like the
EVA pods that astronauts used to repair the Discovery.  One of the
recent 'problems' discovered with Space Station Freedom is that the
number of hours of EVA required to repair the station was unacceptably
high.  Thusly, NASA is spending gobs of money on telefactor and robotic
widgetry so that the astronauts don't have to leave the station.  Why
doesn't NASA develop a space pod like those used in 2001?  It would almost
have to be cheaper and less risky (from an R&D point of view).  Any
thoughts?

--- via Silver Xpress V2.26 [NR]
--
Paul Blase - via FidoNet node 1:129/104
UUCP: ...!pitt!nss!Paul.Blase
INTERNET: [e-mail]

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

Date: 24 Feb 91 18:47:00 GMT
From: prism![e-mail]  (Matthew DeLuca)
Subject: Re: Japan's Space Industry

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

>WRONG!!! The Japanese ARE spending serious money on the subject.  They
>intend to MAKE A PROFIT!!!!!!!!! (at our expense).

How do they plan to do it at *our* expense?  If they have sense enough to
go where the profits are, good for them.  Hopefully we'll do the same.

--
Matthew DeLuca
Georgia Institute of Technology      Do not meddle in the affairs of wizards,
Office of Information Technology     for they are subtle, and quick to anger.
Internet: [e-mail]

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

Date: Sun, 24 Feb 91 18:16:38 EST
From: John Roberts <[e-mail]>
Disclaimer: Opinions expressed are those of the sender
    and do not reflect NIST policy or agreement.
Subject: Re: Terraforming Venus



In the discussion on terraforming Venus, an important item should
be taken into account: Venus is one of the very worst places in the
solar system to prepare for large-scale human habitation. (Others
include Jupiter and the sun.) It's interesting to discuss it in a
purely speculative sense, as we might discuss the best way to
populate the earth's core, but with almost any conceivable developments
in technology we could populate Mars, the moon, the asteroids, some of
Jupiter's moons, nearby star systems, and interplanetary space, all with
far less time and trouble than it would take to deal with Venus.

If anybody comes up with a way to easily and precisely manipulate planetary
masses (much larger scale than just running comets into planets), then
I'll be willing to reconsider. :-)

I can dig up some numbers if anybody wants them.
     John Roberts
     [e-mail]

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

Date: 24 Feb 91 03:05:02 GMT
From: timbuk!cs.umn.edu!kksys!orbit!pnet51![e-mail]  (Joshua Duffin)
Subject: Re: Terraforming, sun shield

Just an idea, but as long as we're going to get water from asteroids, how
about if we just send a real big one (err, make that comet I think, asteroids
are more rocky than icy...) into Venus, to kick up a nice cloud of dust to
cool off the planet at the same time as we add water?  Save on energy to
decelerate the comet, too.


UUCP: {amdahl!bungia, crash}!orbit!pnet51!jduffin
ARPA: crash!orbit!pnet51![e-mail]
INET: [e-mail]

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

Date: 25 Feb 91 02:57:25 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] (B. Charles Siegfried) writes:

[I posted patent statistics and analysis of major inventions]

>....Pure research will not result in immediate patents,
>and because of this, private firms are less likely to support
>research in these areas.

I agree.  This topic came about, however, because the argument was
put forth that

(a) important applied science and engineering advances require large projects,
(b) the private industry won't fund these, therefore
(c) the government should undertake these projects.

Analysis of important 20th century inventions showed (a) to be false;
in fact most breakthroughs were produced by a small number of people
with small amounts of money.  Seeing how you feel about the human
genome project, I guess you would agree this is also true for pure
research.  Analysis of patents in general showed that (b) is false; the
overwhelming majority of patents come from private industry.  Therefore,
(c) is surely a bad direction to go for most applied science and
engineering R&D.

Since private industry engages in very little pure research or
exploration, it is desirable for these to be government funded.


>... Although I don't support the government giving
>large grants to stimulate certain areas of research (such as  the
>human genome fiasco), it should support the universities enough to
>provide the large amount of pure research that an growing economy
>needs.

I also agree wholeheartedly with this.  Government support of university
projects is shown by history to be the best way to promote both basic
scientific research and exploration.  The university also has a role
in applied research, as many applied science and engineering
breakthroughs come from corporate/university teams.



--
Nick Szabo            [e-mail]
Think long-term, act now.

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

Date: Sun, 24 Feb 91 17:37:58 EST
From: John Roberts <[e-mail]>
Disclaimer: Opinions expressed are those of the sender
    and do not reflect NIST policy or agreement.
Subject: Re: "Face" on Mars


>From: [e-mail] (Free speech is a sound investment)
>Subject: Background on the Monuments of Mars (was re: Martian mystery?)
>Organization: Digital Equipment Corporation

>If your interested in more background about this subject, you might pick up a
>copy of "The Monuments of Mars" by Richard Hoagland.  I read it last summer and
>found it to be quite interesting.

>  Jim Pflueger                |    [e-mail]
>  DEC Enterprise Integration Services|    !decwrl!thewav.enet!pflueger
>  Costa Mesa, California             |    "Take Kuwait Back! - Go Troops!"

Unfortunately, if you buy such a book, it rewards the author (by royalties)
whether or not his theory makes the slightest sense - so just being sensational
is not valid justification for purchasing a book. (Though with the current
literary climate, one could probably write a book arguing that the "Face"
was carved by Julius Caesar in the year 100000 BC, and make money off it.)

I wonder what those people who wrote "The Jupiter Effect" did with all the
money they made? (I know, they must have shamefacedly bought all the
books back when their theory didn't pan out! ;-)  Anybody have a copy?

Disclaimer: just opinions...
         John Roberts
         [e-mail]

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

Date: 23 Feb 91 20:35:07 GMT
From: borg!vangogh![e-mail]  (Jonathan Leech)
Subject: Re: Terraforming, sun shield


In article <[e-mail]>,
[e-mail] (Chris Hall) writes:
|> We need to put it where the Earth put it's atmosphere; in limestone.
|> That's what the critters are good for. Now the trick would be to get
|> carbonate fixing micro-organisms to settle onto the surface without
|> re-releasing the CO2. At the present surface temperatures of Venus,
|> this might be tricky. Maybe this is where a sun shield could come in
|> handy? Hmmmmmmm

    I dug out my copy of Oberg's _New Earths_ (Stackpole 1981; ISBN
0-8117-1007-6) just now.  The approach he advocates is a little
different from what we've been talking about: rather than removing the
atmosphere mechanically or binding it to rock, he wants to import H2
from Saturn to turn it into water.  Quoting from the summary of the
chapter on Venus:

    "...The most attractive targets in the stifling Venusian
    ``greenhouse effect'' are the trace components which block
    important ``windows'' for the escape of heat (since CO2 by itself
    does not produce a particularly powerful ``greenhouse effect'').
    These are SO2 and H20; both can be attacked either biologically or
    chemically.

    "...The time scale for the surface rocks to cool to habitable
    levels, even under the best conditions, would be measured in
    centuries.

    "...But once the free oxygen is released, the problem is only
    half-solved since there still would be several hundred times too
    much oxygen...Some of that oxygen may be absorbed by surface
    rocks, but without substantial erosion [earlier Oberg claims the
    mass of rock needed is equivalent to a 100 km deep layer covering
    the planet - Jon], the rocks will not be able to handle more than
    a tiny fraction of this oxygen.  A good way to eliminate this
    oxygen would be to import vast qunatities of hydrogen from the
    atmospheres of the outer planets, a tactic which would convert the
    unwanted oxygen into badly needed water"

    End of quote.

    Despite the mass of H2 needed from Saturn being much smaller than
the mass of CO2 to remove from Venus, I suspect it would be a far more
difficult task than removing the Venusian atmosphere - we would have
to actually capture and transport the gas down the gravity well in
some sort of containers.
--
    Jon Leech ([e-mail])    __@/
UNDERWHELMING OFFER OF THE MONTH:
    "Please feel free to skip the payment on this month's statement.
     Normal finance charges will apply." - NCNB VISA

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

Date: 19 Feb 91 17:33:23 GMT
From: zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!pitt!nss![e-mail]  (Paul Blase)
Subject: Re: Manoeuvring using rope and anchor(was: Solar Impact Mission.)


 JJ> Would it be technically possible to extend the idea of dipping
 JJ> into the atmosphere by throwing an anchor out to a planet and
 JJ> swinging around it? What I'm thinking of is, say, a 10Km Kevlar
 JJ> (or Twaron, for us Dutch:-) cable with something like an anchor
 JJ> at the end, have the anchor impact a reasonably sized asteroid
 JJ> (a couple Km diameter, enough orders of magnitude difference in
 JJ> mass that you don't accidentally send the asteroid somewhere
 JJ> you don't want it to be), and release anchor and cable once
 JJ> you're facing the direction you want to go?

A slightly different variation: don't anchor the end of the cable, put
an extendable drag anchor on it and use it for aeromanuvering(?).  That
way you would get a gradual increase in acceleration.

Have you heard of the 'rotovator' proposed several years ago (I forget the
exact source, but I can find it - it is mentioned in the Dr. Forward reports
that I posted summaries of a while back).  The Rotovator is a variation on
the beanstalk; instead of one end of the cable anchored to the ground, both
ends rotate around the center of gravity.  The length of the cable and the
rotation are such that as each end of the cable reaches its closest approach
to the planet (or Luna) it is standing still relative to the ground (for
a few seconds).  The other end, of course, is traveling at a high rate of
speed in the other direction, several hundred kilometers away vertically.
You latch your space pod onto the end of the cable as it is standing still
near the surface and hang on.  The rotation of the cable (similar to that
of a giant wheel rolling around the planet) lifts you off.  When you reach
the other side, at maximum distance from the planet, you let go.  The
advantage of this (as illustrated in Forward's paper, is that it can be built
with available technology, such as Kevlar (the tensile strength required is
less than that required for a beanstalk).

--- via Silver Xpress V2.26 [NR]
--
Paul Blase - via FidoNet node 1:129/104
UUCP: ...!pitt!nss!Paul.Blase
INTERNET: [e-mail]

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

Date: Sun, 24 Feb 91 15:47:36 -0500
From: "Allen W. Sherzer" <[e-mail]>
Subject: Re: Confusion regarding "Firm Fred Decisions"
Newsgroups: sci.space
Cc:

In article <[e-mail]> Charles Radley writes:
   + However, you focus at length on the problems of cutting
   +openings, not of putting airlocks in them.  Anywhere you can
   +bolt a hatch you can bolt an  airlock instead, without any
   +fundamental difficulties.

>   ?? Really.... Would not hold pressure very long !   Airlocks
>involve complex redundant labyrinth seals.    A bolted interface
>is no good.

With appropriate seals it should do. When I scuba dive my life
always depends on the integrity of several bolted interfaces. Ditto for
other undersea applications like subs and underwater dive platforms
for oil drilling. They need to keep integrity for years at a time
and at pressures far greater than in space. You need to pick your
materials differently but I'm sure it is possible.

>  Interesting.  Please tell us how they plan to install an airlock.

I refer you to the External Tank Study published by the Space Studies
Institute (subtle advertizement: these guys do great work; send them lots of
your money). Martin has designed a structure called the Aft Cargo Carrier
(ACC) which connects to the bottom of the ET. It is designed to add
cargo space and one variant of it is an ET based space station. The
ACC has an airlock built into it. The crew can transfer to it via EVA
and have a shirt sleve environment in which to furnish the inside of the
ET.

>Windows would be nice too.

But not a necessity. However, the ACC does have windows.

>Which of them volunteered
>to be the first one to go through the airlock without a suit on ?

If it comes to that, I'll do it.

> Sorry, you just failed the leak test.   Start again.

Assuming that is in fact what happens, no problem. This approach
is so cheap that we just redo the airlock and use the next ET
instead.

>  Nobody has ever installed a kluge fit airlock in orbit, not
>even the Soviets want to be the first to take that risk.

The Soviets have installed kluge airlocks on the ground. They also
do kluge's in space.

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

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

End of SPACE Digest V13 #200
*******************