Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V08/V8_377.TXT

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Date: Mon, 26 Sep 88 19:08:15 PDT
From: Ted Anderson <[e-mail]>
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Subject: SPACE Digest V8 #377

SPACE Digest                                      Volume 8 : Issue 377

Today's Topics:
             Followup on skintight suits
             SETI and sea mammals
              Mutated Berserkers
              Re: "What's New"  09/02/88
              Re: Why no aliens
            Re: Shuttle names--old and new
              Re: Chix in Space
 Alien civilizations, improved grey goo, and biotech civilizations...
        Why nanotechnology is unlikely to be fruitful.
----------------------------------------------------------------------

Date: Fri, 9 Sep 88 17:52:49 EDT
From: John Roberts <[e-mail]>
Subject: Followup on skintight suits


>> * Dale Amon speculates that the inhabitants of a space station might want
>>   to wear skintight suits all the time as a safety precaution. However,
>>   when the suit is worn with ambient atmospheric pressure, the ambient
>>   pressure and the elastic pressure of the suit are *added*. Assuming
>>   something can be done to alleviate breathing difficulties, the problem
>>   remains that the the pressure exerted on the extremities is comparable
>>   to the systolic blood pressure. Since this is the technique used in a
>>   blood pressure test to cut off the flow of blood to a limb entirely,
>>   I consider it very likely that the suit worn indoors would significantly
>>   interfere with the normal functioning of the circulatory system. This
>>   might or might not be a problem for a person "suiting up" to go outside,
>>   but I doubt that it would be a good idea for these suits to be worn all
>>   the time indoors. (What is the "tightness" of the Soviet indoor suits?)

>Wait a minute, if the effect is additive the wearer is subjected to
>two atmospheres.  Isn't this the same horrible pressure that a
>earthbound diver would experience under 33 feet of water?

>Doesn't sound too deadly to me.. if it is not concentrated over
>one spot (like a blood pressure cuff does).

>    Mike Linnig,
>    Texas Instruments

No, the analogy is not valid. For a better analogy, dive to 33 feet and
try to inhale through a garden hose run to the surface. Even better, place
a gasket around your neck, so your body is at two atmospheres pressure,
while your head is at only one atmosphere. A scuba diver underwater is
breathing air at about the same pressure as the surrounding water, and the
pressures inside and outside his body are matched.

The situation you describe would be utterly deadly. At a rough
estimate, the uncompensated pressure on the human trunk would be over
10000 pounds, making breathing impossible. However, if you would
reread the posting, it was stated that the pressure on the
trunk would be about 1/5 atmosphere, with somewhat lower pressure on the
arms and legs. This reduces the problem somewhat. Nevertheless, one posting
on the list has stated that breathing with even a one psi differential
is not really practical. I presume the breathing problem has been solved,
otherwise the suits would not have been usable. My question pertained to
the arms and legs, which in an earthlike atmosphere would be subjected to
860-880mm absolute pressure, with only 760mm compensated by internal
pressure. The overall effect would be a strong tendency for the blood to
stay out of those parts of the body subject to external pressure, and
collect in the parts not subject to external pressure (i.e. the head).

Because of the lag in the mailing list, I will submit two plausible guesses
as to why the test subjects did not suffer from this effect:

 1) Having put on the suits, they quickly got into the vacuum chamber, or
    they quickly put on helmets and breathed air/O2 at 170mm above ambient.

 2) The fabric of the suits would not contract beyond a certain point, so
    the pressure with an external atmosphere was not as great as would be
    thought. After entering the vacuum chamber, the arms and legs would
    naturally swell as they filled with blood from the higher-pressure
    area of the trunk, until the suit had been stretched enough to exert
    the desired pressure.

Further testing and development of the suit seems like a good idea. I just
thought the first 100-200 messages on the subject were somewhat redundant
and failed to cover several potentially important points.

I repeat the following relevant question:
   It has been stated on the net that the Cosmonauts wear elastic clothing,
   possibly to control the distribution of fluids in the body and for other
   reasons. Does anyone have an estimate of the degree of tightness of
   such clothing, expressed in the equivalent of atmospheric pressure?

                                        John Roberts
                                        [e-mail]

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

Date: Fri, 9 Sep 88 18:38:23 EDT
From: John Roberts <[e-mail]>
Subject: SETI and sea mammals

>From: mcvax!ukc!reading!cf-cm!cybaswan![e-mail]  (Steve Hosgood)

>Wouldn't it be sensible to spend some effort looking nearer to home? The seas
>contain several species of (presumed) intelligent life, yet I don't know of
>any sucess at communicating with them short of training dolphins to poke
>messages into computers on giant keyboards! This can hardly be regarded as
>communicating with the creatures can it?

>I would suggest that we have little chance at dealing with ETs until we can
>talk to the other intelligent life on *this* planet. Comments, anyone?

Some marine mammals have large brains, communicate at a high data rate, and
have been trained to perform simple tasks. There is considerable speculation
that they may be very intelligent. However:

 - A large brain does not necessarily imply great intelligence. Marine mammals
   are also sometimes observed doing stupid things.

 - Though the transmission rate may be high, I am not aware of any study
   showing a high rate of transfer of *useful information*. (1000 evenly-
   spaced clicks does not count as 1000 bits of information.) I have heard
   that many species use the same small set of patterns over and over,
   while other species use patterns that change over the course of time.
   Some species may be intelligent while others are not, with size not
   necessarily an identifying factor.

 - Intelligence does not imply the sort of intelligence useful for
   interaction with humans. In general, humans are able to visualize and
   reason abstractly, skilled in communication and eager to communicate,
   naturally curious, willing to work hard for abstract rewards, able
   to think logically (when absolutely necessary :-), technologically
   oriented, etc. Marine mammals fall short in at least some of these
   categories.

The SETI people are looking for aliens who are sufficiently like us for
useful interaction. It is not clear that this will ever be the case with
the marine mammals. If there are dolphin-like animals on other worlds,
there may be no reason for humans to be interested in them as intelligences.

[Does anyone have any information on studies attempting to analyze the
information content of sounds made by sea mammals?]

                                             John Roberts
                                             [e-mail]

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

Date: Fri, 9 Sep 88 19:30:31 EDT
From: John Roberts <[e-mail]>
Subject: Mutated Berserkers

>From: [e-mail]

> ...the Berserkers themselves will the be a technological
>civilization inhabiting the galaxy, and their actions should be visible in
>the sky.

>    Now maybe the Berserkers were originally programmed to be very quiet
>between executions, and carefully designed to prevent mutations in their
>goals.  But they would be present in such large numbers across the galaxy
>that sooner or later a near fatal run-in with a comet, or radiation from a
>stellar flare would modify the program in one in such a way as to remove its
>inhibitions against change.  That event would seed a Darwinian evolution
>of self-reproducing Berserker-derived machines that would acquire the
>survival-oriented goals of normal life.  You can't fool Mother Nature
>forever.

But the universe is not thought to be infinitely large nor infinitely old
(at least by current theory). If you have a universe of only 100 billion
galaxies of 100 billion stars each, with the universe less than 25
billion years old, and the system has been carefully designed so that the
chances that a random change will result in a viable mutation are less than
one in 10**1000, then it is still highly unlikely that the event will have
taken place. Catching a Berserker and reprogramming it would change the odds,
but that does not count as a random change. This is practical from a software
point of view. Proper hardware design might be more difficult.

For further discussion on intelligent machines and highly unlikely events,
including machines (and dragons) that spontaneously come into existence
through the workings of random chance, read "The Cyberiad" by Stanislaw Lem.

                                       John Roberts
                                       [e-mail]

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

Date: 9 Sep 88 12:56:38 GMT
From: [e-mail]  (William H. Jefferys)
Subject: Re: "What's New"  09/02/88

In article <[e-mail]> [e-mail] (Steven Walton) writes:
~
~In the referenced article, the question is raised, "Why does it matter
~that the Hubble Space Telescope is delayed?  Won't the universe wait
~a bit?"
~
~Well, yes, but consider:
~(2) The closer launch gets to the next solar maximum in 1991, the
~    higher the likelihood that HST will have a very premature re-entry
~    unless a second shuttle flight is used to boost it up.

Well, not quite. The earlier it is launched, the more likely that a
reboost would be required. HST's orbit would begin to decay immediately
upon launch, and the later it is launched, the higher it will be at
solar maximum, hence the lower the drag. (I have been present at
presentations where this problem was discussed by the HST project).

From the point of view of reboost, therefore, the new schedule is
more favorable.

Bill Jefferys

--
Glend.    I can call spirits from the vasty deep.
Hot.    Why, so can I, or so can any man; But will they come when you
    do call for them?    --  Henry IV Pt. I, III, i, 53

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

Date: 9 Sep 88 20:20:06 GMT
From: aramis.rutgers.edu!klaatu.rutgers.edu![e-mail]  (J Storrs Hall)
Subject: Re: Why no aliens


    In article <[e-mail]> [e-mail] (Adrian Hurt) writes:
    >Take some sort of propulsion and control/guidance system. And enough fuel to
    >drive it for, say, a month continuously...
    >Could this be done?

    Compute how much fuel it would take to accelerate an asteroid at one gee
    for a month.  Not practical at present.
    --
    ...     Henry Spencer at U of Toronto Zoology

Hmmm.  For a small asteroid a (really raw) envelope-back calculation
says you'd need about half a million metric tons of antimatter (if
you're using equal M-AM reaction, less AM if more matter for reaction
mass).  At a million dollars a microgram, this comes to
$500,000,000,000,000,000, a small fraction of what we spend on
welfare :^) ...

--JoSH

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

Date: 9 Sep 88 07:34:20 GMT
From: portal!cup.portal.com![e-mail]
Subject: Re: Shuttle names--old and new

9/6/88 08:38        [e-mail]:
>"Each team must propose one name for Space Shuttle Orbital Vehicle (OV)
>105. The name must be the name of a sea vessel used in research and
>exploration.
> [...]
>"The name for OV 105 should be a name suitable for an American spacecraft
>and should capture the spirit of America's mission in space.

I don't suppose they'd consider "The Golden Hind" . . .

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

Date: 8 Sep 88 10:30:00 GMT
From: mcvax!ukc!dcl-cs!nott-cs!pyr1.cs.ucl.ac.uk![e-mail]
Subject: Re: Chix in Space


>   It may also offer clues as to how human embryos may one day
>develop in space.

Forgive me if I am wrong, (it's a while since I studied the theory!!),
but are there portions of the human reproductive system that require
some sense of orientation prior to fertilisation?  Something to do with
sperm navigation. (Say, the nano-technologists could really have a
field-day on this one - sperm-launched beacons and egg-detectors!)

>   Colonel Sanders would be proud.

I can just imagine the phone call that arranged the $50000 funding -
" ... listen, I have this theory ....".  I can't help feeling that
Kentucky F.C. could have spent that sort of money in a more
profitable way, like trying to clean up some of their smaller restaurants.
Last time I had some KFC, I had to throw it up cos of someone I found
sharing my meal.  Bad memories.

                ... Bill

************************************************************************
Bill Witts, CS Dept.     *    Nel Mezzo del cammin di nostra vita
UCL, London, Errrp       *    mi ritrovai per una selva oscura
[e-mail]     *    che la diritta via era smarrita.
************************************************************************

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

Date: Sat, 10 Sep 88 16:36:02 CDT
From: "John Kelsey" <[e-mail]>
Subject:  Alien civilizations, improved grey goo, and biotech civilizations...

   About the self-replicating robots someone mentioned before:  Suppose the
robot finds a civilized planet...now, there are 3 options as to what happens...

1.) The robot is more than a match for the civilization, it trashes the planet.

2.) The robot is evenly matched with the planet--it is defeated, but the planet
    is left with only a few survivors.

3.) The civilized planet is of a superior technology than the robots' makers--
    the planet's defences sweep the robot under the rug.

   Now, if #2 happens, the first major engineering feat done by the survivors
is going to be a planetary defence system that includes x-ray laser projectors
the size of the moon, and antiparticle accelerators.  After rebuilding, the
civilization may well send out probes of its own, looking either to kill all
remaining robots, to destroy the creators of the robots, or both.
   After #3, there's a good chance the planet will go after the makers of the
robot, if possible.
   Because of this, I think it'd be seen as a bad idea to launch the robots,
even if you DO hate aliens.  Also, who's to say there haven't been a number of
waves of these robots and robot-chasers already.  God knows, there's been
enough time.

   Also, I came up with a variation on the idea of "Grey Goo" (Nanomachines
whose sole purpose is to use available energy and matter to self-replicate.)
What if, once the goo reaches the center of the planet/asteroid/whatever it's
on, it stores up energy for a couple weeks, then liberates it all in an explo-
sion, blasting globs of grey goo EVERYWHERE.  Nifty, huh?

   Finally, has anybody really thought of the likelihood of a technical
civilization forming?  Not only are there the numerous disasters that can
end a society's advancement (Nuclear, biochemical, or even prolonged conven-
tional war, biotech accident, a fall into tyranny, a plague of some sort (Read
_Galapagos_ by Kurt Vonnegutt), a fall into unreason and superstition, etc.),
but why must a technological society form interested in radio waves or space
travel?  I can imagine, for example, a society whose biotechnology is VERY
advanced, but whose space technology is uninteresting.  They might grow their
own homes, and their clothes, and there might be very simple and effective
birth control, etc., and they would never FEEL population pressure...

   What do you all think?

   -- John Kelsey ([e-mail])

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

Reply-To: mordor!rutgers!pnet01.cts.com!jim
Date: Fri, 9 Sep 88 13:11:11 PDT
From: mordor!rutgers!pnet01.cts.com!jim (Jim Bowery)
To: hplabs!hpcea!hp-sdd!crash!space
Subject: Why nanotechnology is unlikely to be fruitful.

The phase space of possible formations exponentiates with the number of
components.  For the sake of this discussion, lets say these components
are individual atoms of all the reasonably stable elements of the periodic
table.  Nanomachines have astronomically fewer components than do their
macroscopic counterparts.  This is true even when one takes into account
the much greater efficiency with which nanomachines use their components.
(I'm including all "statistical" machines including VLSI circuits and
 mechanisms fabricated using related technology and restricting the
 definition of nanomachines to those mechanisms that use the actual chemical
 bonds individually.)

The likely fruitfulness of a phase space is related to its richness and
the degree to which it has been previously explored.

In the nono-regime, the phase space is exponentially smaller and it has
been very efficiently explored by evolutionary processes (generations on
the order of fractions of seconds to days).  In the macro-regime the phase
space is exponentially larger and it has been very inefficiently explored
by evolutionary processes (generations on the order of years to centuries
with far fewer "organisms" from which to draw mutations).  Note that
I do NOT restrict evolutionary process to biological evolution.  I include
also cultural and technological evolution.

Basically, I'm saying that the number of undiscovered viable novel forms
in the macro-regime is astronomically greater than the number of undiscovered
viable novel forms in the nano-regime because the macro-regime is both
astronomically larger in size and has been explored to a
far lesser extent than the nano-regime.

UUCP: {cbosgd, hplabs!hp-sdd, sdcsvax, nosc}!crash!pnet01!jim
ARPA: crash!pnet01![e-mail]
INET: [e-mail]

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

End of SPACE Digest V8 #377
*******************