Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V11_3/V11_381.TXT

Internet Message Format | 1991-07-08 | 19KB

Return-path: <[e-mail]>
X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson
Received: from beak.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr11/tm2b/space/[e-mail] (->+dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl) (->ota+space.digests)
          ID </afs/andrew.cmu.edu/usr1/ota/Mailbox/0aGDy5y00VcJIGWk4S>;
          Thu, 10 May 90 01:43:34 -0400 (EDT)
Message-ID: <[e-mail]>
Reply-To: [e-mail]
From: [e-mail]
To: [e-mail]
Date: Thu, 10 May 90 01:42:31 -0400 (EDT)
Subject: SPACE Digest V11 #381

SPACE Digest                                     Volume 11 : Issue 381

Today's Topics:
           Re: Voyager Confirms Relativity
          Re: Contact information for Space Academy?
               Re: why there are no ETs
          Re: Manned mission to Venus (long)
              Re: Fermi Paradox
     Hubble Space Telescope Update - 05/09/90 (Forwarded)
            Request for radio map.
           Re: Voyager Confirms Relativity
      Terraforming Venus (was: Manned mission to Venus)
----------------------------------------------------------------------

Date: 9 May 90 13:09:20 GMT
From: zaphod.mps.ohio-state.edu!samsung!cs.utexas.edu!news-server.csri.toronto.edu!qucdn![e-mail]  (Arnold G. Gill)
Subject: Re: Voyager Confirms Relativity

In article <[e-mail]>, [e-mail] (Gary Wells) says:
>
>Yeah, he _admitted_ that it just changed the question.  But you really didn't
>take a crack at answering the first question: ie, why _might_ it not be so.
>Not saying that it is, just "what's wrong with this idea?".  In my extremely
>limited opinion, it has its points.
     Ah, but it doesn't.  As someone else pointed out already, all the
evidence points to quasars being at far extragalactic distances, for example
the sequence of cD galaxies onto quasars with wisps of a galaxy surrounding
them.  Others pointed out that self-sustaining nuclear reactions don't form in
the balck hole envelopes because the density doesn't get high enough even
though the temperature will eventually.  And at that point, I am not convinced
that much energy will be getting out anyway.  It is a bad mistake to simply
think of black holes as spheres with a very higher escape speed.  The general
relativistic geometry makes a black hole surface a very strange thing indeed.

>We are absolutely guarenteed to be surprised by everything when we finally get
>to see some of this stuff first hand.
     I agree with that, but in a different way.  I will admit that the
postulated idea is interesting.
-------
 -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
|  Arnold Gill                        |                                     |
|  Queen's University at Kingston     |     If I hadn't wanted it heard,    |
|  BITNET   : gilla@qucdn             |       I wouldn't have said it.      |
|  X-400    : [e-mail]  |                                     |
|  INTERNET : [e-mail]  |                                     |
 -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

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

Date: 9 May 90 18:47:00 GMT
From: pacific.mps.ohio-state.edu!zaphod.mps.ohio-state.edu!rpi!rpitsmts![e-mail]   ([e-mail])
Subject: Re: Contact information for Space Academy?



   Steven Winikoff ([e-mail]) writes:

   >After hearing about the adult sessions at the Space Academy in
   >Huntsville, I'd love to go there!  I'd like to write to them to request
   >more information, but I don't have their address.  Does anyone have an
   >address (preferably) or a phone number where they can be reached?

   You can call them at 1-800-63-SPACE.  I don't have the address in
   my office, but I can look it up when I get home.

   Andy Mondore
   [e-mail]
   [e-mail]

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

Date: 9 May 90 23:15:36 GMT
From: swrinde!cs.utexas.edu!news-server.csri.toronto.edu!helios.physics.utoronto.ca!ists!yunexus![e-mail]  (Tony Wallis)
Subject: Re: why there are no ETs

acad!megalon![e-mail] (Paul Baclaski) :
| ... they have created full fledged virtual reality systems and feel no
| need to go exploring space because they have enough fun exploring the
| inner space of their collective minds.            - Paul [e-mail]

One of the themes in "The City and the Stars" - Arthur C. Clarke.
(1950's ?)
--
Tony Wallis  [e-mail]/[e-mail]  (York U. Toronto  Canada)

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

Date: Wed, 9 May 90 23:34:56 EDT
From: John Roberts <[e-mail]>
Disclaimer: Opinions expressed are those of the sender
    and do not reflect NIST policy or agreement.
Subject: Re: Manned mission to Venus (long)


>From: clyde.concordia.ca!mcgill-vision!quiche!calvin![e-mail]  (Mark SOKOLOWSKI)
>Subject: Re: Manned mission to Venus

>>Continuing on Venus surface conditions: the atmosphere at the surface is so
>>thick, walking in it is more akin to wading than walking on dry ground.
>>Also, due to some interesting refractory effects, the horizon appears to curve
>>over your head; even when you are standing on a flat plain, it looks like
>>you are in a bowl.
>>
>This isn't true, as the photos from the Veneras have revealed. In fact, the
>view from the surface is much like on the Earth on an average cloudy day,

The atmosphere at the surface is essentially pure CO2 at 90 atmospheres
pressure and 700-800K (I forgot the exact number). I have asked in previous
postings whether anyone on the list knows the properties of CO2 under these
conditions - apparently nobody does. I doubt it would be as thick as a
liquid, but you might have trouble playing a game of badminton. I don't know
about the refraction, but the Soviet surface pictures were taken through a
fisheye lens, so you couldn't judge them by sight - has there been a formal
analysis of the presence or absence of distortion?

>>All in all, a pretty bleak place. Much less hospitable than the moon;
>>much less easy to colonize than the bottom of our own ocean.
>>
>I don't see why Venus would be so bleak. After all it is brighter on its
>surface than in the cold darkness of the Oceans. Furthermore, artificial
>light, greenhouses with trees and vegetation would make life fairly
>acceptable there. I would even tell you that being there would be more
>enjoyable for me than in some space station lost between the Earth and
>Mars, millions of Km's from any object greater than a grapefruit...

It would be even nicer with a swimming pool, tennis courts, etc., but remember
the price tag. If you could get funding for anything, it would probably be
some tiny utilitarian shelter. (I would roughly guess a cost of $20000-50000
per pound to get payload to Venus. Industrialization might reduce space
infrastructure costs, but you're against that....)

You also seem to assume you would get windows. Of all the places in the
solar system humans might conceivably go in the next 100 years, Venus is the
least likely to have windows. Whatever is chosen for window material must
withstand extreme pressure *plus* high temperature *plus* high temperature
differential, must resist chemical attack, and must serve as an effective
thermal insulator. Even if you had a pressure suit to walk around outside,
the logical design would use a TV camera and a monitor in the helmet rather
than a faceplate. If you have to use a TV camera anyway, you might as well
be in orbit and use a remote camera on the surface. (Does anybody know what
the Soviet landers used for windows?)

>...
>First of all, I'm not talking about a sophisticated suicide. What I want
>to see in such a mission is the breaking of an ultimate frontier. If we
>can land on Venus and STAY THERE ALIVE, then we'll be ready for the entire
>solar system...

As far as I can see, there are two plausible power sources for use on the
surface of Venus - the temperature difference between the lower and upper
atmosphere (by use of balloons and tethers - probably not practical at
this time), and nuclear power (a fission reactor or a big high-temperature
RTG). Unless you can find radioactive material on the planet, you're
dependent on imports. Also consider the Venus pressure suit - you have
three choices - a reactor strapped to your back, a big power cable leading
back to the base (or a big power antenna), or a suit that only works for
a few minutes at a time.
>>
>...In fact, I am afraid about man going
>to Mars, the kind of destruction it can do there. First, we have to solve
>our problems here. Not have so much of them that we will have to export
>all our garbage (cultural and material) in the entire galaxy. That's why
>I think we sould not industrialize space for now (I mean, centuries from
>now). We can go there to conquer, set new frontiers, learn, not colonize
>in an utmost imperialistic way. Will it really matter to have a factory
>on the Moon when there will be 10 billion people down here. I bet the rare
>materials recovered from our satellite will be used to make better weapons
>and extermination means to control our growing social and geopolitical
>problems. I'm a little crude here, but I'm sure that a blind faith
>on salvation from space (and equivalently, a blind faith in the arrival
>of some martians that will help us) is dangerous because it will surely
>let our problem down here grow faster than the actual solutions that
>will be brought by the space-related exotic means.

As several astronauts and others have pointed out, if you wait until you
have solved *all* your problems, you'll never accomplish anything else.
It's pretty much inherent in the system that there will always be some degree
of poverty (note that the standard of poverty regularly changes to meet
current conditions), unemployment, pollution, limited natural resources, etc.
This is largely a result of human physiological and behavioral traits, and
social institutions. These factors come together, for instance, in the
current trend toward massive overpopulation, which in turn makes other
problems worse. I suppose you could change the social structure, outlaw
various religions, change the educational process, etc., but as shown recently
in Eastern Europe, over the long run it's very difficult to change human nature.
(Maybe genetic reprogramming would work... :-)

I'm in favor of preserving natural beauty, but I think one of the major
benefits of nature is the ability of humans to appreciate it and make use
of it. The far side of the moon may be really nifty, but we don't get any
benefit from it sitting here on earth. There's plenty of room out there to
industrialize or colonize and still leave large areas in their natural state.
It's true that space is not a good solution for overpopulation, but it could
serve as a source for energy and natural resources. In addition, people
living in off-earth colonies will *have* to be more conscious of their
environment, because its relative fragility will make it in their best
personal interest to do so. I suspect many of the problems on earth will be
much slower to appear among human populations in space.

Is there any inherent reason that humans should live only on the earth when
they can live elsewhere? Not many people today would argue that we should have
stayed in Africa and left all the other continents empty. And if civilization
should fall apart on earth, would it be wrong to at least give it a chance
to survive elsewhere?

Re: the contention that humans will eventually be able to live unprotected
in the environment of Venus -

It's true that people have survived breathing gases at high pressures, but
I don't know of any evidence that they can do so indefinitely. I believe the
subjects have generally developed severe medical problems after several days
or weeks. (Does anyone know of any counterexamples at very high pressures?)

As far as Venus temperatures are concerned, the human body flat-out doesn't
work at temperatures more than a little above 98.6 F. The brain and other
organs are extremely temperature-sensitive. Enzymes and other chemical
reactions work at the wrong rates, and at higher temperatures proteins start
to break down. It's true that some organisms can survive at higher
temperatures, but they use a different design. To make a human that could
survive at Venus temperatures, you would have to start out by redesigning
several million enzymes and other proteins. There is probably an upper limit
to how high earth-type life can go, and I doubt it's as high as the
temperature on Venus.
                 John Roberts
                 [e-mail]

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

Date: 9 May 90 06:27:27 GMT
From: usc!samsung!munnari.oz.au!bruce![e-mail]  (francis John breen)
Subject: Re: Fermi Paradox


The best explanation i heard of why we arent overrun by aliens is that
the galactic civilizations would have spread over the whole galaxy before
the earth had even formed. After that they have had billions over years
to settle down and get used to not spreading before we came along. and
since then they are no longer bothered about our possible existence.

frank breen - monash uni , comp sci.

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

Date: 9 May 90 16:37:32 GMT
From: zaphod.mps.ohio-state.edu!sdd.hp.com!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Hubble Space Telescope Update - 05/09/90 (Forwarded)

UNITED PRESS INTERNATIONAL -- MAY 9

"Hubble Space Telescope's First Picture Could Come Wednesday"

"The Hubble Space Telescope could take its first picture of the
cosmos as early as Wednesday, a NASA official said."

UPI states that NASA engineers are considering snapping a picture
of a star cluster in the Milky Way to help orient the giant
observatory.  Quoting from orbital verification manager Mike
Harrington, UPI says the picture, previously scheduled to be
taken no earlier than Friday, could be moved up to help assist in
the resolution of a guidance system problem which came up in
tests performed the past few days.

UPI states that NASA has resolved most of the problems which have
affected the Hubble Telescope check-out tests so far but that two
unusual problems involving spacecraft motion were still being
tracked.

                      * * * * * * * *

ASSOCIATED PRESS -- MAY 9

By Harry Rosenthal

"NASA engineers hope to snap the first photograph with the Hubble
Space Telescope's main camera today despite a new setback in
getting the instrument started on its 15-year star-gazing
mission."

AP says the picture would be made late today if engineers decide
to interrupt the telescope's shakedown process, now in its third
week.

Rosenthal says the picture would be of a 3-billion-year-old star
field called Theta Carina, or "Ship's Keel," located in the
southern sky and that the star cluster is 1,260 light years away
and visible with the naked eye in Africa, South America and
Australia.

AP concludes by saying NASA is about a week behind schedule in
the check-out process and that engineers are concentrating their
efforts on resolving two problems associated with spacecraft
motion, one a jittery motion when the telescope is commanded to
roll, and the other a shaking motion when the telescope passes
from shadow into sunlight during its orbit.

 Ron Baalke                       |    [e-mail]
 Jet Propulsion Lab  M/S 301-355  |    [e-mail]
 4800 Oak Grove Dr.               |
 Pasadena, CA 91109               |    Go Lakers!

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

Date: 8 May 90 20:03:16 GMT
From: zephyr.ens.tek.com!tektronix!nosun!qiclab!m2xenix!puddle!p0.f4.n494.z5.fidonet.org![e-mail]  (RKWGRD PUKVM1)
Subject: Request for radio map.

Hi,
I need a radio map of the southern hemisphere for a project on Riometers.
Is there anybody out there that can help me or point me in the right
direction. I would prefer a digitized, computer readable, map. A resolotion
of 1 arc degree would be fine. The frequency is not critical, 30 MHz to
50 MHz would be the ideal.
Please e-mail me directly.
Thanks for reading this note and thanks in advance for any help that I
receive.
Gunther Drevin
[e-mail]



--
uucp: uunet!m2xenix!puddle!5!494!4.0!RKWGRD.PUKVM1
Internet: [e-mail]

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

Date: 9 May 90 00:55:14 GMT
From: zaphod.mps.ohio-state.edu!rpi!uwm.edu!ogicse!zephyr.ens.tek.com!tektronix!percy![e-mail]  (Gary Wells)
Subject: Re: Voyager Confirms Relativity

In article <[e-mail]> [e-mail] (Arnold G. Gill) writes:
>In article <[e-mail]>, [e-mail] (Gordon
>Booman) says:
>>Quasars are just big black holes at normal galactic distances with thin fusing
>>layers.  Mystery solved. :-)  Oh allright, why fusing in a layer, etc. but
>>still, it's a **smaller** mystery now.  At least, closer :-)
>>
>>OK, why not?
>     Then why is a specific quasar always seen at the same value for z?  Why
>should the fusing layer be only found at a specific distance down the gravity
>well?  You end up with a lot more questions than you are answering.

Yeah, he _admitted_ that it just changed the question.  But you really didn't
take a crack at answering the first question: ie, why _might_ it not be so.
Not saying that it is, just "what's wrong with this idea?".  In my extremely
limited opinion, it has its points.

To answer your questions: Once the layer of fusing starts, it stays stationary
over relatively long periods of time, because that's where the conditions are
right for it.  Thus, all observations made over our limited experience, show
the same results.  Why does lava only occur in some spots, or tornados, etc.?
That's where the conditions are right for it.

We are absolutely guarenteed to be surprised by everything when we finally get
to see some of this stuff first hand.

--
--------------------------------------------------------------------------------
Still working on _natural_ intelligence.

gary@percy   (...!tektronix!percy!gary)

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

Date: 8 May 90 22:36:08 GMT
From: zaphod.mps.ohio-state.edu!samsung!umich!ox.com!kitenet![e-mail]  (Russ Cage)
Subject: Terraforming Venus (was: Manned mission to Venus)

There was an interesting article in _Analog_ a while ago,
regarding a method of reducing the atmosphere problem on
Venus.  The proposal was to refine magnesium (and calcium?)
from Mercury's crust, launch the metal towards Venus, and
let it burn in the atmosphere.  Magnesium burns in CO2,
forming magnesium oxide and releasing carbon as soot.

The idea of dropping the atmospheric pressure on Venus
many-fold, combined with filling the upper atmosphere
with a dense black soot which would absorb and re-radiate
most incoming sunlight before it got below the greenhouse,
is appealing.  Water would have to come from elsewhere.
--
              Oversimplification doesn't solve problems, it just
[phone]          changes them into less tractable problems.
Russ Cage, Robust Software Inc.            [e-mail]

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

End of SPACE Digest V11 #381
*******************