Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V11_3/V11_385.TXT

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Subject: SPACE Digest V11 #385

SPACE Digest                                     Volume 11 : Issue 385

Today's Topics:
                 How is HST?
    Re: Terraforming Venus (was: Manned mission to Venus)
    Re: Terraforming Venus (was: Manned mission to Venus)
              Terraforming Earth
            favorite Sagdeev Quote
               Re: why there are no ETs
            Re: Re: Dyson spheres
               Re: why there are no ETs
          'Weather in the VAB?' - a summary
           Frequently asked SPACE questions
----------------------------------------------------------------------

Date: Thu, 10 May 90 10:35:18 SET
From: [e-mail]
Comment: CROSSNET mail via MAILER@CMUCCVMA
Comment: File SPACE MESSG2 A
Subject: How is HST?

There must be great numbers of readers of Space Digest who are
as curious as I about the status of HST. Who can help us sort out
the following three excerpts (which I received all at the same time)???

--------------1--------------
 >Date: 8 May 90 15:00:27 GMT
 >From: frooz!cfa250![e-mail]  (Jonathan McDowell)
 >Subject: Jonathan's Space Report, May 8
 >       ...
 >The Hubble Space Telescope is in its Orbital Verification phase.  A
 >large (6 arcsec/min) oscillation has been found by the Fine Guidance
 >Sensors.  First out-of-focus images are expected this week.

--------------2--------------
 >Date: 8 May 90 20:38:34 GMT
 >From: usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]
 >      (Ron Baalke)
 >Subject: Hubble Space Telescope Update - 05/08/90
 >    ...
 >    ...  At this time the telescope systems are healthy, in
 >proper working order, with only occasional, minor anomalies to
 >report.  A fine guidance sensor star pattern match test was
 >unsuccessful yesterday morning due to the scarcity of higher
 >magnitude stars in the sensors' fields of view.  Operators are not
 >overly concerned since other pattern matches have been successful.

--------------3--------------
 >Date: 9 May 90 05:35:13 GMT
 >From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
 >Subject: NASA Headline News for 05/08/90 (Forwarded)
 >     ...
 >Tonight, Hubble Space Telescope operators will begin preparations
 >leading to the first pictures.  The hardware is operating as it
 >should and calibrations continue to ready the telescope to focus
 >on the first image.  A 36-hour sequence of "bootstrap" commands
 >to position the telescope and lock the fine guidance sensors onto
 >guide and target stars will begin at 6:00 P.M. -- preparing for
 >the first photos possibly on Friday.

The three questions springing to mind are: 1) what happened to the
oscillations?  2) how much commanding is usually necessary per picture?
3) Must there be a bright-ish star near every object to be photographed
and how bright should this be?

Rene Zandbergen
------------------------------------------------------------------
Because these are just my opinions, and only mine, there is no
purpose in telling whom I work for.
------------------------------------------------------------------

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

Date: 10 May 90 12:53:08 GMT
From: rochester![e-mail]  (Paul Dietz)
Subject: Re: Terraforming Venus (was: Manned mission to Venus)

In article <[e-mail]> [e-mail] (Lord Snooty @ The Giant Poisoned Electric Head       ) writes:

>In "A Step Farther Out" by Jerry Pournelle (many years old now) he advocates
>using blue-green algae dropped in massive clouds from above. He assumes that
>these will gradually cause rain to precipitate rainstorms, which will
>slowly descend through the Venusian atmosphere, will eventually hit the
>ground and thereby cool it.
>
>Anyone read this and/or could comment?

This can't work.

Not only is Venus deficient in water (most has escaped to space over
the aeons, it is thought), but it doesn't address the main problem,
which is getting rid of all that CO2.  Algae could convert some of the
CO2 to organics + oxygen.  But if you tried to convert any substantial
fraction this way, the amount of oxygen in the atmosphere would be so
great that the organics would oxidize right back to CO2.

To terraform Venus you have to get rid of that gas, either by removing
it to space or by reacting it with something to form solids.  I
suspect the first option is easiest, using many extremely large fusion
bombs, containing, collectively, billions of tons of fusionable material.

    Paul F. Dietz
    [e-mail]

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

Date: 10 May 90 13:44:24 GMT
From: umigw!mthvax![e-mail]  (Roman)
Subject: Re: Terraforming Venus (was: Manned mission to Venus)

In <[e-mail]> [e-mail] (Russ Cage) writes:

>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.

Great idea!  Now, when will someone figure out as practical a way to
terraform this planet?  (only 1/2 a :-] on that one)



##########################################################################
# [e-mail]  # "Check this out.  You win $5 million from #
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############################## day that big Ed guy gives you the check,  #
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#    in my hand a box        # going to blow up the world in 2 days.     #
#  of chocolate bunnies"     # What do you do?" --H. Chandler (1972-1989)#
##########################################################################

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

Date: 10 May 90 16:09:25 GMT
From: usc!zaphod.mps.ohio-state.edu!uwm.edu!mailrus!news-server.csri.toronto.edu!utgpu!watserv1!maytag!watdragon!watyew![e-mail]  (Brian or James)
Subject: Terraforming Earth


 The major problem with TFing Terra is that there is an
indigenous populations, substes of which will never be able
to reconcile desires for the 'new' terrestrial climate.
If you increase rainfall in North Africa, and that change
turned out to require cooling down the Ukraine below the
temperatures Ukrainians need to farm in, there will be
disagreement [This problem isn't one for unoccupied
worlds, but TFers might run into problems if humans are
allowed to imigate prior to the completon of the
TFing]. If you get rid of the Earth's population, this problem
*does* go away, of course :)
 You'll even get complaints because people in small regions will
not agree what they want [or need] as the ideal climate. In Ontario,
for example, there are about eight million people who react with
surprise and horror every time the mysterious white topsoil
appears [After half a millenium of colonising North America,you'd
think people would realise this is a temperate to artic nation].
Why we are stuck with the lost tribes of Florida I do not know,
but they, no doubt, would want an  absurdly warm climate.
                            JDN

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

Date: 10 May 90 19:45:33 GMT
From: usc!samsung!rex!rouge![e-mail]  (Fraering Philip)
Subject: favorite Sagdeev Quote

"Why must we keep sending space probes to Venus? Were we sentenced to
it?"

Also note, that with Glasnost/Perestroika, and the dethroning of the
marxist theologians from their place of power, the Soviet Union has
put its Venus program on the back burner and sent a space probe to
a possibly water-rich Asteroid orbiting Mars.

Sounds like they believe the asteroids, and Mars, are good places
for a space program to go.

Philip Fraering [e-mail]
"I'm troubled, I'm dissatisfied, and I'm Irish." - Marianne Moore.

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

Date: 10 May 90 15:27:59 GMT
From: manta![e-mail]  (Michael A. Simpkins)
Subject: Re: why there are no ETs

In article <[e-mail]> acad!megalon![e-mail] (Paul Baclaski) writes:
>
>It just occured to me that one of the possible reasons we have not discovered
>extraterrestrial intelligence in the universe is that 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
________________________________________________________________________________________________________________________________________________________________

    Didn't I see you at the Grateful Dead concert last weekend?  :-)



                    -simpkins-
                    Naval Ocean Sytems Center
                    in BEAUTIFUL San Diego
                    (Shamoo is a GIRL!)

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

Date: Thu, 10 May 90 19:30:25 EDT
From: John Roberts <[e-mail]>
Disclaimer: Opinions expressed are those of the sender
    and do not reflect NIST policy or agreement.
Subject: Re: Re: Dyson spheres


Oops! I take back part of what I said yesterday. The radiation being absorbed
and reradiated by the inner surface of the sphere does help - it should
increase the "lift" by 50%.

The pressure from the energy radiated inward and outward cancels out. This
leaves an unbalanced force of the light pressure from the sun plus the energy
being absorbed on the inner surface from the rest of the sphere. While this
second component is equal in power to the solar flux, the outward vector of
its momentum is divided by two because it is not from a "point source".
          John Roberts
          [e-mail]

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

Date: 10 May 90 21:26:01 GMT
From: [e-mail]  (Edward Joseph Bennett)
Subject: Re: why there are no ETs

>>It just occured to me that one of the possible reasons we have not
>>discovered extraterrestrial intelligence in the universe is that 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.

>I'm not sure how serious this was intended to be, but it has the same
>flaw as all the other "they're not seen because they don't want to be"
>arguments: it assumes that ALL civilizations come to the identical
>conclusion.  All it would take is one exception, or one ACTIVE exception
>at any time in the history of the cosmos, to flood the galaxy with
>lifesigns even if 95% of the beings in the galaxy were "SETI dark
>matter" sitting plugged into nine dimensional Nintendo games.

>I still like my explanation.  When you achieve interstellar travel
>or communication, someone comes along and kills you.  Fits the nature
>of the universe, i.e., a real bitch.

I'm not sure how serious yours is either but:

What if we are being observed as an experiment that they wanted minimal
outside interference with. That would explain why we don't see them. If
they are seen they destroy the evidence and they use force to make sure
nobody else comes to see us.

Ed

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

Date: Thu, 10 May 90 18:22:29 +0200
From: [e-mail] (Daniel Fischer)
Subject: 'Weather in the VAB?' - a summary
Cc: [e-mail],
        [e-mail]

So far I've received four replies to my question in <4 May 1990 11:29> whether
there are at times clouds forming inside the Vehicle Assembly Building at KSC.
  {Steve White, Univ. Wisconsin} quoted a colleague who had *seen* it with his
own eyes twice: "Yes, clouds form and if the conditions are good it even rains
a bit."
  {Henry Spencer, Univ. Toronto} quoted two NASA SP books that denied any cloud
formation and call it "baseless folklore". A ventilation system has been
installed to *prevent* any condensation.
  {Thomas Lapp, Newark, DE} told a story a relative had heard in New Orleans'
Superdome: "The ventilation system is an absolute necessity since without it
humidity could rise to the point when clouds would form in the upper part of
the building. So your idea that the VAB has its own weather (and Henry's
comments about the ventilation system) make perfect sense to me."
  {Karl Parks, Maitland, FL} recalls "a tour ride at KSC. The bus stops at the
VAB, but you are not allowed to go in. The tour guide did state that it has
its own weather and that clouds do form."
  So here I stand, with two indirect 'yes', one 'no' from the literature and
the theoretical possibility that it might be so. Isn't there anyone on the
net who actually worked in the VAB and knows *for sure*? I'm really curious!

+- [e-mail] --- Daniel Fischer --- [e-mail] -+
| Max-Planck-Institut f. Radioastronomie, Auf dem Huegel 69, D-5300 Bonn 1,FRG |
+----- Enjoy the Universe - it's the only one you're likely to experience -----+

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

Date: Thu, 10 May 90 04:00:22 -0700
From: Eugene N. Miya <[e-mail]>
Subject: Frequently asked SPACE questions

This list does change.

This is a list of frequently asked questions on SPACE (which goes back
before 1980).  It is in development.  Good summaries will be accepted
in place of the answers given here.  The point of this is to circulate
existing information, and avoid rehashing old answers.  Better to
build on top than start again.  Nothing more depressing than rehashing
old topics for the 100th time.  References are provided because they
give more complete information than any short generalization.

Questions fall into three basic types:
1) Where do I find some information about space?
Try you local public library first.  You do know how to use a library, don't
you?  Can't tell these days.  The net is not a good place to ask for
general information.  Ask individuals if you must.  There are other sources,
use them, too.  The net is a place for open ended discussion.

2) I have an idea which would improve space flight?
Hope you aren't surprised but 9,999 out of 10,000 have usually been
thought of before.  Again, contact a direct individual source for
evaluation.  NASA fields thousands of these each day.

3) Miscellanous queries.  Sorry, have to take them case by case.

Initially, this message will be automatically posted once per month
and hopefully, we can cut it back to quarterly.  In time questions and
good answers will be added (and maybe removed, nah).

1) What happen to Saturn V plans? What about reviving the Saturn V
as a heavy-lift launcher?

Possible but very expensive -- tools, subcontractors, plans, facilities
are gone or converted for the shuttle, and would need rebuilding,
re-testing, or even total redesign.

2) Where can I learn about space computers: shuttle, programming,
core memories?

%J Communications of the ACM
%V 27
%N 9
%D September 1984
%K Special issue on space [shuttle] computers

Other various AIAA and IEEE publications.

Computers in Spaceflight: The NASA Experience
James E.  Tomayko
1988?

3) SETI computation articles?

%A D. K. Cullers
%A Ivan R. Linscott
%A Bernard M. Oliver
%T Signal Processing in SETI
%J Communications of the ACM
%V 28
%N 11
%D November 1984
%P 1151-1163
%K CR Categories and Subject Descriptors: D.4.1 [Operating Systems]:
Process Management - concurrency; I.5.4 [Pattern Recognition]:
Applications - signal processing; J.2 [Phsyical Sciences and Engineering]:
astronomy
General Terms: Design
Additional Key Words and Phrases: digital Fourier transforms,
finite impulse-response filters, interstellar communications,
Search for Extra-terrestrial Intelligence, signal detection,
spectrum analysis

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

End of SPACE Digest V11 #385
*******************