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Subject: SPACE Digest V10 #233

SPACE Digest                                     Volume 10 : Issue 233

Today's Topics:
            Re: Moon Colonies / Ant Tanks?
        Re: Provisional Launch Scheme ESA / ARIANSPACE
              Re: COBE Press Kit (long)
               Request for Soviet info
                   Pegasus
                 Solar power
            Re: Moon Colonies / Ant Tanks?
           Frequently asked SPACE questions
         Re: Atomic weapon/power demographics
----------------------------------------------------------------------

Date: 10 Nov 89 15:58:51 GMT
From: cs.utexas.edu![e-mail]  (Donald A. Varvel)
Subject: Re: Moon Colonies / Ant Tanks?

The comparison of Sasketchewan to the moon has started me thinking.
I lived 15 years in North Dakota.  There are significant differences
between the Northern Plains and the moon.  As was pointed out, the
cost of the infrastructure and its technological sophistication is
quite different.  (There are no polar bears in the plains outside
of zoos, Dan.)  And in North Dakota there's supposed to be a summer.

Consider winter, though.  During blizzards you don't go out.  When
it's -20 with a wind you don't go out unprotected, and I suspect the
time needed to dress in long johns, union suit, wool shirt and trousers,
insulated boots, chopper mits, and snorkel parka is similar to the time
needed to put on a space suit.  (The result has a similar appearance.)
All of this is not needed for just getting into a vehicle and driving
somewhere else, but that would probably be the case on the moon as
well.  Buildings are nearly airtight, which has led to problems with
accumulation of radon and pollutants.  Apartment complexes with large
common areas, such as pool and exercise room, go a long ways toward
dealing with cabin fever.  Shopping malls are connected indoors by
definition, and constitute very substantial enclosed spaces.  In fact,
much of downtown Winnipeg is connected by tunnels and overhead
walkways.

Somebody once asked Arthur C. Clarke, who lives in Sri Lanka, what
it would be like to live in a space colony.  He replied, ``You'll
have to ask my friend Isaac Asimov.  He lives in New York.''  Asimov
was asked why he created something as unattractive as the totally
enclosed lifestyle of the earth civilization in _The Caves of Steel_.
He simply couldn't understand what was unattractive about it.  He
_liked_ the idea of living in steel caves.

People will choose to live on the moon.  I doubt that I will be one
of them, but I have no doubt that there will be many others.

-- Don Varvel ([e-mail])

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

Date: 10 Nov 89 16:41:01 GMT
From: usc!cs.utexas.edu!uwm.edu!mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Provisional Launch Scheme ESA / ARIANSPACE

In article <[e-mail]> [e-mail] ("Rob A. Vingerhoeds / Ghent State University") writes:
>V35     December 1989     Spot 2 (plus six sub-satellites)      Ariane 40
>V36     January  1990     Superbird B/BS2X                      Ariane 44L

I believe these two have now been interchanged.  Spot and friends are in
no hurry, while Arianespace is contractually committed to launch Superbird
*this year*, and there have been enough minor delays to cause some concern
about that.
--
A bit of tolerance is worth a  |     Henry Spencer at U of Toronto Zoology
megabyte of flaming.           | uunet!attcan!utzoo!henry [e-mail]

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

Date: 10 Nov 89 21:08:59 GMT
From: frooz![e-mail]  (Steve Willner)
Subject: Re: COBE Press Kit (long)

From article <[e-mail]>, by [e-mail] (Tom Neff):
> Neither this press kit nor the AvWeek article satisfactorily explains
> a basic question:  Why does COBE need that sun synchronous orbit?
> Why isn't an ordinary equatorial orbit good enough?

The telescope must not be pointed at either the Sun or the Earth, ever.
It also has to cover the whole sky at least once, preferably twice, in a
year.  This is incredibly easy in a Sun-synchronous orbit with the orbit
plane at (nearly) 90 degrees to the Earth-Sun line: just look directly
away from the Earth and at 90 degrees from the Sun at all times, and you
automatically scan the whole sky in six months.  You never have to move
the solar cells at all; you can even use them as part of the Sun shade.
This is exactly what IRAS did, and I thought COBE was using the same orbit.

I don't see any way to do the same thing in a low-inclination orbit
without an incredibly complex guidance system.  (Think about the
pointing constraints when between the Earth and Sun.) Also, eclipses
last almost half of every orbit, which means you need almost double the
solar cell area and big batteries.  Finally, it turns out that the heat
load into the cryogen tank is higher, so it's harder to get as long a
lifetime.

The one thing I wonder about is that the press release mentioned
eclipses; I don't see why there should be any in the IRAS-type orbit.
Maybe COBE is using a slightly different orbit (i.e. not exactly 90
degrees to Earth-Sun line) for some reason.  I didn't see the
information in the press release, although the launch time suggests they
are not far from that orbit.
-------------------------------------------------------------------------
Steve Willner            Phone [phone]         Bitnet:   willner@cfa
60 Garden St.            FTS:      830-7123           UUCP:   willner@cfa
Cambridge, MA 02138 USA                 Internet: [e-mail]

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

Date: 9 Nov 89 22:16:00 GMT
From: texbell!merch!cpe!hal6000![e-mail]
Subject: Request for Soviet info


I'm doing some research on the Soviet space program and Soviet space
policy in general, and I'm looking for some good, current sources of
information.  Apart from tons of AWST articles and other journals, I have
yet to find good books on the current program and policies.  So, I turn
to the net and sci.space for help.  Does anyone have any suggestions as
far as specific books or other info sources about Soviet space policy?
I'm looking for things like international cooperation, commercialization,
military applications, etc..  Any personal views or insight into the
Soviet program would be a great help as well.  Does anybody have any
good ideas?

George Tahu        ...!texbell!letni!hal6000!jack
              or   ...!uunet!swbat!texbell!letni!hal6000!jack

Thanks!

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

Date: 10 Nov 89 16:49:25 GMT
From: cs.utexas.edu!uwm.edu!mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Pegasus

In article <[e-mail]> [e-mail] (ken_scofield) writes:
>  I've seen a few references in recent weeks to the Pegasus project, such as:
>  Unfortunately, I must have come in in the middle of this conversation, as
>  I have scarcely a clue what it is...

Pegasus is a small, privately-funded, air-launched satellite launcher being
developed by Orbital Sciences Corp. and Hercules.  It's a three-stage solid-
fueled rocket (Hercules being a big solid-rocket manufacturer) with a wing
(built by Rutan) and fins on the first stage.  Initially it will be launched
from NASA's B-52, using much the same hardware used to launch the X-15, but
eventually OSC/H will have their own carrier aircraft.  OSC/H seems to have
its act together, with one or two paying customers already (the first launch
is for a DARPA experimental small comsat and a NASA gas-release experiment)
and a lot more interested.  Pegasus development took something like 2.5 years
at a total cost of something like $50M.  First launch was set for late
summer but has slipped to December because of problems with the interface
between Pegasus and B-52.

> ... What is the advantage of air launch?

Mostly, getting up above much of the atmosphere.  There is a further small
benefit from being launched at 500 mph or so.  Side benefits include the
ability to launch to any orbital inclination (just fly the aircraft to a
suitable starting point first) and simplification of safety requirements
(fly out over ocean, avoiding problems with nearby people).
--
A bit of tolerance is worth a  |     Henry Spencer at U of Toronto Zoology
megabyte of flaming.           | uunet!attcan!utzoo!henry [e-mail]

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

Date: 10 Nov 89 15:44:11 GMT
From: sco![e-mail]  (setenv WALRUS green)
Subject: Solar power

I'm hoping that this hasn't already been answered; apologies to
those who have to see yet another article with Galileo in it...

I have heard several people claim that there is indeed enough
light out near Jupiter for it to be practical to use solar panels.
Now, I'm curious: is it true? Or is it that the panels would just
have to be too huge (I'm assuming that size of panels will make
up for lack of ligt; please corerect me if I am wrong). What kind of
power output can you expect at varying distances from the sun?

Oh, as a side note, has anyone asked the various groups that opposed
Galileo why they didn't speak up about any of the other probes or
satellites that have used RTGs?

Thanks in advance.

Joe Di Lellio

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

Date: 10 Nov 89 23:12:39 GMT
From: cs.utexas.edu![e-mail]  (Donald A. Varvel)
Subject: Re: Moon Colonies / Ant Tanks?

In article <[e-mail]> [e-mail] (Tom Neff) writes:
:In article <[e-mail]> [e-mail] (Donald A. Varvel) writes:
:>Somebody once asked Arthur C. Clarke, who lives in Sri Lanka, what
:>it would be like to live in a space colony.  He replied, ``You'll
:>have to ask my friend Isaac Asimov.  He lives in New York.''  Asimov
:>was asked why he created something as unattractive as the totally
:>enclosed lifestyle of the earth civilization in _The Caves of Steel_.
:>He simply couldn't understand what was unattractive about it.  He
:>_liked_ the idea of living in steel caves.
:
:This gets repeated ad nauseam.
:
:A city like New York may look like a steel cave to someone like Clarke,
:but it assuredly is not.  It's a breathing organic entity literally
:filled with life and ecology.  It's quite diverse and TOTALLY
:uncontrolled.  I don't mind if country folk amuse themselves with
:erroneous preconceptions about what cities are like :-) but don't
:try and apply it to this debate as fact.
:
Certainly I recognize the Clarke comment as humorous.  It was hardly
my whole argument.  I thought it fit nicely into that paragraph.  The
Northern Plains in dead of winter can be magically beautiful, and I
didn't mention that either.

The bit about Asimov liking the idea of living in steel caves is from
his autobiography.  It is genuine.  Asimov is from New York.  It has
nothing to do with the ``erroneous preconceptions'' of ``country folk''.
It probably has little to do with New York.  I mentioned it to establish
that there are people who prefer to be indoors nearly all the time.
There are people who spend winters on the Northern Plains, in towns
and small cities, and spend no more than a few minutes at a time, for
weeks on end, unenclosed.  In general, these are far from violent or
antisocial people.  A lot of them play bingo.  Thus, there is another
group that chooses to spend nearly all time indoors for extended periods.
Such people exist.

While I only know about New York City what I read, I have lived much
of my life on the Northern Plains.  There _are_ people such as I describe
above.  There are also people who look forward to winter for such outdoor
activities as skiing and running, and such semi-outdoor activities as
fishing.  The indoor types might adapt quite happily to a lunar colony.
The skiers and runners probably wouldn't.  Unless they put in a walleye
lake, the fishermen probably wouldn't either.

Why would anyone want to live on the moon?  Who knows?  Medical?  Adventure?
Feeling useful?  Science?  Big money bingo?  Just don't assume nobody would
want to spend months on end indoors.  Turning the original argument around,
if you're living in a basement anyway, and enjoying it, why not live in a
basement on the moon?

-- Don Varvel ([e-mail])

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

Date: Fri, 10 Nov 89 04:00:21 PST
From: Eugene 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

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

Date: 10 Nov 89 22:38:27 GMT
From: [e-mail]  (Jon Jacky)
Subject: Re: Atomic weapon/power demographics

> Peter Scott ([e-mail]) writes: ...the number of lives saved
> by the invention of atomic power must be much greater than the number of
> lives taken by atomic weapons (and then he cites many beneficial things
> like radioisotopic medical scans, radiation therapy, etc...)

I work in radiation therapy, so I couldn't resist responding to this one.

There are many beneficial medical (and other) applications of ionizing
radiation, but these have almost nothing to do with, and owe almost nothing
to, the research conducted to produce atomic weapons.  Peter's use of the term
"atomic" is much too loose.  One can categorize applications of nuclear
technology and ionizing radiation in three categories:

    1.) Nuclear weapons
    2.) Nuclear power reactors
    3.) Everything else

The first two depend on nuclear fission, mostly the third does not.
Historically, the first two are more closely coupled because the first nuclear
reactors were built to produce materials to build nuclear bombs.  The third
category is more independent of the other two, and in fact predates them by
a long time.

Ionizing radiation was discovered in the 1890's.  There are two ways you can
get it: from electrical machines (X-ray tubes, linear accelerators,
cyclotrons...) and from radioactive materials, either naturally occuring ones
like radium and uranium or those produced in a reactor, like plutonium.
Diagnostic radiology and radiation therapy using X-ray tubes and radium got
started in the 1890's and were fairly developed by the 1930's.  The first
higher energy accelerator, the cyclotron, was invented in the
1930's.  Fission, which makes nuclear reactors and nuclear weapons possible,
was not discovered until 1938.

Most medical applications of ionizing radiation do not depend on fission.
Diagnostic radiology and radiation therapy primarily use X-ray tubes or
accelerators.  Many medical isotopes are manufactured in accelerators.

It is true, some medical isotopes are manufactured in nuclear reactors.
During the 1950's and 1960's many radiation therapy machines used as radiation
sources cobalt or cesium isotopes manufactured in reactors.  However, these
began to be superceded by linear accelerators in the 1960's.  Linear
accelerators provide many conveniences overe isotopic sources.  Not the least
of which is, the hazards are in general easier to control.  When they are
turned off, they are turned off.  A bit of residual radioactivity remains but
it is not a serious problem.  On the other hand there have been several
serious incidents involving several deaths, due to improper disposal of
isotopic sources from cesium and cobalt machines.  In general, the electric
methods of generating ionizing radiation save you most of the problems of
dealing with troublesomely large quantities of long half-life isotopes.

In summary, nuclear weapons, nuclear power and other applications of ionizing
radiation are largely independent and each must justify itself on its own
terms.

A very good history of these matters can be found in the excellent book by
physicist/historian Spencer Weart, called NUCLEAR FEAR: A HISTORY OF IMAGES.

- Jonathan Jacky
Department of Radiation Oncology
University of Washington
Seattle, WA   98195

[e-mail]

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

End of SPACE Digest V10 #233
*******************