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Subject: SPACE Digest V11 #382

SPACE Digest                                     Volume 11 : Issue 382

Today's Topics:
             Re: Manned mission to Venus
           Re: Looking for a good telescope
             Re: Manned mission to Venus
                Re: Apollo 12
            Re: Terraforming Venus
                Re: Apollo 12
              Re: SPACE Digest V11 #344
----------------------------------------------------------------------

Subject: Re: Manned mission to Venus
Date: Wed, 9 May 90 13:17:52 MESZ
From: Joseph C. Pistritto <[e-mail]>
Mailer: Elm [revision: 64.9]

Okay, this is a bit long, but for the benefit of the poster, (and others
with similar points of view), I'm going to go thru this one item at a time...

Stuff from Mark S. is with a single carat, stuff from Fraering Philip with 2.

> Subject: Re: Manned mission to Venus
>
> In article <[e-mail]> [e-mail] (Fraering
>  Philip) writes:
[some stuff about the Venusian atmosphere deleted here...]

> >All in all, a pretty bleak place. [Venus] 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...

Ahem...  You seem to be under the misconception that space colonies would
be sterile places, without green things like trees.  Read any of the stuff
Gerard O'Neill has written.  Or Jerry Pournelle's "A Step Farther Out", etc,
where space colonies are discussed.  You need to have green things to produce
a closed (or nearly closed) environmental cycle.  You don't even need
greenhouses, the weather's always fine when you make it yourself...

Besides, you find me a tree that'll live at more than 100 degrees C...

> >
> >All in all, a one-way trip such as you propose would be a very expensive
> >way to die, and for symbolic reasons. Symbolic reasons for exploration
> >have generally been unsuccessful....

> 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...
That must mean you're planning to come back.  And how do you get yourself
off the surface and back to Earth?  Got another Energiya handy?  In reality,
Venus is the 'oddest' of the planets in the inner solar system, and certainly
the hardest to live on.  I bet they'll be colonies on Mercury (ok, only on
a small part of Mercury...) before they have any on Venus.

> >
> >3. Space technology is ***__NOT__*** something that is without promise
> >until we get around to building warp drive several centuries from now.
> >
> Everybody is talking about those asteroids, but some scientists, like
> Carl Sagan, are now speaking against their exploitation.
Then he's cracked.  There are plenty of asteroids out there for the next couple
of centuries anyway.  What happened, did they all suddenly get smaller?  Couple
that with the fact that most asteroids would be entirely usable mineral sources,
without all this useless matter like soil in the way.  Remember, a good fraction
of the metorites picked up on earth have exceedingly high metal content.  There
are over 1000 'Earth grazing' asteroids tracked, from 100m size on up.  This
stuff even comes to us, albeit with a bit of a velocity differential.

> ... but it doesn't mean that we should consider the rest
> of the solar system as a garbage can. 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.
Wrongo... Consider how -BIG- the solar system (even Mars) is.  Considering
how expensive it'll be to move people there, we won't be able to move enough
to do any serious damage to a space that big, even if they took along a few
nukes and set them off...

Besides that, a big part of our problem here is related to raw materials
extraction.  See my previous comment about Earth grazing asteroids...

> ... 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.

Okay, now the bias of the poster is becoming clear...  Imperialism has to
do with colonizing other populated countries by a technologically, (or maybe
just militarily) superior power.  Unless there really are little green men
on Mars, this concept doesn't apply.

> ... Will it really matter to have a factory
> on the Moon when there will be 10 billion people down here.
Yes, most definitely.  Particularly if that factory makes parts for solar
power satellites, which beam down clean, cheap power to the various nations
on earth, rather than burning say coal to produce it.

I'd certainly rather see the Third World building rectennas to receive
space beamed power, than what they do now, which is either do without,
burn up fossil fuels incredibly inefficiently (ever seen a power plant in
India? I have...), or build nuclear plants which are operated unsafely,
or which are diverted to producing nuclear weapons.  Besides, it's probably
even cheaper.

> ... 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.

oh, really?  You mean like there aren't enough 'extermination means' available
already?
This is a serious discussion list.  Please save your half-baked paronoid
political points of view for non-technical lists.

It is a relatively constant theme in human history that any technology is
applied first to warfare.  This isn't something that started recently, and
I'll bet it won't stop anytime soon.  On the other hand, we manage to
muddle through anyway.  Perhaps you haven't noticed that the defeat of
Communism, (a sort of state controlled by repressive means, as you allude
to), has brought about MORE openness, MORE freedom of choice, and eventually
a higher standard of living (coming July 2nd to East Germany).  This was
true of space technology (IRBM, ICBM, etc.) as well, but military uses are
always followed by civilian ones, starting now in space (materials processing
experiments on the Shuttle and especially on Mir).

I really don't understand this viewpoint that sees worldwide destruction in
every textbook...

> Look at the shuttle!!!
> They were promising us ONE FLIGHT PER WEEK!!!!!! Factories, thousand
> of people in space by the 1990's...

Wait a minute.  Who said thousands of people in space.  The flight rate is
indeed less than planned, but that's not the problem you think it is.  There
aren't enough payloads around long term to support 4 times the flight rate
we have now.  Besides, recurring costs would make sure those payloads never
developed, either.  Next generation vehicles may solve that, (like SSX).

> And it costed billions of truly [wasted]
> money, for any unmanned rocket can do the job of the shuttle (I don't care
> about the fact that man is FLEXIBLE, can have INITIATIVE, since the
> reliability needed for a spaceship that can carry men cancels that).

So you'd rather be scattering $100 million comsats all over the ocean floor,
(a la Ariane), or leaving them stranded in orbit (Intelsat VI) then, because
your unreliable boosters screwed up.  I think you might need to have a chat
with the people who write satellite insurance.  They appreciate reliability.
Sure some of the the things the shuttle can do can be duplicated with
unmanned rockets, but we're never going to learn how to live in space (or
anywhere outside the Earth), unless we GO there first!.  Which is why what
the Russians are doing on Mir is so important, and why we need to get off
our asses and get Freedom up.

> When sending men out there, we should be realistic about why we do it!!!
Good idea.  Lets start by having them do useful things then.  Like building
bases on the moon to extract lunar oxygen & helium-3, and to boost materials
for solar powersat construction.

> Sending a manned mission to Venus wouldn't surely be a [waste] of money,
> if we compare the costs with those put up for the B-2 and other military
> curiosities
So, you've obviously figured out how to put a habitat on Venus for $10 billion?
(which is I think more than the B2 cost, but I might be wrong).  Livermore
thinks they can do a mission to Mars, maybe, on that, but everyone else thinks
it a bit low.  So, enlighten us all, will you?  by the way, don't bother
figuring out how to spend the 'peace dividend' on space projects, your
representatives in DC have already got it spent 3 times over on their
favorite social programs, not to mention lining a few more pockets in the S&L
industry...

> ... and because we HAVE TO send [men] on such a mission in order to
> have some interest from the rest of humanity!!!!
alas, a bit of truth here.  But there are plenty of useful things to do to
keep people interested, (besides dying on Venus, that is).
>
> Mark S.
> -------
Mark, you've obviously got a lot of enthusiasm, and that's not necessarily
a bad thing, but a few hints:

1) Stop believing the 'pop-science' crap put out by a lot of people in the
ecological and anti-nuclear/disarmament organizations.  Remember Sturgeon's
law: "90% of everything is crap".

2) When you hear something said, look up the facts yourself.  The taxpayers
put libraries out there so people can use them.  Always ask yourself,
"Does the speaker have a point to prove, an axe to grind".  When yes, become
extremely suspicious.  Most issues, including most space and technology
issues, have a pretty big body of knowledge out there behind them.  get some
of it, read it, and then make up your mind.

3) Stick around here.  We need people with enthusiam.  You can learn a lot
by watching for postings by some of our learned members, (like Henry
Vanderbilt, as an example).  Follow the reasoning in the articles, look
stuff up.  It's even fun.

'nuf said for now.  Best wishes, and don't take any of this personally, it
isn't meant to be.

--
Joseph C. Pistritto (cgch![e-mail], [e-mail])
 Ciba Geigy AG, R1241.1.01, Postfach CH4002, Basel, Switzerland
 Tel: [phone] (work) [phone] (home)   GMT+2hrs!

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

Date: 10 May 90 01:27:34 GMT
From: mcgill-vision!quiche!calvin![e-mail]  (Mark SOKOLOWSKI)
Subject: Re: Looking for a good telescope

In article <[e-mail]> [e-mail] (Sid Shapiro) writes:
>I'm looking for a good telescope for under $1000.  What are the
>possibilities?  Are there any?  Must I go to $2000 or more?  Are there
>any places that I might look for used scopes?
>
>What I want is to see planets, moons of jupiter, rings of saturn, double
>stars, other highlights in the sky.
>
The most important factor is the aperture. The "classical" aperture for
any serious viewing is 20 cm (or 8 inches). I think a good standard is
the Celestron 8 or the Meade series 200x (I've been an astronomy fanatic
a few years ago, and I hope my memory isn't letting me down too much).
You can get them almost anywhere, and the price tag is around $ 1,200.

Mark S.
-------

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

Date: 9 May 90 00:42:20 GMT
From: cs.utexas.edu!uwm.edu!ogicse!zephyr.ens.tek.com!tektronix!percy![e-mail]  (Gary Wells)
Subject: Re: Manned mission to Venus

So why not come up with a really novel way to increase the space available?
Could be something as simple as taking along  a _BIG_ balloon.  Attach that
to a hatch, squirt some "air" (I don't want to get into a big discussion on
the best long term internal atmosphere, thanks) into it, and open the hatch.
It wouldn't  weight much to get it there, could provide quite a volume of
storage, exercise, etc, space.  It might even be partioned to provide "private"
rooms.  (But not sound-proof!)

I realize it would a little more complicated than that, but maybe not too
much so.

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

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

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

Date: 9 May 90 13:48:36 GMT
From: usc!zaphod.mps.ohio-state.edu!rpi!uupsi!rodan![e-mail]  (Allen J Michielsen)
Subject: Re: Apollo 12

In article <[e-mail]> [e-mail] (David Smith) writes:
>In article <[e-mail]> [e-mail] (Bob Mosley III)
>>In article <[e-mail]>, [e-mail] (David Smith) writes:
>>> Can you cite any authority for these statements?
>>...first off, a flame - I've always hated it...
>>"can you site sources?
>By the way, the launch window had to do with the phase of the moon, which
>cycles once a month.  One month was as good as another.

   I have seen 2 videos, brought here by NASA engineers, to go with speaches
they presented. I have sources for neither, except they were professionally
done, labels & credits & copywrite stuff on them & presented by NASA or retired
NASA staff.  The gist of them went as follows,...   While it is true that the
window is basically monthly, that wasn't actually the case.  The computers were
so slow, and the calculations so complex & code so slow, that all the data that
NASA considered required, could not be developed in time to make another window
inside of a time considerably longer than a month.  IF the moons orbit were so
stable that the difference from one month to the next were minor, then consider
the lunar eclipse.  The case if very similar, if the orbit didn't change
slightly from month to month, then there would be a lunar eclipse every month,
else there would be more partial eclipses.  Of most intrest, would be the case
of a month after a total lunar eclipse, why doesn't a partial eclipse follow a
total eclipse if the change is so small.  Check ANY number or sources of lunar
eclipses, dates, & locations.  It isn't that they just appear ALL the time but
are visible at all different places, it is that they are a EVENT, somewhat RARE
AND are visible a wide locations.
   One of these speakers compared the recalcs done now for launches, the hard-
ware, software & methods to those of the apollo or merc period in the
following manner.  The comparison is much like that of a woodshed axe & a
pocket knife.
al

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

Date: 9 May 90 16:35:35 GMT
From: swrinde!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Terraforming Venus

In article <[e-mail]> [e-mail] (Daniel Ake CAROSONE) writes:
>How easy would it be to fission hydrogen from existing matter on the planet?

In a word, hard.  Importing the stuff from elsewhere would be a lot easier.
Tearing heavier nuclei apart to get hydrogen requires vast amounts of
energy -- it's running a high-order fusion reactor backwards! -- and we
don't know how to do it on a useful scale.
--
If OSI is the answer, what is |     Henry Spencer at U of Toronto Zoology
the question?? -Rolf Nordhagen| uunet!attcan!utzoo!henry [e-mail]

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

Date: 9 May 90 17:02:28 GMT
From: hplabsb![e-mail]  (David Smith)
Subject: Re: Apollo 12

Gregory Bond asked why launch windows happened only a few days a month.
They wanted to land with a low sun angle, to bring out the relief at the
landing site.  If they waited too long, the sun would be too high.  I
presume they didn't want to land near sunset, because if landing or lunar
takeoff were delayed, they would end up in the dark.

I will modify my statement that one month was as good as another.
Soon after I posted that, a couple of factors occurred to me which would
make some months better than others, cyclically through the year.  However,
the various times of year used to launch Apollos 10, 11, and 12 would
indicate that the Saturn V had enough margin to cope with this.

The moon's orbit is elliptical, and the major axis does not precess nearly
as fast as the earth-sun line swings around.  When the major axis is
aligned with the earth-sun line, the orbit is more eccentric than when
these lines are crossed.  So the distance to the moon changes somewhat from
one month's window to another.

The moon orbits 5 degrees out of the ecliptic, not over the equator.
(The orbit plane precesses over a 19 year cycle, varying its
inclination to the equator between 18.5 and 28.5 degrees.)  So from
month to month, the moon at constant phase may be farther north or south.
I would think this would be easily accounted for by making the trans-lunar
injection at the appropriate point in the parking orbit.  Putting the
parking orbit inclination at the right orientation to the moon would
affect the time of day of the launch.

Allen J Michielsen gives evidence that the low speed of computation
made it difficult to make the next month's window.  I won't attempt to
argue with his sources, except to repeat that Pete Conrad said that the
wait interval was one month.  The exact figures changed from day to day
within a monthly launch window, and from minute to minute within a daily
launch window, and they coped with that.  Calculations were done on the fly
to get Apollo 13 back home, although it is conceivable that they sacrificed
some accuracy in favor of speed.
--
    David R. Smith, HP Labs
    [e-mail]
    [phone]

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

Date: 9 May 90 23:27:44 GMT
From: eagle![e-mail]  (Jeff Hojnicki)
Subject: Re: SPACE Digest V11 #344

In article <07MAY90.08604257.0023.MUSIC@SDSUMUS> [e-mail] (Andy Edeburn) writes:
>> The West German Space Agency plans to establish a commercial organization
>> to operate and market its payloads on the Columbus space station.
>                                            ^^^^^^^^^^^^^^^^^^^^^^
>        Um, excuse me. What the h*ll this is?

Hopefully, that was a typo. Columbus is the name of the European Space
Agency's attached module for Space Station Freedom.

--
 Jeff Hojnicki   |    [e-mail]         |   // //        // //
 NASA/LeRC       |    [e-mail]     |  =====FREEDOM======
 (216)-433-5393  | - - - - - - - - - - - - - - - - - -| // //  () () // //
 "My opinions are my own, don't blame NASA for them!" |

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

End of SPACE Digest V11 #382
*******************