Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT_ZIP/spacedig/V15_1/V15NO186.ZIP/V15NO186

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Date: Fri, 11 Sep 92 05:06:11
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #186
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Space Digest                Fri, 11 Sep 92       Volume 15 : Issue 186

Today's Topics:
         Is NASA really planning to Terraform Mars? (3 msgs)
                  Magellan Science Results Published
          One Small Step for a Space Activist... Vol 3 No 9
                        Pluto Direct/ options
                  Pluto Fast Flyby mission goals...

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Date: 11 Sep 92 04:22:46 GMT
From: David Knapp <[e-mail]>
Subject: Is NASA really planning to Terraform Mars?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:
>In article <[e-mail]>, [e-mail] (David Knapp) writes:
>
>>You mean ignoring any possible consequences of ozone loss and maybe even
>>global warming? Let's even completely ignore increasing risks of nuclear
>>war (from non-NATO develpment) or from nuclear disaster.  We can also ignore
>>steady expansionism of the populace.
>
>Hey, and I bet you were kvetching about the Evil Stockpiles of Nuclear War
>between the United States and the Soviet Union a couple of years ago.

Now why would *I* mind having half of my tax dollars go to a mass of weapons
that could eliminate all life on Earth several times over? I doubt that the
stockpiles were actually evil. Maybe the pentagon invested in exorcists for
them too?

I'll be you knew alllll along that the evil empire wasn't so evil, didn't you.


>It's gone, so there's something else to blow up, er, INFLATE as a "threat"
>to civilization as we know it.

Inflate... Hmmm. Yeah, I guess we blew that nuclear anhiliation thing *way*
out of proportion. They were really just insurance. They would never have
actually used them, I mean, ignoring Nagasaki and Hiroshima, right?


>It's also laughable to look at "global warming" when a single volcanic eruption
>kicks enough enough ash to DROP temperatures despite our many years of
>unregulated environmental engineering, hmm?

You are clearly not well read on the subject. You cannot extract enough
information on that subject from a headline to discuss it intelligently.

>We also don't have enough of a dataset on our world to show what the "real"
>temperature should be. I kid you not. Would you like to average in the ice ages
>and the time before the DinosaurKiller impacted?

But the theory that dinosaurs were killed by a meteor impact is only a theory,
right?

You are correct about global warming. We have no conclusive evidence. On the
other hand if it is truly happening, and we just cannot figure it out, we're
fucked.  Ozone loss, on the other hand, is quite real and quite anthropogenic,
or will you now call me a bunny hugger because I liked ozone the way it was?

I urge you to fight against the chicken littles of the world and stop
wearing sun screen just to prove you're right.

>>Even if you ignore all the globe-threatening issues, *population* growth,
>>which you can *count on*, will still be one of our greatest challenges.  It
>>will keep growing until it simply *can't* and that only happens when world
>>resources, particularly in food stuffs, become steadily taxed. Don't
>>kid yourselves, this is *going* to happen whether you like it or agree with
>>it.
>
>I didn't know we had gone to world goverment. Now, who in the third world is
>going to come and tax US, hmm?

There is effectively a world government, Yes. You misinterpreted the context of
the word 'taxed'.

>Besides, population growth is self-correcting.

Ultimately, yes, but you won't like the way it corrects itself.

> People who have nothing better
>to do start little piss-ant wars and end up killing themselves off.

When the global population saturates, you will not be thinking 'piss ant'
wars anymore. I don't have to try to convince you either because all you
have to do is wait and remember somebody mentioned it to you.


>>Even after you look at the population curve and make some simple extrapolations,
>>keeping in mind things like fossil fuel depletion in the next 50 years,
>>shifting agricultural zones, you do not see this?
>
>Another Club of Rome member. <yawn>

Huh?

>We've been running out of fossil fuels for 100 years. Before that, there was a
>fear of a great shortage of whale oil, due to overhunting.

No, we will *run out* of fossil fuels in less than fifty years.

>Could you tell me what the current demand for whale oil is?

Ah, you're right. Somebody will think of something before there is a problem.
Let's have a beer.

When we do run out of fossil fuels, I'm sure I won't see you shoving to get
an electric car because you were so convinced it wouldn't be an issue. I hope
you like the bus.

>Furthermore, the Club of Ignorance also ignores little things like A)
>Technological Innovation is not static,

Not at all, I'm frankly quite excited about our government launching space
based mirrors and dumping millions of tons of methane into the stratosphere
to correct the ozone hole caused by, er, technology. Well, heck, that was
just one *teensy* error that I'm *certain* can't happen again 'cuz we're
technologically *advanced* now! (makes me feel safe all over)  Probably

we can stuff acid rain (bunny hugger fantasy I'm sure), love canal neighbor-
hoods, and pcbs in penguins in that lot too. CONSPIRACY!!!

> B) Free-market economies stimulate the
>development of more efficient use of resources and substitutes.

Right. Go Bush!  "I love what you do for me!" (and the ecomomy) "But this time
I *promise* not to raise taxes, those damn democrats made me do it"  "Hey,
'merika! Watch me pull a rabbit outta my hat! (not that trick again..) Nuttin
up my sleeve.... PRESTO!"


>>You do not know there is no life on Mars or anywhere else other than Earth.
>>I don't see the relevance of arguing over the label of 'back yard'.  I don't
>>think as a society, or even a planet, we have yet learned how to manage our
>>*own* planet, not even a *little*.  Because of this I don't think we are
>>qualified to begin applying our ignorance to anther planet.
>>
>>Luckily, this will not be an issue for many years.
>
>Naw, you'd better line up now to put Saturn's rings off-limits to Szabo's Ice
>Mining, Inc. And then prepare to go out there and enforce your law, hm?

I'll have some of what you're smoking! ;-)

>                 Support U.N. military force against Serbia

Didn't you just imply there was no world government?

>
>  -- >                  [e-mail]                        < --



No, really, I see what you're saying, until we see that it is a problem,
we should not worry about it. Good strategy.



--
David Knapp                                      University of Colorado, Boulder
Perpetual Student                                   [e-mail]

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

Date: Fri, 11 Sep 1992 04:33:20 GMT
From: David Knapp <[e-mail]>
Subject: Is NASA really planning to Terraform Mars?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Don Roberts) writes:
>In article <[e-mail]>
>[e-mail] (David Knapp) writes:
>
>>You mean ignoring any possible consequences of ozone loss and maybe even
>>global warming? Let's even completely ignore increasing risks of nuclear
>>war (from non-NATO development) or from nuclear disaster.  We can also ignore
>>steady expansionism of the populace.
>
>Yep. Ignore it. Contrary to Chicken Little Opinion, we don't understand
>global warming very well and unless you're planning to move to Antarctica,
>I wouldn't get in a tizzy about the "ozone hole." [see Physics Today, Dec
>'91 for a discussion of the polar stratospheric cloud mechanism for ozone
>depletion by CFC's].

Yep. How did PSCs get there... What are they *made* of... Also see Science
about six issues ago where ozone loss and resulting uv increases are killing
phytoplankton in the antarctic ocean affecting the food chain there. Probably
funded by chicken littles. George must also be a Chicken Little because
he's getting a little sweaty there and rushing the CFC ban date. I never saw
him as a bunny hugger before.

I'm keeping quite abreast of CFC ozone depletion as much of that research
is being done here.

>As for the "increasing risk of nuclear war" due to nuclear proliferation,
>Nonsense. The threat of all-out thermonuclear war *is gone* (huzzah!).

Hmm, might want to inform Hussein about that. You must have personally inspected
every third world country for nuclear weapons research. How does Israel feel
today... Turkey? China!

> The
>threat of despotic countries seeking to develop nuclear weapons *is* real,
>and requires more stringent efforts in UN inspections, non-proliferation
>research, and development of both a defense against limited strikes and
>the abililty to disable a "terrorist bomb."  Complaining about the "global
>threat" won't make it go away.

Nope, neither will ignoring it.

I suprised to hear that you think the present state of apparent nuclear threat
is permanent.


>>Even if you ignore all the globe-threatening issues, *population* growth,
>>which you can *count on*, will still be one of our greatest challenges.  It
>>will keep growing until it simply *can't* and that only happens when world
>>resources, particularly in food stuffs, become steadily taxed. Don't
>>kid yourselves, this is *going* to happen whether you like it or agree with
>>it.
>
>Haven't we had about enough of this in the last 200 years?? Ever since
>Malthus first came up with the idea, we've been in Imminent Peril of
>choking the planet with people. Fortunately, there have been enough people (!)
>cleverer than ol' Tom that we've managed well enough. Try telling the
>people in Singapore, Japan, or Taiwan that high population densities
>guarantee abject poverty and starvation. Ever stop to think there might be
>more to it than that?

Hmm. You're right. I feel better now. What's another 5 billion people anyway.
I'm sure everything will be allllll right.

>
>--
> Dr. Donald W. Roberts
>   University of California                                      Physicist
>   Lawrence Livermore National Laboratory         Recreational Bodybuilder
>   [e-mail]                                           Renaissance Dude
                            ^^^^^^^^^^^^^^^^^^

Whoa!




--
David Knapp                                      University of Colorado, Boulder
Perpetual Student                                   [e-mail]

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

Date: 11 Sep 92 06:47:53 GMT
From: Don Roberts <[e-mail]>
Subject: Is NASA really planning to Terraform Mars?
Newsgroups: sci.space

In article <[e-mail]>
[e-mail] (David Knapp) writes:
>[e-mail] (Don Roberts) writes:
>>[e-mail] (David Knapp) writes:

>>unless you're planning to move to Antarctica,
>>I wouldn't get in a tizzy about the "ozone hole." [see Physics Today, Dec
>>'91 for a discussion of the polar stratospheric cloud mechanism for ozone
>>depletion by CFC's].

>Yep. How did PSCs get there... What are they *made* of...

According to the article I mentioned, the PSC's are nitric acid (type I)
or water ice (type II). They serve as nucleation sites for the
ozone-depleting catalysis involving reactive chlorine. Since the ozone
depletion seems to be intimately tied to physical processes that occur
only at the poles, it's not clear (to me) that CFC's can deplete the ozone
anyplace else. Ozone's a very unstable molecule, created and destroyed
locally in the upper stratosphere. So what happens at the South Pole
really doesn't affect us. That was my previous point.

>Also see Science
>about six issues ago where ozone loss and resulting uv increases are killing
>phytoplankton in the antarctic ocean affecting the food chain there. Probably
>funded by chicken littles. George must also be a Chicken Little because
>he's getting a little sweaty there and rushing the CFC ban date. I never saw
>him as a bunny hugger before.

Ah, a rebuttal which cites George Bush as an expert on CFC chemistry. How can
I defend myself against *that*?!...:)

>>As for the "increasing risk of nuclear war" due to nuclear proliferation,
>>Nonsense. The threat of all-out thermonuclear war *is gone* (huzzah!).

>Hmm, might want to inform Hussein about that. You must have personally
>inspected every third world country for nuclear weapons research.

No, but the guy in the office next to me has...Actually, he's only been to
Iraq. Twice. Anyway, since I directly addressed this point in the sentence
right after the one you quote above (see below), I'll just leave this one
alone.

>> The
>>threat of despotic countries seeking to develop nuclear weapons *is* real,
>>and requires more stringent efforts in UN inspections, non-proliferation
>>research, and development of both a defense against limited strikes and
>>the abililty to disable a "terrorist bomb."  Complaining about the "global
>>threat" won't make it go away.

>Nope, neither will ignoring it.

Here, at least, we agree. I even listed four things we can do to address the
problem rather than ignoring it.

>I suprised to hear that you think the present state of apparent nuclear threat
>is permanent.

Where'd you hear that?? Not in anything I wrote. I just got done saying
that the character of the threat had fundamentally changed. Those nasty
little despots you mention, like Sadaam, will ensure that we won't get rid
of *all* of our nukes (are you willing to bet your life on the efficacy of
the IAEA non-proliferation inspection regime? I'm not), but we can
certainly get by with less.

>>Haven't we had about enough of this [Malthusianism--ed.]in the last 200
>>years?? Ever since Malthus first came up with the idea, we've been in
>>Imminent Peril of choking the planet with people. Fortunately, there have
>>been enough people (!) cleverer than ol' Tom that we've managed well enough.
>>Try telling the people in Singapore, Japan, or Taiwan that high population
>>densities guarantee abject poverty and starvation. Ever stop to think there
>>might be more to it than that?

>Hmm. You're right. I feel better now. What's another 5 billion people anyway.
>I'm sure everything will be allllll right.

Good. I'm glad you've come to your senses...:)
--
 Dr. Donald W. Roberts
   University of California                                      Physicist
   Lawrence Livermore National Laboratory         Recreational Bodybuilder
   [e-mail]                                           Renaissance Dude

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

Date: Fri, 11 Sep 1992 14:52:58 GMT
From: Ron Baalke <[e-mail]>
Subject: Magellan Science Results Published
Newsgroups: sci.space,alt.sci.planetary

The "Journal of Geophysical Research - Planets" has dedicated two issues
of their journal to the science results of the Magellan mission.  I
have just received Part 1 today in the mail (Volume 97, Number E8, dated
August 25, 1992).  This hefty issue consists of 27 articles and over
600 pages.
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Anything is impossible if
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | you don't attempt it.
|_____|/  |_|/       |_____|/                     |

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

Date: Fri, 11 Sep 1992 06:23:34 GMT
From: "Michael V. Kent" <[e-mail]>
Subject: One Small Step for a Space Activist... Vol 3 No 9
Newsgroups: talk.politics.space,sci.space

In article <[e-mail]> [e-mail] writes:
>Then, [e-mail] (Allen W. Sherzer) replied:
>
>>As it currently stands Shuttle and Freedom together spend all the money
>>which could go toward a Shuttle replacement. NASA therefore intends
>>to use the Shuttle forever.
>
>Goldin says we should consider the Shuttle program to last "at least"
>until 2005, but not much beyond that.  12 years != forever.
>
>No word on where a Shuttle replacement might come from, or how it
>would be funded.

I, personally, believe a Delta Clipper, HL-20, or NASP-derived vehicle will
be funded very shortly after PMC (well, probably EMCC).

Mike

--
Michael Kent                                   [e-mail]
McDonnell Douglas                              Rensselaer Polytechnic Institute
All facts in this post are based on publicly available information.  All
opinions expressed are solely those of the author.    Apple II Forever !!

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

Date: Fri, 11 Sep 1992 13:50:34 GMT
From: Ron Baalke <[e-mail]>
Subject: Pluto Direct/ options
Newsgroups: sci.space,alt.sci.planetary

In article <[e-mail]>, [e-mail] (Nick Janow) writes...
>
>Would it be possible to aerobrake at Uranus or Neptune, perhaps also using the
>atmosphere to change trajectory significantly?  This would provide a fast
>flight for much of the journey and have the remaining part at a speed slow
>enough for aerobraking in Pluto's atmosphere, or at least a much slower pass by
>Pluto.  It would also allow a mission at Uranus or Neptune.

I don't think the planets will cooperate on this.  In the early 1970's, the
outer planets were lined up so that a spacecraft could have slingshoted
from Jupiter to Saturn to Uranus to Neptune to Pluto via gravity assists.
In fact, this was the original Grand Tour envisioned for Voyager.  But
delayed funding caused the Pluto option to be dropped, and the alignment
among the other planets has worsened since then.  Voyager 2 just did
make the window for Uranus/Neptune.

The idea though is on the right track.  Some studies are being done at JPL
on aero-gravity assists.  Using aero-gravity assists, a spacecraft can
go from Earth to Pluto in only 5 years.
An aero-gravity assist is where an aerodynamic spacecraft (called a waverider)
flies in very close to a planet through its atmosphere such that the lift
force balances the centrifugal force, and the resulting trajectory change is
better than that of a traditonal gravity assist.  There is some loss of
velocity due to atomspheric drag, but that is more than compensated for by
the gain in the trajectory deflection.   The 5 year trajectory to Pluto has
been worked out using aero-gravity assists of Venus and Mars.  It also turns
out that Mars is the best planet in most cases to use aero-gravity assists on.

There are some issues to be resolved to make aero-gravity assist a
reality.  The shape of the spacecraft has to be long and slender with a
sharp leading edge, and more research is needed to determine the
optimal shape.  There are also some uncertainties about the heating rates
of the spacecraft through an atmosphere of carbon dioxide.

Angus McRonald and James Randolph from JPL have done the research into
aero-gravity assists, and they have published their results in the
March/April 1992 issue of the Journal of Spacecraft and Rockets.
This is highly recommended reading.
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Anything is impossible if
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | you don't attempt it.
|_____|/  |_|/       |_____|/                     |

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

Date: 11 Sep 92 07:24:32 GMT
From: Nick Janow <[e-mail]>
Subject: Pluto Fast Flyby mission goals...
Newsgroups: sci.space

[e-mail] (Horowitz, Irwin Kennet) writes:

> Hearing all these wild ideas passed around on this Pluto flyby has led me to
> try to remind everyone of a few things concerning this mission. ....
> Remember, the last thing we need is to overdesign this mission like
> CRAF/Cassini.

Playing with ideas can also turn up useful, feasible techniques, along the
lines of the "Grand Tour" path using gravitational assists.  I doubt that
anything we post here will affect the Pluto missions, unless someone comes up
with a new idea too brilliant to pass up.

So stop spoiling being a wet blanket; we're having fun.  :)

--

[e-mail]

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

End of Space Digest Volume 15 : Issue 186
------------------------------