Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v15_2/v15no243.txt

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Date: Thu, 24 Sep 92 05:04:14
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #243
To: Space Digest Readers
Precedence: bulk


Space Digest                Thu, 24 Sep 92       Volume 15 : Issue 243

Today's Topics:
                      Clinton and Space Funding
                       Ethics of terra-forming
                         Ion for Pluto Direct
              Ion for Pluto Direct was Re: Pluto Direct
                       overpopulation (2 msgs)
                  program for interplanetary travel
     PUTTING VENUS IN AN ORBIT SIMILAR TO THE ORBIT OF THE EARTH
                           Radio allocation
                     Robot Rovers: Big or Small?
                      Sayonara, Mariner Mark II
                            SETI (2 msgs)
                    Solar radiation and astronauts
            Space Platforms (political, not physical : -)
                            Star database
                          Titan IV? (3 msgs)
  Using Electric Rockets for Science (was Re: Ion for Pluto Direct)

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

Date: 23 Sep 92 18:45:18 GMT
From: Robert Nehls <rn11195@sage>
Subject: Clinton and Space Funding
Newsgroups: sci.space,sci.astro,talk.politics.space,alt.politics.bush,alt.politics.clinton

[e-mail] (Mark 'Henry' Komarinski) writes:
: [e-mail] (Andrew Ford @ AGCS, Phoenix, Arizona) writes:
:
: >In article <[e-mail]>, [e-mail] (Doug Mohney) writes:
: >> In article <[e-mail]>, [e-mail] (Elizabeth G. Levy) writes:
: >> >
: >> >Military research will probably be cut.  As I pointed out, this is not
: >> >necessarily a very bad thing, since this kind of research is no longer
: >> >economically beneficial.  And you're probably totally off base, given
: >> >the voting records and policy statements of Clinton/Gore.
: >>
: >> Wrong on both counts. How do you define "economically beneficial"? The Global
: >> Positioning System is one pretty nifty spin-off from the Evil Military, hm?
: >> Smaller computers? Smart-optics compensation for telescopes?
: >>
: >>
: >And remember that the current day cellular radio telephones are only feasible
: >because of the military R&D in semiconductor electronics: without the
: >current day VLSI CMOS chips, the cellular telephone (car phone) would
: >require a semi-trailer to hold the electronics and most of the engine's
: >output to power it.
:
: [Benefits of military spending, etc...]
:
: >Military R&D provides jobs (Damn good paying jobs) not only for
: >those who do the work, but also for a great deal more who make
: >the supplies for the work.
:
: So what about the benefits from just plain space exploration?  Imagine the
: spinoffs once we get a space platform working, or get a colony on the moon?
: Or for that matter, make it to the moon again.  The benfits of this
: could be huge.  At the same time, people are getting employed and less
: money is going to trying to kill someone else.
:                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^
: -Mark
:
: --
Mark,
Contrary to popular belief, the majority of R and D money for the armed
forced goes into communications, advanced IC technologies, computer
technology, and various other non-lethal activities.  Sure some money does
go into weapons research, but they are they ARMED FORCES aren't they.  Now
don't get me wrong, I have no problem with reducing defense R and D spending
as long as the money goes into other R and D activities and people don't
lose their jobs.  Like it or not, the two main technology drivers for the
last 5 decades have been first the military and then the space program.
Billions of dollars have been cut from the defense budget.  Where has this
money gone?  No one talks about that.  The deficit hasn't been cut, new jobs
haven't been created, and the country on the whole is worse off due to the
unemployment increase.  Do you really think that it is a coincidence that
the military and space budget cuts coincide with the Japenese gaining a
technological edge?  Please don't spout off about cutting defense spending
until there are valid places for the money to go.  This idea of cutting
first and then trying to figure out what to do with the money later does
nothing for the country except increase unemployment and sacrifice our
technological edge.
--

Bob Nehls                             Sr. Design Engineer
[e-mail]            [phone]

Working Towards Full Life...

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

Date: 23 Sep 92 14:46:30 GMT
From: Sergio Marco Duarte <[e-mail]>
Subject: Ethics of terra-forming
Newsgroups: sci.space

>     In article <[e-mail]> [e-mail] (Tom) writes:
>   >
>   >'Right' is a legal term, not a moral one.
>   It is a philosophic one that is the basis of law.
>
>   >1) There isn't a god.
>
>   Prove it. You ought to be able to do that easily since you are so adamant
>   about it.

>   >This is an argument against acting without forethought, but not an argument
>   >against terra-forming.

>   Hey, I'm all for terraforming if you can show me how it's going
>   to be done.

 Perhaps if we all prayed hard enough for a few well aimed comets. :-)



>   But of course it is always the same -- we _could_
>   do it if only twenty sciences made major breakthroughs.

--
 Sergio Duarte  *** [e-mail] *** FCT/UNL *** PORTUGAL

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

Date: 23 Sep 92 19:12:24 GMT
From: Dan Vento <[e-mail]>
Subject: Ion for Pluto Direct
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] ("Phil G.
Fraering") wrote:
>
>
> Dave Tholen writes:
>
> \The current Pluto flyby mission design calls for chemical rockets and NO
> /Jupiter flyby, and the flight time is about seven years.  Your posting seems
> \to be claiming that an ion drive can place twice the payload into orbit around
> /Pluto with a flight time of about 3.5 years.  If this were true, I'm quite
> \certain that the Outer Planets Science Working Group would have heard of it.
>
> "If it were better, we would have considered it."
>
> I don't want "because". I want the real reasons...
>
> --
> Phil Fraering [e-mail] where the x is a number from 1-5.
> Phone: [phone] SnailMail: 2408 Blue Haven Dr., New Iberia, La. 70560
> "NOAH!"
> "Yes Lord?"                          - Bill Cosby
> "HOW LONG CAN YOU TREAD WATER?"


                      2
It is true! S=1/2 a t    . Even if a is only .001g (about what you get from
ion engines) t becomes quite small. Run the numbers, you will be surprised!

Dan Vento
[e-mail]

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

Date: 23 Sep 92 19:20:05 GMT
From: Dan Vento <[e-mail]>
Subject: Ion for Pluto Direct was Re: Pluto Direct
Newsgroups: sci.space

>
> But seriously, please keep in mind that I'm not against the development of
> ion drive technology.  Our primary goal is to get a spacecraft to Pluto
> while conditions for the study of the planet are most favorable.  Fiscal
> realities MUST be considered, or else we're just asking for another CRAF.
> If ion can be shown to do the job "faster, cheaper, smarter", I'll be the
> first to endorse the concept.  Our goal is the science, not the technology.
> With the budget crunch, we must be satisfied with good enough, even though
> we know that some technology can make things better.


One thing to keep in mind about the state of ion propulsion is that the US
Halleys comet mission - which was cancelled - was going to be propelled by
ion engines and the s/c was supposed to actually match orbit with the
comet! The technology was ready, the Congress chose not to spend the money.


Dan Vento
[e-mail]

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

Date: 23 Sep 92 19:39:30 GMT
From: Steinn Sigurdsson <[e-mail]>
Subject: overpopulation
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Thomas H. Kunich) writes:


   >   >expanding space colonies, or a growing population on a terraformed Mars,
   >   >is in jeopardy if, as demographics indicate, a technologically
   >   >sophisticated population with perfect birth control would have
   >   >birth rate of less than 1.0 per couple per lifetime, or a population
   >   >decline of 50%/generation.

   >   At least three things could change this.  The people who wanted
   >   to move to the colony might tend to be people who wanted to have
   >   larger families.  The colony developers might offer special
   >   incentives to attract people who wanted larger families or
   >   encourage people to have larger families than they otherwise

   >The easiest way to nudge the demographics up again is to
   >provide good easy access child care and tax breaks or other
   >direct financial incentives. Or a radical social change,
   >although there might be some objections to, for example,
   >some drastic changes in women's social status...

   Aren't you all missing the point that the growth of Earth's
   population will level off somewhere around three times the present
   population around the same time that cheap energy is getting scarce?


Current best WAG is twice present population if current trends
continue, maybe less if current trends evolve, conceivably as high
as three times if you're paranoid... and of course << present if
you're a real gloomer ;-)
    Now, what's this about cheap energy getting scarce?
Irrelevant in the context of the debate anyway, which assumed
certain demographics and social structures - question was how
to reverse the deomgraphic trends _in_that_scenario_, won't be
a problem if energy gets real expensive :-(

|  Steinn Sigurdsson    |I saw two shooting stars last night        |
|  Lick Observatory    |I wished on them but they were only satellites    |
| [e-mail] |Is it wrong to wish on space hardware?        |
| "standard disclaimer"    |I wish, I wish, I wish you'd care - B.B. 1983    |

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

Date: 23 Sep 92 20:39:13 GMT
From: David C Daye <[e-mail]>
Subject: overpopulation
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Nick Szabo) writes:

>    [....]         and the biggest problem is long-term population
>_decline_ and the problems it brings, like   [...]  loss of
>cultural and genetic diversity.

At what point does this kick in?  Wasn't world population 99% below present,
some time after the Ice Age, and haven't we come along fairly nicely out of
that small population?

>
>For those of us interested in the prospect of civilization's expansion
>into space, this is an especially serious problem.
> [...]
>                                            a technologically
>sophisticated population with perfect birth control would have
>birth rate of less than 1.0 per couple per lifetime, or a population
>decline of 50%/generation.

It sure was different in my family.   These people regarded anything
other than "perfect birth control" to be gross irresponsibility as far
back as we can trace, and in fact were pretty hostile, in the past, to
those who took any other approach.

Yet when they immigrated to urban Chicago they set up a pretty big family
because circumstances permitted it.

> [....]               I ask why does not this apply to developed
>countries, where couples have less than 2.0 children per lifetime,
>and the resources are much greater than in Africa, with 7 children
>per lifetime?

A) Developed countries have pensions and social security; couples don't
need to make enough babies to ensure that 3-4 are around to care for
them in old age;  B) Developed populations are mostly non-agricultural,
and don't need the extra hands to harvest next year's meals.  The fact
that family size does respond to changes in economic circumstances
shows that immediate self interest is pretty important in family
planning.

One element of that self interest is the enormous energy
drain of child rearing, which is why family size drops when it doesn't
have to be high.  Nature has ways to make us do things that are energy-
draining; it makes them *lots* of fun.  Direct your creativity towards
making childrearing less demanding and/or *lots* of fun in your space
colony, and your concerns will be answered.  Maybe the bio-tech people
-- oh, I don't even want to speculate!!  :)

>                         Fertility, not physical resources, is
>the main barrier to human expansion through the cosmos.

I think this is pessimistic.  If you give me the same deal at a space
colony that my old-country ancestors got in America (a cheap ride over,
and greatly expanded opportunies upon arrival), I'll seriously consider
going over and making you as many babies as I need and can support
under the circumstances there.

>[e-mail]        Tuesday, November third  ##  Libertarian  $$  vote

David Daye.

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

Date: 23 Sep 92 14:04:36 GMT
From: Roger Fujii <media!rmf>
Subject: program for interplanetary travel
Newsgroups: sci.space

Does anyone know of a program that is publically available (not necessarily
public domain) that does the calculations for a spacecraft travelling
through the solar system?  For example, I wanted to know if a
spacecraft weighing N tons can make it from here to Mars with M fuel in
6 months.  I have some of the basic equations, but I am not sure
if I have all that I need.  Any response would be welcomed.

Thanks in advance...
--
Roger Fujii - Media Cybernetics            Phone: [phone] x259
Internet: [e-mail]        UUCP: {uunet,hqda-ai}!media!rmf

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

Date: 23 Sep 92 20:01:33 GMT
From: [e-mail]
Subject: PUTTING VENUS IN AN ORBIT SIMILAR TO THE ORBIT OF THE EARTH
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Tom Nugent       ) writes:
> How exactly do you propose to move an ENTIRE GODDAMN PLANET?????  The
> machinery to terraform a planet is peanuts compared to what you would
> need to do to move a planet.

Oddly enough, we're discussing that in alt.sci.planetary.  I propose
stap-on laser boosters.  Take a look at that string, if you're lucky
enough to receive alt.* newsgroups.

-- Ken Jenks, NASA/JSC/GM2, Space Shuttle Program Office
      [e-mail]  [phone]

                  "HERE MEN FROM THE PLANET EARTH
                    FIRST SET FOOT UPON THE MOON
                           JULY 1969, A.D.
                  WE CAME IN PEACE FOR ALL MANKIND."

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

Date: 23 Sep 92 07:48:46 GMT
From: [e-mail]
Subject: Radio allocation
Newsgroups: sci.space

In <[e-mail]> Dillon Pyron writes:
>Try this one: "If those people are going to beam signals into my backyard, I
>have a right to use them".  Just let me know what prison they assign you to,
>I'll write.
  That line of argument works in Australia. A dozen or so years back,
there was a case where a farmer was picking up free electricity by
induction from the HT lines which ran just outside his property. He was
sued by the power company, they lost. :-)

 -----------------------------------------------------------------
               ** Of course I don't speak for IBM **
Greg Nicholls ... [e-mail] or [e-mail]
                  voice/fax: [phone]

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

Date: 23 Sep 92 22:26:26 GMT
From: Karl Altenburg <[e-mail]>
Subject: Robot Rovers: Big or Small?
Newsgroups: sci.space

I would like to know peoples ideas on which types of robots should be
used in possible, future Lunar and Mars missions.

Some support the traditional large rover.  An example would be Carnegie
Mellon's Ambler, which has 6 legs legs (non-traditional), complex vision
system, stands around 14 feet tall, and weighs a ton (I think?).
It would be launched and work as a solitary rover.

Others support the non-traditional, small (insect-like), multiple,
cooperative rovers.  An example of this type of robot would be JPL's
Rockey III, at has six wheels, 24 X 20 X 16 inches, and weighs about
60 pounds (the proposed Rocky IV will weigh less than 20 pounds.)
Several of these would be launched and work collectively.

I realize there are many issues involved, but I would like informed
opinions on the different views to exploring space.

--
Karl R Altenburg                [e-mail]
North Dakota State University, Fargo, ND  58105

All things are artificial, for nature is the art of God.  SIR THOMAS BROWNE

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

Date: 23 Sep 92 18:04:51 GMT
From: "Don M. Gibson" <[e-mail]>
Subject: Sayonara, Mariner Mark II
Newsgroups: sci.space

>
>Yes but how many people dream of building a planetary mission (I am one by the
>way). Children dream of goin into space and being astronauts.  That is why
>their are space camps springing up all over the planet.  This will in the
>long run bring more money to planetary science than all the ranting and raving
>in the world.  By the way planetary spacecraft construction is my forte Nick
>BUT I am a realist and I recognize what it will take to gain long lasting
>support for space and that is manned missions and Space Station Freedom.

That makes no sense to me.  Many more people dream of being a rock
star than a scientist developing new vaccines, but
vaccines still need to be developed.  Maybe the problem is basing funding
on the fantasies of people instead of the value of the science.  Forgive
me for raving, but I don't think that NASA should soley be in the business of
raising interest in "space camps".

>
>By the way there are several small faster cheaper mission being planned at
>JPL right now.  The cancellation of CRAF probably did more to HELP the long
>range goals of the planetary program than anything else in recent years.
Not.  MMII was going to advance craft dramatically.

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

Date: 23 Sep 92 15:36:37 GMT
From: Richard Murphy <[e-mail]>
Subject: SETI
Newsgroups: sci.space

When I worked at Arecibo in the early 80s the astronomers would
sometimes talk about signals that appeared to be artficial. Most
turned out to be interference from earth based sources. There was`
a very exciting event one day when a signal was found that
apparently was sidereally fixed. It turned out to be an equipment
glitch. However, I heard several times of signals that were
monitored once and never heard again that could not be classified
as obviously of earthly origin. If it's only heard once, there's
not much that can be done to figure out what it was.

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

Date: 23 Sep 92 20:45:11 GMT
From: Henry Spencer <[e-mail]>
Subject: SETI
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Richard Murphy) writes:
>... However, I heard several times of signals that were
>monitored once and never heard again that could not be classified
>as obviously of earthly origin. If it's only heard once, there's
>not much that can be done to figure out what it was.

As I recall, the usual procedure -- assuming you can get the signal to
sit still and be studied :-) -- is to ask another observatory to confirm.
This cuts out most Earthly sources.
--
There is nothing wrong with making      | Henry Spencer @ U of Toronto Zoology
mistakes, but... make *new* ones. -D.Sim|  [e-mail]  utzoo!henry

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

Date: 23 Sep 92 18:44:24 GMT
From: Frank Crary <[e-mail]>
Subject: Solar radiation and astronauts
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>>The rate actually depends on the solar cycle also: For some reason
>>cosmic rays are less intense during the solar maximum.

>Of course, this is somewhat of a no-win situation, because major solar
>flares are much more likely during the maximum...

Not totally: Flares aren't too hard to deal with (via storm shelters).
So flying long missions during the solar max is safer (you can live
with the flares and it cuts cosmic ray dosage in half...)

                                                 Frank Crary
                                                 CU Boulder

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

Date: 23 Sep 92 18:47:00 GMT
From: Barry Schlesinger <[e-mail]>
Subject: Space Platforms (political, not physical : -)
Newsgroups: sci.space

    Continuing the radio spectrum allocation debate that started
on this thread.

    It has been argued that frequencies like the 21 cm line would
be protected under the ground of existing use.  However, supposing the
free market model had been in effect all along.  Then perhaps at the
time its importance was discovered, the price would have been
prohibitive and the frequency not available.

    Apparently, this discussion is old hat on some of the news
groups to which this thread has been posted.  I am keeping it only on
sci.space, where I first saw it and where it has not been done to
death.  (We don't get talk.politics.space; apparently to keep people
from spending too much time arguing about the space program 1/2:-) ).

                my own views only

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

Date: 23 Sep 92 17:49:29 GMT
From: David Drum <[e-mail]>
Subject: Star database
Newsgroups: sci.space

Hello again,

Thanks to all who responded - I FTP'd a copy of the Yale BSC from pomona.
I'll let you know how it turns out, and maybe put some GIFs on an FTP site
somewhere.

Regards,

David

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

Date: 23 Sep 92 19:37:42 GMT
From: Lee Mellinger <[e-mail]>
Subject: Titan IV?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (John McDonald) writes:
:Is the Mars Observer being launched on the new Titan IV,
:or on the Titan III (similar to those that launched
:Voyager and Viking) ?
:
:johnny


Titan III.
:
Lee

"Nothing blasts forever" -- Keats on ammo.

|Lee F. Mellinger                 Caltech/Jet Propulsion Laboratory - NASA
|4800 Oak Grove Drive, Pasadena, CA 91109 818/354-1163  FTS 792-1163
|[e-mail]
:
:

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

Date: 23 Sep 92 19:28:26 GMT
From: John McDonald <[e-mail]>
Subject: Titan IV?
Newsgroups: sci.space

Is the Mars Observer being launched on the new Titan IV,
or on the Titan III (similar to those that launched
Voyager and Viking) ?

If not, what is the planned first launch of a Titan IV?

Thanks!

johnny

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

Date: 23 Sep 92 20:49:18 GMT
From: Henry Spencer <[e-mail]>
Subject: Titan IV?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (John McDonald) writes:
>Is the Mars Observer being launched on the new Titan IV,
>or on the Titan III (similar to those that launched
>Voyager and Viking) ?

Titan III.  In fact I believe it's a Commercial Titan, insofar as anything
bought by NASA can be called "commercial"... :-)  It's actually slightly
less hefty than the configuration that launched Voyager and Viking, because
the final stage is the solid-fuel TOS rather than a Centaur.

>If not, what is the planned first launch of a Titan IV?

Titan IV has flown several times, carrying classified military payloads.
The USAF owns it.
--
There is nothing wrong with making      | Henry Spencer @ U of Toronto Zoology
mistakes, but... make *new* ones. -D.Sim|  [e-mail]  utzoo!henry

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

Date: 23 Sep 92 19:08:26 GMT
From: Dan Vento <[e-mail]>
Subject: Using Electric Rockets for Science (was Re: Ion for Pluto Direct)
Newsgroups: sci.space

In article <[e-mail]>,
[e-mail] (robert.f.casey) wrote:
>
> Possible test mission for ion engines:  Launch it to an Earth orbit high
> enough to be out of the atmosphere to work (LEO?).  Then fly it around
> (maybe spiral out to the Moon's orbit) the Earth for a while.  Then
> fly it back down to LEO, and have a shuttle pick it up and bring it back
> to your lab for a complete examination.  Spend a few years cruseing the
> space near the Earth (changing orbital plains, etc).  Put a few ion
> engines on your test craft, so you can do statistal studies when you
> get it back.  Can we afford this sort of test?

Ion engines have been tested in space! On February 3, 1970 the NASA Lewis
Research Center launched the Space Electric Rocket Test (SERT II) into a
620 Mile orbit. SERT II was solar powered and thus could only operate when
the solor panels were in sunlight, they operated one thruster for six
months and the other thruster for eight months. The thrusters required 1.5
kW of power to operate. The spacecraft still is in orbit and operating (but
out of fuel).

The really big problem with ion propulsion to the outer planets is that a
adequate power source does not exist. You cannot use solar panels for that
kind of mission much beyon the orbit of Mars -- they would need to be
*very* large. A nuclear reactor is about the only source you could use to
power the engines, and aside from the obvious political problems of trying
to launch the reactor, I don't think the technology is ready for this kind
of long duration mission.



Dan Vento
[e-mail]

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


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Date:  Wed, 23 Sep 92 20:38:43 EDT
From: Tom <[e-mail]>
To: Space Digest <[e-mail]>
Subject:   Clintonomics and Space (non) Funding


>>I, personally, vote for what I think is best for the
>>society in general and not just my individual interests.

>Me too. I have absolutely no personal interest in space. I am not employed
>by NASA or any space related effort. I will not profit by any particular
>space policy.

Oh, don't be too sure.  I'm certain that we'll all profit from the right
space policies, but I don't think Clinton's is it. It sounds like
more of the same as the last 8 years, with less financial sense, if
that's even possible.

If this goof gets elected after all but promising to raise taxes $1.5E11
BEFORE the election, think of the things he'll do once he's in.  Brrr...

-Tommy Mac                     .  "                  +
.------------------------  +                      *       +
|   Tom McWilliams; scrub       ,     .                        "        +
|  astronomy undergrad, at     *       +;.     .  '             There is
| Michigan State University   '                      .    "   no Gosh!
|   [e-mail]                        '      ,   *
|       [phone]       ;  +  '                                 *
'-----------------------

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

End of Space Digest Volume 15 : Issue 243
------------------------------