Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT_ZIP/spacedig/V16_6/V16NO699.ZIP/V16NO699

Internet Message Format | 1993-07-13 | 31KB

Date: Tue,  8 Jun 93 05:18:27
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #699
To: Space Digest Readers
Precedence: bulk


Space Digest                Tue,  8 Jun 93       Volume 16 : Issue 699

Today's Topics:
           1992 NASA Authorization Budget- shuttle (2 msgs)
                  Big Rock Can Hit Earth in Yr 2000
                        DC-X neighbor (2 msgs)
              Detecting planets in other system (2 msgs)
                     Hypersonic Buzz Bombs in Qld
                    Limits Seen On Human Existence
         manifest destiny = US getting uppity again (2 msgs)
                   Mars Observer Update - 06/07/93
                        mass drivers (2 msgs)
               Mission planner, Mars Observer, NASA, AZ
                          Moon Base (2 msgs)
                        No Planet X? (2 msgs)

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

Date: 7 Jun 1993 19:37:23 GMT
From: Greg Moore <[e-mail]>
Subject: 1992 NASA Authorization Budget- shuttle
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Gary Coffman) writes:
>
>Well the Concorde hasn't exactly been a rousing financial success,
>but Boeing and Lockheed are still chomping at the bit to produce
>a Pacific Rim SST that should be on sounder economic ground. The
>Concorde is too small, and has too short a range, to cash in on
>the more profitable routes. Environmental concerns may doom the
>SST industry, but taking Concorde's lack of financial success
>as the bellweather of all SSTs is a bit naive.
>
    To paraphrase Allen, Just because the Concorde failed,
doesn't mean that Boeing will fail.

>Gary
>
>--
>Gary Coffman KE4ZV          |    You make it,     | gatech!wa4mei!ke4zv!gary
>Destructive Testing Systems |    we break it.     | uunet!rsiatl!ke4zv!gary
>534 Shannon Way             |    Guaranteed!      | emory!kd4nc!ke4zv!gary
>Lawrenceville, GA 30244     |                     |

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

Date: Mon, 7 Jun 1993 19:56:32 GMT
From: Paul Dietz <[e-mail]>
Subject: 1992 NASA Authorization Budget- shuttle
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Gary Coffman) writes:

> Well the Concorde hasn't exactly been a rousing financial success,
> but Boeing and Lockheed are still chomping at the bit to produce
> a Pacific Rim SST that should be on sounder economic ground. The
> Concorde is too small, and has too short a range, to cash in on
> the more profitable routes. Environmental concerns may doom the
> SST industry, but taking Concorde's lack of financial success
> as the bellweather of all SSTs is a bit naive.


Well, they may be chomping at the Federal Feedbag, but I don't
see them investing enormous amounts of their own money.

The environmental concerns seem less valid now.  Scientists now
believe that NOx in the stratosphere is more quickly removed
to inactive forms (N2O5, nitric acid), so SSTs would pose little
if any danger to ozone.  This is in a sense the opposite of what
happened with chlorine, where new reactions were found to have
the opposite effect.  Indeed, one problem with chlorine is that
it becomes more destructive when odd nitrogen is removed (by
precipitation of nitric acid trihydrate particles).

    Paul

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

Date: Mon, 7 Jun 93 17:24:34 GMT
From: [e-mail]
Subject: Big Rock Can Hit Earth in Yr 2000
Newsgroups: sci.space,sci.astro

In article <[e-mail]>, [e-mail] (Ron Baalke) writes:
[in rerfrence to asteroid flyby]
> Actually, it will be flying closer in 2004, but not as close as the
> moon's orbital radius.  Here are the closest approach numbers:
>
>     1992    .024 AU  (2.2 million miles)
>     1996    .035 AU  (3.3 million miles)
>     2000    .074 AU  (6.9 million miles)
>     2004    .010 AU  (0.9 million miles)
>
> We'll be bouncing more radar using Goldstone's 70 meter antenna on each pass.
> There is a possibility that the Clementine II mission may rendezvous with
> the asteroid in 1996.

Ron, what is the error bar on your .9 million mile figure?!!

Matt Sexton    [e-mail]

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

Date: Mon, 7 Jun 1993 18:57:48 GMT
From: "Richard A. Schumacher" <[e-mail]>
Subject: DC-X neighbor
Newsgroups: sci.space

In <[e-mail]> [e-mail] (Andy Cohen) writes:

>RPV controls....  Lots of graphics and animation....  It really made me
>sick...  We've been working towards that on SSF for 5 long slow years while
>they [DC-X] pulled it off in less then 18 months.....

Care to comment on why that is?


>A lot of the hardware....i.e., hinges, rivets, cables and stuff.... comes
>from Home Depot.

Maybe that's why.

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

Date: 7 Jun 1993 19:54:57 GMT
From: Andy Cohen <[e-mail]>
Subject: DC-X neighbor
Newsgroups: sci.space

In article <[e-mail]>, [e-mail]
(Richard A. Schumacher) wrote:
>
> In <[e-mail]> [e-mail] (Andy Cohen) writes:
>
> >RPV controls....  Lots of graphics and animation....  It really made me
> >sick...  We've been working towards that on SSF for 5 long slow years while
> >they [DC-X] pulled it off in less then 18 months.....
>
> Care to comment on why that is?
>
>
> >A lot of the hardware....i.e., hinges, rivets, cables and stuff.... comes
> >from Home Depot.
>
> Maybe that's why.

I assume you are asking why the difference in time between the two
programs....

1. DC-X is not a man-rated system....
2. SSF is a long term NASA program....it requires redundancy, updates and
maintenance.
3. The DC-X customer did not require documentation in triplicate.  In fact
I hear that the customer requires only enough docs needed to get the bird
to fly.
4. The SSF went through one,....soon to be two, major redesigns...
5. DC-X is simple, SSF is complex....both in the extreme...

I could go on and on....  One can turn this into an anti-SSF thread due to
these differences.... I hope this does not happen...  It would not be
fair....

What's also not fair is option A for $17B, option B for $19B and...... C
for $14-15B.  We saw the slides for A and C and know these WAGs ain't
true.....(IMHO)!

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

Date: Mon, 7 Jun 1993 13:08:57 MST
From: "Richard Schroeppel" <[e-mail]>
Subject: Detecting planets in other system

<attribution lost:>
>>But your approach won't work: You can't "put the star on a null, with
>>the planet at a peak" since you have no idea where the planet is...

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>Actually, you ought to be able to make a fair guess:  assume that you will
>get a Jupiter-like planet at about the distance where it gets cold enough
>for such a body to retain hydrogen.  Not a sure thing, but the odds ought
>to be fairly good.

Frank Crary <[e-mail]>:
>You could make a fair guess at the radius of the planet's orbit this
 way, but putting the planet at the peak of an interference pattern is
 much more difficuty: It's the angular seperation, not the radius
 that is required. That's a function of the orbital radius, inclination
 of the orbital plane to the observer and the position of the planet
 along its orbit. The last two factors can't be estimated.

<me>:
You can guess that the orientation of the planet's orbital plane is close
to the equatorial plane of the star.  The star's rotation axis might be
estimated by measuring tiny magnitude variations, and attributing them to
starspots rotating in and out of our view.

Rich Schroeppel  [e-mail]

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

Date: Mon, 7 Jun 1993 20:24:59 GMT
From: Henry Spencer <[e-mail]>
Subject: Detecting planets in other system
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Frank Crary) writes:
>>>But your approach won't work: You can't "put the star on a null, with
>>>the planet at a peak" since you have no idea where the planet is...
>>Actually, you ought to be able to make a fair guess...
>
>You could make a fair guess at the radius of the planet's orbit this
>way, but putting the planet at the peak of an interference pattern is
>much more difficuty: It's the angular seperation, not the radius
>that is required. That's a function of the orbital radius, inclination
>of the orbital plane to the observer and the position of the planet
>along its orbit. The last two factors can't be estimated.

Oops.  Right you are.  "Analysis of his tactics suggests two-dimensional
thinking..."

You could get around this with a relatively long-term observing program.
The thing will be out at maximum angular separation -- for which knowing
the radius is sufficient -- eventually.  But it would be a lot more hassle.
--
Altruism is a fine motive, but if you   | Henry Spencer @ U of Toronto Zoology
want results, greed works much better.  |  [e-mail]  utzoo!henry

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

Date: 7 Jun 93 18:48:01 GMT
From: John Hinkey <[e-mail]>
Subject: Hypersonic Buzz Bombs in Qld
Newsgroups: sci.space


\ ""Space Engine a first for Qld uni.  "The Cairns Post" Sat June 5
\
\         A world first in space engine technology by Queensland University
\  engineers this month has been likened to when the Wright brothers first
\ mastered flight 90 years ago.
\         It has opened a new gateway to space." said Professer Ray Stalker
\ who has been reaching for the stars for 30 years, developing the
\ revolutionary scramjet space engine to its now proven stage.
\         Cairns-based ship-builder and engineer NQEA Australia Pty Ltd
\ previously had been involved in the scramjet research.
\         Prof. Stalker said the scramjet concept had been around for 40
\ years but, so far, scientists around the world had been unable to prove
\ it was an engine capable of producing orbital flight.
\         Space flight is dominated by rocket propulsion which has the
\ drawback of requiring large amounts of oxygen fuel to escape earth's
\ gravitational pull.
\         Sub-orbital flight such as Germany's World War 2 V-2 buzz-bombs
\ used ramjet engines which sucked oxygen in at such force it was compressed
\ into fuel.

I believe the buzz bombs were subsonic and the V-2's were rockets.
Wouldn't it be great if we could
compress oxygen ( air? ) into fuel.  An atmosphere made of monopropellant!
Boy, wouldn't that solve a lot of problems.  Nobody on the net would have
anything to talk (argue) about!

\         The only hitch there was the intake and compression slowed the
\ rocket down to about Mach 5, five times the speed of sound," Prof Stalker
\ said.

Yes, the total energy added to the air by burning the fuel (if you could get it to mix
and burn in time) isn't very much compared to the total enthalpy of the flow.
Tough to get alot of thrust (but maybe you can at Mach 7).

\       Scramjet engines are designed to suck oxygen in at such hypersonic
\ speed it ignites and produces forward thrust.

Oh come now,  are their science programs that bad?

\         The test flight inside the university's "Stalker Tube", a 24 metre
\ long shock tunnel involved a 300 mm prototype scramjet engine and miniature

\ spacecraft which reached a speed of 2.4 kilometers a second or Mach 7.2.

Well the "prototype scramjet engine and miniature spacecraft" were not moving
at 2.4 Km/s -  the air was moving past them at 2.4 Km/s.

\         Using highly sophisticated measuring devices the little model was
\ detected to leap forward an infinitesimal fraction of a millimeter in just
\ a millisecond.

This may be referring to the method of letting go of the model for a fraction
of a second and then catching it to determine aerodynamic coefficients
such as drag (thrust!), lift or moments (Cl, Cd or Cm).

Unfortunately the "steady-state" testing time of most "Stalker tubes"
is usually a millisecond or so.  I wouldn't put too much faith in these
results.

\         But that was enough for Pro Stalker and his team because it proved
\ the scramjet was an engine capable of producing forward thrust - and
\ flight.

Proved? - Maybe. I'd like to see some more tests.  It may be that the NASP
community (I used to be a member myself) is a bit desperate and
needs a little PR.

Don't take my comments the wrong way.  I think that scramjets can and
will work .. it's just that there is a very long way to go for SSTO to
use them.

\         "It's a major milestone. Never before has a scramjet vehicle
\ produced enough thrust to fly." he said.

It will be a real milestone when a full size vehicle produces usefull
amounts of thrust.

\ ______________________________________________________________________
\  Had to key this one in.... It is verbatim and probably syndicated from
\ Brisbane, Qld, Aust. Oz might have space class researchers but as far as
\ science journo's are concerned here is clear evidence not all our wide
\ open spaces are in the outback.                       Lawrie

It saddens me that so much incorrect technical information can be given
to the lay public without apparently being checked by anyone.  I'm not
talking about the in's and out's of testing models in "Stalker Tubes", but
about things such as "requiring large amounts of oxygen fuel " or
"Germany's World War 2 V-2 buzz-bombs used ramjet engines
which sucked oxygen in at such force it was compressed into fuel"

Don't worry Lawrie,  Aust. isn't the only place where there is
alot of wide open space .. the US of A has been
known to have quite a bit herself.



Replies? Comments?


            John Hinkey
            University of Washington
            [e-mail]

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

Date: Mon, 7 Jun 1993 19:54:32 GMT
From: [e-mail]
Subject: Limits Seen On Human Existence
Newsgroups: sci.space

In article <1ujvq9$[e-mail]> [e-mail] (Greg Moore) writes:
>In article <[e-mail]> [e-mail] (Christopher DeBoy) writes:

[... text deleted ...]
>    Two comments here.  First, using his theory, this could be true.
>However, knowing the history of HUMANS, we know that you have 7 months to
>about 90 years.  There is some intrinsic information available here.
>But, if you were the only human to ever exist, then yes, you might
>have 946 years.  Adam did, or something like that. :-)
>
>    I've deleted most of your argument above for space.
>I think from what little I've seen of the theory, that it fails to take
>into account free will.  i.e., it may be possible to predict the possible
>extinction of a species in general, but fails for humans.  Simply because
>humans can alter the equation.  Already we are seeing this.  Humans have
>stepped out of Darwinian Evolution, and are now evolving based on our
>brains, not on our genes.  We can alter the equation, we have and we will
>again.
>

That's exactly how they were trying to apply the theory... to predict
the likely lifetime of the human species, human activity like space
programs, and to start making decisions based upon what it predicts.
I agree completely that the theory fails in that it doesn't account for
'free will,' and becuse of that, it's completely useless for predicting
the lifetimes of such things to any degree of accuracy.

On the whole, from the article I got the impression that this theory is
simply a fancy round-about way of expressing the obvious -- that things
have a beginning, and a finite lifetime at the end of which they cease to
exist.  To say that I can expect to live anywhere between 7 months and
946 years is not terribly useful -- I'm not likely to alter significantly
the course of my life now that I know this.
--
__________________________________________________________________

Peter Schlumpf
[e-mail]

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

Date: Mon, 7 Jun 1993 20:02:17 GMT
From: Henry Spencer <[e-mail]>
Subject: manifest destiny = US getting uppity again
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Michael Sandy) writes:
>Howver, Canada has enough internal problems with Quebec and the Provinces
>to deal with Chicago, let alone the whole North American continent.

We're considering having a stray missile or two hit Chicago, sort of
accidentally...
--
Altruism is a fine motive, but if you   | Henry Spencer @ U of Toronto Zoology
want results, greed works much better.  |  [e-mail]  utzoo!henry

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

Date: Mon, 7 Jun 1993 21:09:03 GMT
From: James Davis Nicoll <[e-mail]>
Subject: manifest destiny = US getting uppity again
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] (Michael Sandy) writes:
>>Howver, Canada has enough internal problems with Quebec and the Provinces
>>to deal with Chicago, let alone the whole North American continent.
>
>We're considering having a stray missile or two hit Chicago, sort of
>accidentally...

    YES! Never to again have transfer at OHare is a boon worth  the
minor amount of fall-out a few airbursts would cause, esp. since most
of it would end up in Michigan.

    Two missiles seems like overkill, though. That could be 6 three-
hundred-fifty kiloton warheads, assuming minuteman IIIs. Of course, considering
the 100% failure-rate of minutemen fired from real silos, maybe we should
just ship the warheads UPS.

                            James Nicoll

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

Date: 7 Jun 1993 21:01 UT
From: Ron Baalke <[e-mail]>
Subject: Mars Observer Update - 06/07/93
Newsgroups: sci.space,sci.astro,alt.sci.planetary

Forwarded from the Mars Observer Project

                       MARS OBSERVER STATUS REPORT
                              June 7, 1993
                               2:00 PM PDT

The spacecraft is stable in Array Normal Spin.  Communication is via the High
Gain Antenna in Mission Mode; uplink at 125 bps, downlink is at the 4 kbps
data rate.  One Way Light Time is 14 minutes and 28 seconds.  The Payload Data
System, Gamma Ray Spectrometer and Magnetometer/Electron Reflectometer are
powered on.  GRS is operating from RAM.  Indications are that all spacecraft
subsystems and the instrument payload are performing well.  No Flight Sequences
are currently active.

The Flight Team commanded the spacecraft Script Buffer reinitialization and
uplinked Flight Sequence C11 today.  Activation of C11 occurs tomorrow
(Tuesday) at 9:00 AM.  Mars Observer Camera star imaging begins Wednesday at
9:00 AM and continues through July 1.

An all-day Preliminary Design Review of the Mapping Transition strategy takes
place tomorrow at JPL.  GRS canister deploy and boom extension, the
Magnetometer boom extension, Solar Array deployment, and High Gain Antenna
deployment will be detailed.  These deployments take place post-MOI (Mars
Orbit Insertion).
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | The tuatara, a lizard-like
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | reptile from New Zealand,
|_____|/  |_|/       |_____|/                     | has three eyes.

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

Date: Mon, 7 Jun 1993 20:27:19 GMT
From: Henry Spencer <[e-mail]>
Subject: mass drivers
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Paul Dietz) writes:
>... Control of lateral
>velocity to within less than 1 millimeter per second would be
>necessary to keep the mass catcher from being unacceptably large.  A
>subsequent feedback stage would be needed to correct these errors.  An
>electrostatic scheme was suggested.  Measuring these errors requires
>precise tracking down a path of tens of kilometers.

Note, though, that you don't need to track it every centimeter of the way.
You don't need a structure tens of km long, just tracking systems at a
few points downrange.
--
Altruism is a fine motive, but if you   | Henry Spencer @ U of Toronto Zoology
want results, greed works much better.  |  [e-mail]  utzoo!henry

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

Date: Mon, 7 Jun 1993 20:41:52 GMT
From: Henry Spencer <[e-mail]>
Subject: mass drivers
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Gary Coffman) writes:
>>But 10G is a ridiculously *low* acceleration, which nobody would use for
>>a practical system...  A practical lunar system would almost
>>certainly run at 1000G or more, making it only a few hundred meters long.
>
>What you're describing, Henry, is an electromagnetic *cannon*. I had
>in mind something with much lower peak energy requirements, more on
>the order of a linear induction motor...

As far as I know, nobody takes linear induction motors seriously any more
for this kind of application.  They simply do not scale well to useful
accelerations with major payloads.

A high-acceleration system is indeed what I'm describing, and what everybody
else is describing too.  Low-acceleration systems are obsolete due to
exactly the point you criticized:  they're long.  If you want to criticize
rockets, you criticize Ariane or Pegasus, not the V-2.

The energy requirements, for a given payload size, are precisely the same
(disregarding losses) for high or low acceleration.  What scales up with
acceleration is peak power requirements.  But if you don't insist on
individual payloads weighing tons, that's not a formidable problem.

>You could use a 1000 G launcher
>for bulk materials, but it'd require very high peak loads on the energy
>supply and on the structure, not to mention the buckets. That could
>run the cost of building it up more than laying out a longer system
>that had to handle lesser loads.

It has to run the cost up a whole lot before it matches the costs of
building a structure many km long.  1000G has been demonstrated; it does
not look like it requires exotic structure or hardware.

>Of course, if you only wanted to launch little pellets, it wouldn't
>be much of a problem, but if you wanted fairly hefty chunks, say
>for a hypothetical Al-O booster stage, circa 4,000 kg, it'd be absurd.

Why do you want to launch four tons at a time?  The laser-launcher folks
say that 20kg is enough for freight; the only larger lump that has to fly
is one piece is an astronaut.  (Although at Making Orbit, when Jordin Kare
said something along those lines, someone in the audience commented:  "I
work with astronauts, and there's some I'd *love* to launch into orbit in
20kg chunks".)

Incidentally, building rocket stages that can take 1000G is a solved problem.
--
Altruism is a fine motive, but if you   | Henry Spencer @ U of Toronto Zoology
want results, greed works much better.  |  [e-mail]  utzoo!henry

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

Date: Mon, 7 Jun 1993 21:11:01 GMT
From: Greg Mehall <[e-mail]>
Subject: Mission planner, Mars Observer, NASA, AZ
Newsgroups: sci.space,misc.jobs.offered

Mars Observer Job Opportunity

The Department of Geology at Arizona State University is currently looking
for personnel to staff the Mission Operations Center for the Mars Observer
Thermal Emission Spectrometer experiment. This instrument is a Fourier
transform infrared spectrometer, which will be used to determine the
composition of rocks, soils, ices, clouds and atmosphere on Mars.  Launch
of the spacecraft occurred on September 25, 1992, with arrival at Mars
in August of 1993.

Job Description:
Will be responsible for the planning of observations and generation of
instrument commands used to operate the Mars Observer Thermal Emission
Spectrometer (TES) experiment. Will manage the observation database and
participate in validation of data downlinked from Mars. These activities
will be performed on a computer workstation, and will involve extensive use
of mission operations planning software developed at ASU. Science observation
planning will require knowledge and application of complex procedures and
ability to work independently. Knowledge of the Martian surface and
atmosphere is required to plan observations. Will work directly with the
Science Team, and must be capable of translating science objectives and
strategies into actual observation sequences. Will participate in data
analysis and generation of scientific papers.

Qualifications:
Bachelor's degree in natural science (geology, physics, astronomy or
planetary science preferred), plus four years experience in science data
acquisition and/or analysis. Master's degree in natural science desired.
Prior experience and active participation with a research project is
required. Extensive knowledge of UNIX operating system is required and
experience with SUN workstations is highly desired. Prior experience with
spacecraft mission operations, data collection and data analysis is desired.

Position Information:
Anticipated salary is $25,000 to $30,000. Position is funded yearly and
could continue through 06/30/96, with continuation contingent upon NASA
funding. Applications will be accepted between May 1 and July 31, 1993.
Expected hire date will be between September 1 and October 1, 1993.

Unfortunately, we cannot consider Email replies. Please send letter of
application, resume and information for two potential references to:

Arizona State University
Human Resources - Employment
Attn: Mars Observer Research Specialist Senior
Box 871403
Tempe, AZ 85287

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

Date: Mon, 7 Jun 1993 19:43:56 GMT
From: [e-mail]
Subject: Moon Base
Newsgroups: sci.space

: In article <[e-mail]> [e-mail] (Gopinath Kuduvalli) writes:
: >Pray tell, what *are* these other reasons for long-term permanent presence
: >on the moon, mars or wherever in space?

Frank Crary ([e-mail]) wrote:
: The completely unacceptable (politically) but most direct answer is,
: "Manifest Destiny": The future is not on one, crowded, resource-depleated
: world.

John F. Kennedy said:

     "I believe that this nation should commit itself to achieving
      the goal, before this decade is out, of landing a man on the
      Moon and returning him safely to the Earth."

Ronald Reagan said:

     "It is mankind's manifest destiny to bring our humanity into space,
      to colonize this galaxy.  And as a nation, we have the power to
      determine whether America will lead or will follow.

      I say that America must lead."

George Bush said:

     "...back to the moon, back to the future,
      and, this time, back to stay."

Bill Clinton might as well have said,

     "Let's cancel that Space Exploration Initiative.  There are no
      voters on the moon."

-- Ken Jenks, NASA/JSC/DE44, Mission Operations, Space Station Systems
      [e-mail]  [phone]

    "This is Gene and I'm on the surface...  And as I take man's last
     steps from the surface, back home...  for some time to come, but
     we believe not too long into the future, I would like to just
     let...  what I believe history will record...  that America's
     challenge of today has forged man's destiny of tomorrow.

    "And as we leave the moon and Taurus-Littrow, we leave as we came
     and, God willing, as we shall return - with peace and hope for all
     mankind.

    "Godspeed the crew of Apollo 17."
       -- Gene Cernan, Apollo 17 Astronaut, the last man on the moon.
          For now.

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

Date: 7 Jun 93 20:47:11 GMT
From: Paul Dietz <[e-mail]>
Subject: Moon Base
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Gary Coffman) writes:

> Hall process aluminum refining doesn't require large amounts of volatiles,
> except in the preliminary Bayer process to turn the ore into alumina for
> the pot line.

No, it does, if you count carbon as a volatile.  The anode in the cell
is carbon; the anode is consumed stoichiometrically during the
electrolysis by reaction with the oxygen.  Folks have worked on
processes without consumable anodes, but they have not been
commercialized.

On the moon, if you used this process you'd have to recycle the carbon
back to again.  This could be done by a number of means, but would
add complexity.

    Paul

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

Date: 7 Jun 93 20:00:22 GMT
From: [e-mail]
Subject: No Planet X?
Newsgroups: sci.space,sci.astro,alt.sci.planetary

yes I thought this was implicit; obviously there are probably plenty
of small pluto-size bodies that inhabit the outer reaches of the
Solar System.

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

Date: Mon, 7 Jun 93 21:37:55 BST
From: Ata Etemadi <[e-mail]>
Subject: No Planet X?
Newsgroups: sci.astro,sci.space,alt.sci.planetary

In article <[e-mail]>, [e-mail] (Ron Baalke) writes:
-| Recent analysis by Dr. E. Myles Standish from JPL indicates that Planet X does
-| not exist.  Astronomers for over half a century have been searching for
-| Planet X based on what appeared to be irregularities in the orbits of
-| Uranus and Neptune.  However, when the extremely accurate measurements
-| of the mass of Neptune made by the Voyager 2 flyby in 1989 are
-| inserted in the equations, these irregularities vanish.  The mass of
-| Neptune is now known to be off by five-tenths of 1 percent.  When
-| the new value for Neptune's mass is factored into the equations, the orbits
-| of the outer planets are shown to be moving as expected, going all the
-| way back to the early 1800's.  The results of Dr. Standish's analysis are
-| published in the May issue of The Astronomical Journal.
-|      ___    _____     ___
-|     /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
-|     | | | |  __ \ /| | | |     Jet Propulsion Lab |
-|  ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | The tuatara, a lizard-like
-| /___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | reptile from New Zealand,
-| |_____|/  |_|/       |_____|/                     | has three eyes.
-|

Just as a matter of interest I remembered an object discovered by the
famous Thomas C. Kowal (I think that's the spelling :-) in '84ish was
dubbed the tenth planet. He went on to discover 2 other similar objects
(I think). So Planet X != 10th planet.

regards
    Ata <(|)>.

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End of Space Digest Volume 16 : Issue 699
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