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Subject: SPACE Digest V13 #741

SPACE Digest                                     Volume 13 : Issue 741

Today's Topics:
             Did I miss something
               Re: Risks of technology
                  Telescopes
             future astro funding
        Auroral observation from Australia, 13th June
    Platinum-group metal concentrations in earth-crossing objects
      Re: Excavating (minig) gold in the space by NASA.
            SPACE Digest V13 #625

Administrivia:

    Submissions to the SPACE Digest/sci.space should be mailed to
  [e-mail].  Other mail, esp. [un]subscription requests,
  should be sent to [e-mail], or, if urgent, to
             [e-mail]

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

Date: 11 Jun 91 11:23:34 GMT
From: pro-magic.cts.com![e-mail]
Subject: Did I miss something

I was away for a while and now I notice that the postings on the status of
all the various space missions is no longer on this newsfeed.

Did this cease in favor of all the summary postings I see, or was a new
newsfeed created just for the mission summaries?
------------------------------<<<Mike Ungerman>>>----------------------------
                           Proline:  mikeu@pro-magic
                 Internet: crash!pnet01![e-mail]
                  UUCP: (..uunet!tarpit!bilver!pro-magic!mikeu)
                  Arpa:  crash!pnet01!pro-magic![e-mail]
       Voice: 407-366-5840 | Prodigy: JSNP58A | Compuserve: 71326,31

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

Date: 13 Jun 91 15:24:18 GMT
From: att!news.cs.indiana.edu!maytag!watmath!watdragon!watyew![e-mail]  (James Davis Nicoll)
Subject: Re: Risks of technology

In article <[e-mail]> [e-mail] (Fraering Philip) writes:
>I think there is a risks group possibly as appropriate to discuss
>this stuff. Maybe people posting on that subject should crosspost.
>
>And my 2 cents: Well, the material will probably be broken up and shipped
>in small 10 ton pieces anyway...

    Hmmm. Ten (metric) tonnes at 8 km/s. That works out to 1.6x10**11 J,
or ~38onnes of TNT equivalent. I can live with that. What's the energy
content of a LNG tanker? If you design the rv right, most of that can be
dissipated in the air (I think). Oh, some chunks are bound to get through
at speeds higher than you'd want, but we're talking large chemical bomb
levels of damage, not nukes, and if you target expendible low poulation
regions (North West Territories, Nevada, Los Angeles..) the expected
um, losses should be within acceptable limits (Using car fatalities as
a guideline).

>And there seems to be the possibility of Tungusta style events in the
>future. If someone is worried about risks, now is the time to develop
>the technology to move the stuff...

    Not to mention the occasional targeting error will give us some
practise at dealing with the aftermath of a meteor strike .

                                James Nicoll

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

ReSent-Message-ID: <[e-mail]>
Resent-Date:  Thu, 13 Jun 91 12:20:45 EDT
Resent-From: Harold Pritchett <[e-mail]>
Resent-To: Space discussion group <[e-mail]>
Date:         Wed, 12 Jun 91 18:47:12 EDT
From: Tom McWilliams <[e-mail]>
Subject:      Telescopes
To: harold <[e-mail]>



----------------------------Original message----------------------------
Howdy.  About you homebuilt;

I've already seen all the posts people have sent you via space.sci,
so I will restrict myself to two thoughts.

One:  subscribe to Astonomy -or- Sky & Telescope, if you haven't already.
      You'll probably want to later, so you might as well now, so you
      can see other's ideas, manufacturers kits and finished scopes, and
      start getting familiar with the sky (in case you aren't now)

Two.  Go for apeture. This defines your diffraction limit, and you light-
      gathering power (in case you later get interested in deep-sky stuff).
      If you really are stuck on planets, get a refractor (since lacking a
      secondary mirror improves the diffraction limits)

Good luck.  I decided to buy a telescope, rather than build it myself,
  since I found a company that's selling me a dobsonian 10" for $350.00
  I might have ground it myself, but I understand that anything over 8"
is pretty tough for a novice grinder, and my interests are mainly deep-sky.
 (but don't miss the back-to-back conjunctions of Venus,Jupiter and Mars!)

(I guess that's three thoughts :-)
 Tom

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

Date: 14 Jun 91 01:38:50 GMT
From: theory.TC.Cornell.EDU![e-mail]  (Robert W. Nelson)
Subject: future astro funding

I've come to the pessimistic conclusion that astronomy/space science
funding is in serious trouble for the coming decade (not just in the
1992 budget), and would like to hear other opinions. Here is my reasoning:

(1) The space station will be funded and built in some form regardless
of its scientific usefulness. The aerospace industry wants this badly
since they will be hurting from the lack of new military contracts as
the cold war comes to an end. The astro/space community is a tiny
constituency compared with these big contractors and (as demonstrated
in last thursday's vote in the House) no amount of letter writing by
the ~ 4000 members of AAS will change this.

(2) The Earth Observing System will be funded and built in some form.
Holes in the Ozone layer and the Greenhouse effect has got people
scared, especially politicians who fear having to make real changes
in our energy policy. People will hope that throwing lots of money to
do research will make the problem go away. In addition, unlike the
space station, EOS will have strong support from most of the science
community. Astronomy/space scientists will have difficulty arguing that
it's not a very pressing problem.

(3) NASA funding will not increase significantly beyond inflation.
The budget agreement made last October does not allow for savings
in military funds to be transferred to domestic programs. Congress
is not going to cut veterans, and I strongly doubt that HUD will
be cut considerably.

With two giant programs coming on line in NASA, and without significant
increases in the total NASA budget, it seems to me that all other
"nonessential" programs within NASA, including Space Science and
Applications,  will have to take deep cuts. I don't see any other
way around this. If you see a hole in my reasoning I'd like to know.

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

Date: 14 Jun 91 02:47:29 GMT
From: munnari.oz.au!deakin.OZ.AU![e-mail]  (Ludwig Omachen)
Subject: Auroral observation from Australia, 13th June


This observation was from the southern coastline of Victoria,
Australia, (Near Geelong) on thursday 14th june,
from 10:30 pm till 11:30 pm local time (AEST).
Weather conditions were fine, almost cloudless sky with no moon.

Looking due south over the ocean, a whitish
(perhaps with greenish tinge) band approximately the thickness of a
rainbow extended in a horizontal arc of about 60 degrees with the hight
of the arc about twice its thickness above the horizon (Approx. 15
degrees above horizon at its peak).

Intermittent narrow vertical shafts of white light extended from this
horizontal band up to about 40 degrees above the horizon, also
accomanied by much broader areas or shafts or red light.

The most interesting observation was  the appearance of narrow
horizontal striations (within the horizontal white arc) which were
about twice as bright as the main band.
The thickness of these horizontal striations was about 10 percent of
the main band thickness, and their horizontal length about  20 to 30
percent of the main band's length.
These striations would appear at the bottom of the main band and move
rapidly upwards through the band and dissappear at the top of the main
band, this would take about Half a second, with numerous striations
repeating the same procedure.

The brightness was subjectively about 3 or 4 times that of the Milky
way, but not as bright as the last aurora which was visible here on
march 26th.
It was also further away, (not as high above the horizon as the march
sighting)


Ludwig Omachen                [e-mail]
Dept. of Computing and Mathematics    Ph. Work [phone]
Deakin University 3217            Ph. Home [phone]
Geelong, Victoria, Australia.

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

Date: 12 Jun 91 07:34:15 GMT
From: ogicse!sequent!muncher.sequent.com![e-mail]
Subject: Platinum-group metal concentrations in earth-crossing objects

In article <[e-mail]> [e-mail] (Hal Chambers) writes:

>... the asteroid is no more than 0.001% platinum and 0.0001% gold.
>How does this compare with terrestrial ores?...

The gold concentration is very poor -- its distribution in the
metal is fairly homogenous, from the limited meteorite studies
we have done to date. Unless we find concentrated ores or the space
environment gives us a _very_ large advantage in processing the
metal, we won't be able to efficiently get gold from this source.

10 ppm platinum is a pretty good ore, about matching the highest
concentrations found on Earth.  From the very crude media numbers,
this particular asteroid doesn't look very good, as asteroid metal
goes.

The best data we have come from the asteroid samples fallen to Earth,
meteorites, many of which contain metal or metal grains from core
material.  The best platinum-group concentrations have been
found in the metal grains of LL-type chondrites, as follows:

Platinum    21 ppm
Ruthenium    12
Osmium        10
Iridium        10
Rhenium        1.0

As an aside, they also contain 1-15 ppm gallium, 200 ppm germanium, and
1.2 ppm arsenic.   Space Industries Inc. is currently working on a
wake shield to produce large volumes of very high vacuum, which can
be used with microgravity to create GaAs and other semiconductors
with much greater purity than in Earthside semiconductor fabs.
GaAs is used for expensive, high-speed chips, for example in the
latest Cray supercomputer.  Asteroids could provide the raw materials
to produce very large quantities of these semiconductors, instead
of launching them from the Earth at $5,000/kg.

Back to platinum: we have a total of 55 ppm platinum group, about 5
times better than the best Earth ore.  This still wouldn't be that
good, given the high costs of launching mining equipment, except
that there exists a process which, taking advantage of the large
amounts of solar-thermal power available in space, could make
extracting the platinum economical.

First, we should find grains with the above concentrations or better
in a high-metal regolith (a task for space exploration).  We
extract the metal grains with a magnetic rake.  Next, we process
the metal regolith with the gaseous carbonyl process, as follows:

First phase:

Treat the regolith with CO at c. 5 atm pressure, 100 degrees
C.  This forms a vapor of gaseous carbonyl compounds.
Nickel and iron are selectively deposited in pure metallic form
by lowering the pressure and/or increasing the temperature.
The CO is released and recycled. The residue has a Pt-group
concentration of 5,000 ppm, and Ga/Ge/As at 15,000 to 20,000 ppm.

Second phase:

Treat the residue with moist CO at 100 atm near 100 degrees C.
This deposits out cobalt.  What is left is largely Pt group
and Ga/Ge/As, and is worth $20,000 per kg at today's prices.
The water and CO are again recycled.

This technique, called the gaseous carbonyl process, is currently
used at the Sudbury mine in Ontario, primarily to extract the nickel,
and secondarily to extract the c. 5 ppm platinum.  By some accounts
the Sudbury ore is actually the remains of an impacted asteroid,
but I won't get into _that_ broohaha.  :-)

If we want to get the pure elements additional processing is
required.

The method of depositing the nickel and iron can itself be put
to use.  For example, using a technique of chemical vapor deposition
(CVD) developed by Vaporform Products Inc., the nickel can be doped with
100 ppm of a boron compound and deposited in molds to obtain
nickel parts with strengths of 200,000 psi (13,000 kg/cm^2).  Laser
CVD can be used to deposit wire-reinforced mirrors a few micrometers
thick, which is strong enough to be used for very large mirrors in
microgravity.  Various forms of vacuum deposition and creation of
new alloys and foamed metal in microgravity are possible.  We have
only begun to scratch the surface in researching the possibilities.

According to a previous post, annual world production of the
platinum group is 8.668 million troy ounces, which at $400/oz. is
$3.4 billion.

It is difficult to predict the effects of flooding a market.
Generally (not always) demand volume rises by a greater factor
than prices fall, so that we can, with some risk, assume at least
a $3.4 billion/year revenue stream from the platinum group elements.
Given the demand for Pt-group metals in a wide variety of industries,
including oil refining and the rapidly growing industry of
environmental cleanup technology, IMHO this is a reasonably safe
assumption.  Assuming operating costs of $1.7 billion/year,
the net present value (NPV) of this cash flow at the junk-bond rate
of 18% is $10 billion.  Additional capabilities (GaAs, solar cells,
microgravity alloys, etc.) could provide additional revenue.  Of
course, part of the _first_ $million invested should go towards a
much more detailed market analysis this one.

Which brings us to the billion dollar question: how soon will we have
sufficient knowledge (through exploration) and technology (through
research and prototyping) to be able to undertake this projects for
less than $10 billion?


References:

_Space Resources: Breaking the Bonds Of Earth_, John and Gail Lewis
_Asteroids II_, Tom Gerhels, ed.


--
Nick Szabo                [e-mail]
"If you understand something the first time you see it, you probably
knew it already.  The more bewildered you are, the more successful
the mission was." -- Ed Stone, Voyager space explorer

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

Date: 12 Jun 91 15:11:32 GMT
From: hpl-opus!hpnmdla![e-mail]  (Stan Bischof)
Subject: Re: Excavating (minig) gold in the space by NASA.

In sci.space, [e-mail] (Ivan Maldonado) writes:

>Under the above-suggested circumstances:

>Actually, the advantages due to gold's great conductivity properties
>could also be used to significantly reduce the electric power losses during
>its transmission (i.e., replace copper with gold in transmission lines).
>===> <pooff> goes the forecast of an electric energy crisis...  :-)

>-Ivan


Only one problem--- copper is a better conductor than gold! You're
probably thinking of silver, which is indeed better than copper. Gold
is NOT a great thermal OR electrical conductor-- copper is better
in both respects, and silver is even better.

approx numbers:

  matl              thermal conductivity    elect resistivity
                      (W/cm-K)                 (ohm-cm x10-6)

  copper              3.6                      1.7

  gold                3                        2.4

  silver              4.2                      1.6

Stan Bischof
HP-NMD

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

ReSent-Message-ID: <[e-mail]>
Resent-Date:  Wed, 12 Jun 91 18:21:46 EDT
Resent-From: Tom McWilliams <[e-mail]>
Resent-To: [e-mail]
Date:         Sun, 9 Jun 91 02:06:28 EDT
Reply-To: [e-mail]
From: [e-mail]
Subject:      SPACE Digest V13 #625
Comments: To: [e-mail]
To: david polito <[e-mail]>, Tom McWilliams <[e-mail]>

Subject: Re: Privatization

>I'm kind of generally suspicious about privatization when long term research
>is in question.  Private profit driven companies seldom make plans for
>more than 5-10 years into the future.  Let's take large particle colliders
>as an example.  I doubt there would be any private organization that would
>foot the bill for CERN for instance.  Same logic can be applied to large
>space projects.

>Correct me if I'm wrong.

If your talking about R&D, your wrong.  One of the things that GM learned
from the Japanese auto-makers was to spend more on R&D for long-term health.

If your talking about Science For the Sake of Knowledge, I'd agree with you.

Tom
Acknowledge-To: <18084TM@MSU>

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

End of SPACE Digest V13 #741
*******************