Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v13_7/v13_760.txt

Internet Message Format | 1991-06-30 | 19KB

Return-path: <[e-mail]>
X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson
Received: from hogtown.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr11/tm2b/space/[e-mail] (->+dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl) (->ota+space.digests)
          ID </afs/andrew.cmu.edu/usr1/ota/Mailbox/0cPiI5u00WBwQ3S04B>;
          Mon,  1 Jul 91 04:17:10 -0400 (EDT)
Message-ID: <[e-mail]>
Precedence: junk
Reply-To: [e-mail]
From: [e-mail]
To: [e-mail]
Date: Mon,  1 Jul 91 04:17:05 -0400 (EDT)
Subject: SPACE Digest V13 #760

SPACE Digest                                     Volume 13 : Issue 760

Today's Topics:
      Re: Excavating (mining) gold in the space by NASA.
         Straw Poll for space politics newsgroup name
            Re: Beanstalk analysis reprise
                Re: Space Link
             Re: Mining El Dorado
           Re: CNN Report On Paris Airshow
              Re: A Space Science letter
              Re: anti-gravity?
                 Re: The USF.

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: 16 Jun 91 19:38:55 GMT
From: eru!hagbard!sunic!mcsun!ukc!cam-eng![e-mail]  (D.S.C. Yap)
Subject: Re: Excavating (mining) gold in the space by NASA.


>  In <[e-mail]> [e-mail] (Cray Hardware
>Support) writes:

>  Today's Washington Post reports that an asteroid has been found orbiting the
>Sun at a distance of about 20 million miles from Earth (closest point).  It
>apparently contains 10000 tons of gold and 100000 tons of platinum, as well as
>10 billion tons of iron and 1 billion tons of nickel.  Its estimated worth was
>put at around 1 trillion dollars.

>  This might be one of the first real applications of Space technology. I say
>NASA should issue stocks to built a space craft to go and bring that thing
>down.  This could open up another very lucrative investment, a side from
>satellites.  The technology we gain could help us mine other things in the
>space too.  Then, boldly going were no man has gone before makes business sense
>to.

G E Derylo replies:

>    I'm no economist, but wouldn't the introduction of that much gold and
>platinum into the market *drastically* decrease its value, making this a
>questionable financial venture? Sure, I know these materials also have crutial
>industrial applications, so we're not just dealing with jewelry here.

This is just one of many posts that come to the same conclusion about
the financial viability of a venture to mine (you wouldn't bring the
whole thing back) that asteriod.  I think it's a bit short sighted to
assume that you would want to bring that stuff back to earth so that
you could sell it on the open market.  Hell, it's damn expensive to
get that stuff up there in the first place, both in terms of energy
and money.  There are some things that can only be manufactured in
microgravity, but in any manufacturing process you need raw materials
- it's nice to know there's lots up there, not too far away.

If anyone is seriously considering going out to fetch it, "Have I got
a solar sail for you!" :-)  It's the perfect thing, it's smart
(semi-automatic, adaptive control), never needs refueling, will
shuttle back and forth from the asteriod in practical time frames, and
if you're serious, we can have one ready for you in two to three years
(or less - best estimates are ten weeks to actually build one, but the
design is still underway).  "Guess what?", I'm not kidding.  Oh yes,
the price, say $40M for the first one, much less for subsequent ones
(but that's just a rough guess on my part, you can't hold me to it
because I'm not in charge - I'm just working on the structural
dynamics of the beast - the powers that be probably want to make a
profit, besides, I'm just posting for fun - this is not an ad).  Of
course, that price is without launch.

Cheers,

Davin
--
          .oO tuohtiw esoht fo noitanigami eht ot gnihton evael Oo.
      Davin Yap, University Engineering Department, Cambridge, England
                       -->  [e-mail]  <--

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

Date: 18 Jun 91 18:42:33 GMT
From: eagle!ariel.lerc.nasa.gov![e-mail]  (Ronald E. Graham)
Subject: Straw Poll for space politics newsgroup name

I am conducting a straw poll for a name for a proposed new group to
cover space politics issues.  The charter has been posted under threads
related to the originally-proposed talk.politics.space.  There are two
other names for this proposed group that have support, each having a
different placement in the hierarchy.  Here is how I propose the straw
poll be conducted:

o  send your $0.02 via e-mail to me and I will summarize;
o  send me your order of preference if you have one, or a single vote
   if you only care about one name/placement;
o  send me your concern if you are violently opposed to any name, so
   that I can enter your concern into the summary.

I will score the straw poll as follows:

     2 points for first choice
     1 point for second choice
     0 points for third choice or opposition

The three names under consideration by posters are

     talk.politics.space
     sci.space.policy
     misc.activism.space

And I will summarize this in a week.  Please note: this is not a Usenet
Call for Votes - no group is to be formed as a result of this poll.  It's
just to determine under what name a group is to be formally proposed.

RG

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

Date: 18 Jun 91 15:31:52 GMT
From: cis.ohio-state.edu!zaphod.mps.ohio-state.edu!mips!ptimtc!nntp-server.caltech.edu!sol1.gps.caltech.edu![e-mail]  (Carl J Lydick)
Subject: Re: Beanstalk analysis reprise

In article <[e-mail]>, [e-mail] (Ron Carter) writes:
>The terminal velocity of a cable of density 1.7 must be
>considered.  If the cable is only an inch or two in diameter
>and the lengths are not long enough to whip the ends up to
>high speed ("range-safety" equipment is indicated!), terminal
>velocity will not be high, and damage will be small.

I don't think I've heard of any beanstalk proposal that has a cable "only an
inch or two in diameter".

On another note:  A couple of years ago, somebody (Robert Forward, maybe?)
published a fairly detailed study of what it would take to make a beanstalk in
a fact article in Analog Science Fiction/Science Fact.  As I recall, the
conclusion was that if our knowledge of how chemical bonds work is correct,
there is theoretically no material strong enough for a beanstalk anchored to
the Earth (to Mars or the Moon, yes; to the Earth, no), but that pinwheels
would be possible.  Anybody out there with that issue of Analog?
--------------------------------------------------------------------------------
Carl J Lydick | INTERnet: [e-mail] | NSI/HEPnet: SOL1::CARL

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

Date: 18 Jun 91 17:37:05 GMT
From: agate!spool.mu.edu!caen!uakari.primate.wisc.edu!news.arc.nasa.gov!cincsac.arc.nasa.gov![e-mail]  (Milo S. Medin)
Subject: Re: Space Link

In article <[e-mail]>, [e-mail] (Jeff W. Hyche) writes:
...


|> HOW
|> NASA/Spacelink reaches the Internet via the Southeastern Universities Research
|> Association Network (SURAnet), a regional network affiliated with National
|> Science Foundation Network (NSFNET).
|>
|> FUTURE
|> NASA/Spacelink's next expansion phase will increase several elements of the
|> system, including additional storage for images from NASA's observatories.
|> NASA/Spacelink's Internet connectivity will be upgraded to offer more
|> simultaneous TELNET sessions and FTP file transfers.
|>

Not quite.  MSFC is not connected via SURANet, but in fact the NASA Science
Internet (NSI), which connect MSFC and the most of the NASA Centers and NASA
Science facilities in the US and abroad.  We fully cooperate with the other
agencies in the US who do networking, so by and large, all our sites are fully
routable to the Internet as a whole, though some sites implement access
controls locally for security reasons.  No NASCOM or mission critical communications facilities are interconnected to the science networks, so
don't even try breaking into the mission control facilities; they are fully
isolated from the science and research communications systems.

Also, the Spacelink computers do not speak TCP/IP per se, but are connected
via async RS232 through terminal servers, and that's why they don't grok FTP.
At least that's the way it used to work.  Assuming they can get TCP/IP support
for their DG system running AOS, then you should be able to get full internet
services.  Most of the SpaceLink data is available for FTP from ames.arc.nasa.gov, which archives a lot of NASA stuff.  You can also access it via
Telenet, if you have an access code and password (direct Telenet access to
NASA X.25 resources is restricted in most cases).


                        Thanks,
                           Milo Medin

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

Date: 17 Jun 91 05:22:28 GMT
From: cis.ohio-state.edu!zaphod.mps.ohio-state.edu!mips!cs.uoregon.edu!ogicse!sequent!muncher.sequent.com![e-mail]
Subject: Re: Mining El Dorado

In article <[e-mail]> [e-mail] (Charles (from bbs)) writes:

>We do not want lots of fragments flying everywhere, all we need
>is to create a powerful shock wave to disrupt the asteroid structure.
>The shock should be small enough that gravity will continue to hold
>the pieces together.   We could literally surround the asteroid with a
>safety net to ensure most of it is retained.

Any significant shock wave is going to be greater than the escape velocity
(a few m/s).  The net, perhaps nylon, is a better idea.  Also, if
possible set up the explosive(s) so that they fracture the insdide
of the asteroid while leaving a surface shell intact.  (Charles suggests
this also later in his post).  The combination of the net and the shell
may be sufficient.

Cold metal is brittle, but I am not sure whether it would fracture in
the way we like, rather than just melting and recondensing.  Data from
underground nuclear explosions would help here.  It would be best
if we could produce powerful ultrasound with little heat.


>pieces can be individually transported or processed by a robot
>smelter.

Pumping a very thin atmosphere, and/or magnets may suffice to move
the gravel through tubes in microgravity.


>In the immediate term it would be interesting to send a probe to
>El Dorado,  to see if it is differentiated or homogoneous.

It is mostly likely homogoneous, I am afraid.  The metal asteroids
that have struck earth (iron meteorites) are homogenous.

Another interesting thing we need to know is how much metal regolith
exists on the surface.  This saves us the blasting and grinding steps.

In general, exploration is cheaper than mining, and we should
search widely to discover the most easily extracted resource before
committing $billions to mining projects.


>thermonuclear shaped charge could be inserted into the interior of El
>Dorado, and the drill hole widened.   The blast would then be mostly
>directed out through the vent hole, creating a more substantial thrust
>reaction, which could maybe manouver El Dorado within a few million
>miles of Earth.

Some issues here:

* We can't use Earth gravity assist or aerobraking for such a large
  asteroid and unpredictable propulsion scheme.  Therefore, the delta-v
  is likely to be quite large (several km/s).

* The energy required to achieve that delta-v would likely disrupt or
  vaporize the asteroid.  For example, to achieve 4,000 m/s the power
  output is (1e10 kg)(4,000 m/s)^2/(.01 s) = 1.6e19 watts assuming a
  propogation time of .01 second.  Of course, we could do multiple
  explosions, but hundreds to thousands of small nuclear warheads starts
  to get expensive.

* The Christic Institute et. al. don't like things called "nuclear".  There
  is also a treaty that ban putting nuclear explosives in space which
  would have to be changed (this is a good idea anyway -- it would be much
  better to allow nuclear explosives in space and ban them on Earth!)

Interesting brainstorm.



--
Nick Szabo            [e-mail]
Embrace Change...  Keep the Values...  Hold Dear the Laughter...
These views are my own, and do not represent any organization.

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

Date: 17 Jun 91 08:11:04 GMT
From: eru!kth.se!sunic!mcsun!corton!irisa!irisa.fr![e-mail]  (Henry Thomas)
Subject: Re: CNN Report On Paris Airshow

In article <[e-mail]>, [e-mail] (John A. Weeks III) writes:
|> CNN Headline News had a blurb on the Paris Airshow tonight.
|> I thought I would pass on what I caught of the report.
|> [...]
|>
|> Hermes mock-up on display.  Mir mock-up.  CNN also filmed some
|> type of multi-nation (non-US) space hardware that I did not catch--it
|> looked like a space station and I think they called it the Columbus.
|> Anyone know what I might have seen?

Colombus is the european module which should be connected to the space station freedom. And Hermes would enable european astronauts the access to such module, independently of the american fancyness.

|>|US military aircraft are on display complete with US troops.
|>Planes shown on the video include the F-117A 'Stealth Bomber',
|>F-14 Tomcat, A-10 Warthog (complete with kill stats painted on
|>the nose), F-15 Eagle, and the AH-64 attack chopper.  (It seems
All these bombers have a stick on them : "Proved in combat". Is there a stick on the victims "Tested in combat" ?
|>[...]

--
Henry Thomas - IRISA          - E-mail: [e-mail]
Campus Universitaire de Beaulieu - Phone: [phone] +549
35042 RENNES CEDEX FRANCE      - Fax: [phone] Telex: UNIRISA 950473F
Telex Atlas X400: /X121=842950473/@atlas.fr, Fax:/X121=200099383832/@atlas.fr
--

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

Date: 18 Jun 91 01:50:02 GMT
From: snorkelwacker.mit.edu!usc!zaphod.mps.ohio-state.edu!caen!ox.com!hela![e-mail]  (Allen W. Sherzer)
Subject: Re: A Space Science letter

In article <[e-mail]> [e-mail] writes:

>Congress has to cover a wide range of topics including DoD, DOE,
>Commerce, Agriculture, EPA, etc. etc.  It cannot be expected to understand
>details of planetary missions, any more than a rocket engineer can be
>expected to be well-versed in tort law.

Nonsense. Congress has an entire subcommittee devoted to nothing but space.
This includes a dozen or so Congresscritters, their staff, the majority
subcommittee staff, the minority subcommittee staff, and part of the full
committee staff for the majority and minority. In the House the head of the
full committee (Rep. Brown) is very interested in space and devotes
significant time to it. Members may call on one of several research
services to address specific questions.

This subcommittee (in both houses) set a series of priorities for NASA
funding. These priorities where then endorsed in both houses by a wide
margin.

>It is up to the NASA leadership to
>provide an intelligent budget and guidance on these issues.

Of the people I talk to none trust NASA further than they could spit a rat.

>On this topic, is there any way for space explorers to transfer
>money "under the covers" to provide the funds where they are needed?

It has already happened. Space explorers in both NASA and the DoE have
scraped together a few million to do the work needed to support a
cost effective human infrastructure. If some new line items survive
in the DoE budget we will see even more.

    Allen
--
+---------------------------------------------------------------------------+
|Allen W. Sherzer |   DETROIT: Where the weak are killed and eaten.         |
|   [e-mail]   |                                                         |
+---------------------------------------------------------------------------+

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

Date: 18 Jun 91 22:57:59 GMT
From: cis.ohio-state.edu!zaphod.mps.ohio-state.edu!usc!snorkelwacker.mit.edu!news.media.mit.edu!media-lab.media.mit.edu![e-mail]  (Marvin Minsky)
Subject: Re: anti-gravity?

In article <[e-mail]> [e-mail] (Brett Kottmann) writes:
>
>    A researcher in Scotland has developed a device that harnesses
>gyroscopic energy to lift a device against gravity--antigravity...
>
>    In demonstrations, the apparatus lifts against gravity (it is balanced
>beforehand with an equal weight via balance arm).

Well, this is good for a contest.  Balances are easy because one can
make the required lift arbitrarily small.  So you can use

   a surreptitious airflow
   how 'bout running current through an electromagnet fied along the
balance arm.  this will produce torque in the earth's field.  (Called
a "dipping needle".
   simply putting a few KV of DC between the hardware and the balance
is almot sure to deflect the beam one way or the other, unless the
environment is symmetrical.

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

Date: 19 Jun 91 00:02:54 GMT
From: prism![e-mail]  (Matthew DeLuca)
Subject: Re: The USF.

In article <[e-mail]> [e-mail] (Tarl Neustaedter) writes:

>Given that this group is arrogating to itself the authority to "draft and
>enforce international space law", I think detailed scrutiny of the current
>organization, it's funding and official backing, is very much in order. Any
>law-writing/enforcement organization needs continual monitoring of who and
>what controls it; sources of funding are the primary means of such monitoring.

Fortunately, anyone can write all the laws they like...getting someone
to *enforce* those laws is something else entirely. :-)  The 'USF' will
quietly fade away in a few months, like most other self-styled space
agencies.

--
Matthew DeLuca
Georgia Institute of Technology      "I'd hire the Dorsai, if I knew their
Office of Information Technology      P.O. box."  - Zebadiah Carter,
Internet: [e-mail]    _The Number of the Beast_

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

End of SPACE Digest V13 #760
*******************