Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V16_3/V16NO381.TXT

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Date: Mon, 29 Mar 93 05:00:10
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #381
To: Space Digest Readers
Precedence: bulk


Space Digest                Mon, 29 Mar 93       Volume 16 : Issue 381

Today's Topics:
  better planets through nanotechnology (was Re: How to cool Venus)
                       Coral and Dyson Sphere..
                       GPS/SEDS-1 Launch Window
Gravity waves, was: Predicting gravity wave quantization & Cosmic Noise (2 msgs)
                     Making Those Venusian Oceans
                           mars coordinates
               Orbital Skysurfing Club/DTO... (2 msgs)
Speculation: the extension of TCP/IP and DNS into large light lag enviroments (4 msgs)
                           SSF Redesign....
               Terraformers (was Re: How to cool Venus)
                          Terraforming Venus
           the call to space (was Re: Clueless Szaboisms )
                     Venus is covered with water?
                         Why is Venus so bad?

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Date: 28 Mar 93 16:43:37 GMT
From: "David M. Palmer" <[e-mail]>
Subject: better planets through nanotechnology (was Re: How to cool Venus)
Newsgroups: sci.space

The big problems with living on Venus are the atmosphere (pressure
and composition) and the temperature.

One way to terraform Venus is through the miracles of nanotechnology.
Nanotechnology is the sufficiently advanced technology (in the Clarkian sense)
of molecular-scale machines.  See Drexler's books ("The engines of
Creation", "Unbounding the future", "Nanosystems") for more details.

[e-mail] (Del Cotter) gives the composition of the atmosphere:

>Gas        Volume            Mass/kg
>CO2        96.5%            4.60e20
>N2         3.5%            1.06e19
>SO2        200 ppm            1.40e17
>Ar         70 ppm            3.40e16
>CO         40 ppm            1.17e16
>Ne         10 ppm            1.09e15
>H2O        100-1000 ppm?        0.19-1.86e17

Most of the proposals for converting the atmosphere to something breathable
have concentrated on blowing it off into space.  However, there is
a way to bind this atmsophere into solid form and deposit it on
the surface of the planet, if you do not require that this be done
with simple equilibrium chemical reactions.

Once you have nanotechnology at a fairly low level (2 decades to eternity
from now, depending on your optimism level) you can design a nanomachine
which makes a hollow diamond shell out of the carbon in the CO2 in the
atmosphere, and then fills it with atmosphere at high pressure.
The shell is then allowed to drop to the surface, and the nanomachine
repeats the process.

Once the air is thin, a sunshade at L1 can rapidly cool of the
atmosphere.  The ground will take longer to cool, but it
is easy (using the word 'easy' in a sense you have probably not
encountered before :-) to program the nanomachines to lay
down a layer of insulation (maybe a few meters of
low density graphite-vacuum foam) before putting down
arable soil on top.  This will let people move in
almost immediately, although they will not want dig
very deep.

The Pressurized gas in diamond (PGID) could be used as a rocket fuel.
The specific impulse would depend on (among other things) the
internal gas pressure.  Unfortunately, I don't know the tensile
strength of diamond, so I can't calculate that.  (Actually,
diamond's tensile strength is a lower limit.  Since a pressure
vessel need be strong only in 2 dimensions, rather than 3,
you can probably boost the strength somewhat.)

I suggest that we wait fifty years or so to see whether nanotech
will get us a quick way to terraform Venus before we try the
more conventional, slower techniques which have been discussed.

--
        David M. Palmer        [e-mail]
                    [e-mail]

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

Date: 28 Mar 93 15:20:46 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Coral and Dyson Sphere..
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:
>So I am wierd..

No argument. :-)

>How to get the coral to build the "reef" in the shape wanted??

More importantly, what are you going to *feed* the coral organisms?
At a minimum they're going to need N,P,K,O,C, and Ca, all in a form
they can organically process, plus plenty of H2O as a carrier.

What are you going to use to *anchor* the first segments? Coral grows
against a gravity gradient toward nutrient and energy rich sources.

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: Sun, 28 Mar 1993 08:30:15 -0500
From: Alan Kirschbaum <[e-mail]>
Subject: GPS/SEDS-1 Launch Window
Newsgroups: sci.space

Dean Adams asks:

 >* Mar 27 - GPS/SEDS-1 Delta II Launch
 >Does anyone know the LAUNCH WINDOW times for this flight?

The flight was delayed one day due to 1st stage motor commonality
with last week's Atlas launch failure.
The launch window for Mar 28 is 10:13pm to 10:41pm, EST.

Look to the Northeast, if you happen to be at my house.


 * Origin: 1.L.C. BBS: Source For Information! 407-676-2998 (1:374/60)

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

Date: Sun, 28 Mar 1993 09:32:17 GMT
From: Dave Kipfer u <[e-mail]>
Subject: Gravity waves, was: Predicting gravity wave quantization & Cosmic Noise
Newsgroups: sci.space,sci.astro,sci.physics,alt.sci.planetary

Nick Haines ([e-mail]) wrote:
: In article <[e-mail]> [e-mail] (SCOTT I CHASE) writes:
: Simple: you measure the area or circumference of a circle. You can
:
:   the surface is flat. Likewise, if the ratio of the circumference to
:   the diameter is pi, the surface is flat. If these are less than pi,
:   the surface is positively curved (like a sphere); if they're more
:   than pi then it's negatively curved (like a saddle). (If one is more
:   and the other is less then you've fouled up your measuring).
:
:   Remember, pi is not defined here by using circles, but as the limit
:   of some number-theoretic series. If your ant civilisation doesn't
    I don't quite see how you expect to differentiate between the curve of
the surface being concave or convex.  In particular, take the circle that you
drew on the surface which is curved upwards.  Now, considering this surface
to have negligible thickness, take a look at this circle you drew from the OTHER
side, which will be curved DOWNWARDS.  Now, it's the same circle, right?  So,
it would be obvious that it has the same circumference, correct?

    The test I have been accustomed to for figuring out the curvature of a
surface is to draw a triangle on the surface, and measure its angles.  If we
are on a flat (Euclidean) surface, the sum will be the famous 180 degrees.
If we draw it on a surface curving downwards, it will have less than 180
degrees, and, if drawn on a surface curved upwards, we will have more than
180 degrees.  It is a rather simple situation to visualize.

    Just my thoughts...

--
Dave Kipfer                      |  FidoNet: 1:221/204   DragoNet: 9:519/100
Wilfrid Laurier University       | -Excuse me, I have to recharge my
Waterloo, Ontario, Canada        |  flamethrower.
Internet: [e-mail]  |  These are my opinions, not those of WLU.

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

Date: 28 Mar 93 16:25:55 GMT
From: Bruce Scott <[e-mail]>
Subject: Gravity waves, was: Predicting gravity wave quantization & Cosmic Noise
Newsgroups: sci.space,sci.astro,sci.physics,alt.sci.planetary

"Downward" and "upward" curvature are not intrinsic functions. These can
be defined only with respect to an embedding space of higher dimension.

What does matter is the sign of the curvature. This can be found by
measurement of areas and circumferences (or the higher-dimensional
analogs thereof). The difference between positive and negative curvature
is not that between "upward" and "downward": the shape of the surface
differs. It is the difference between a spherical surface and a saddle
surface in the case of 2D isotropic spaces.

Gruss,
Dr Bruce Scott                             The deadliest bullshit is
Max-Planck-Institut fuer Plasmaphysik       odorless and transparent
bds at spl6n1.aug.ipp-garching.mpg.de                 -- W Gibson

--
   The opinions expressed are not necessarily those of the University of
     North Carolina at Chapel Hill, the Campus Office for Information
        Technology, or the Experimental Bulletin Board Service.
           internet:  laUNChpad.unc.edu or 152.2.22.80

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

Date: Sun, 28 Mar 93 13:01:58 EET
From: [e-mail] (F.Baube[tm])
Subject: Making Those Venusian Oceans

Someone suggested importing hydrogen to get

    CO2 + 4 H -> C + 2 H2O

Well, gee, the *Sun* has lots of hydrogen
floating around free for the asking ..

How to get it from Point S to Point V ?

--
* Fred Baube (tm)         * In times of intellectual ferment,
* [e-mail]       * advantage to him with the intellect
* #include <disclaimer.h> * most fermented
* May '68, Paris: It's Retrospective Time !!

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

Date: Sun, 28 Mar 1993 18:34:10 GMT
From: Frank Crary <[e-mail]>
Subject: mars coordinates
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Steve Collins) writes:

>I heard recently that there have been several "official" prime meri{dians
>for mars{.

It's possible: There are at least three meridians in use for Jupiter.

>...Does anyone know if this is true and if so, whether the
>prime meridian (or pole) has moved a long ways from the current
>(IAU ?) location?

But I've only seen the IAU 1971 standard meridian in use for Mars. If
there are others in use, they are either very similar or not commonly
used...

                                                       Frank Crary
                                                       CU Boulder

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

Date: 28 Mar 93 15:26:36 GMT
From: "David M. Palmer" <[e-mail]>
Subject: Orbital Skysurfing Club/DTO...
Newsgroups: sci.space

[e-mail] writes:

>> In article <[e-mail]>, [e-mail] writes:
>> |> Anyone want to start a Skysurfing Club,

>One of the basic ideas to be used is an asbestos "surfboard" and a man/woman in
>a space suit.. Some form of manuvering jets and away we go, now to get into
>orbit..

People already do skysurfing, but from airplane rather than orbital
altitudes.  I've seen several ads on TV showing somebody doing it.
(The ads were for lifestyle products, like beverages or shoes.)

--
        David M. Palmer        [e-mail]
                    [e-mail]

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

Date: Sun, 28 Mar 1993 20:07:18 GMT
From: Tom A Baker <[e-mail]>
Subject: Orbital Skysurfing Club/DTO...
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (David M. Palmer) writes:
>[e-mail] writes:
>
>>> In article <[e-mail]>, [e-mail] writes:
>>> |> Anyone want to start a Skysurfing Club,
>
>>One of the basic ideas to be used is an asbestos "surfboard" and a man/woman in
>>a space suit.. Some form of manuvering jets and away we go, now to get into
[BLOCK MOVE]
>People already do skysurfing, but from airplane rather than orbital
>altitudes.  I've seen several ads on TV showing somebody doing it.
>(The ads were for lifestyle products, like beverages or shoes.)

I've reacted positively to this idea, as a very long-range thing.
For instance ...

[BLOCK MOVE]
>>a space suit.. Some form of manuvering jets and away we go, now to get into
>>orbit..

... I assumed you would start in orbit.  That is, some folks in LEO would
strap on a big board, and somehow get into a trajectory that intersected
with the atmosphere.  You dip in, do acrobatics, but you probably skip
back out again, where you re-assume orbit.  (Either you had a rocket all
along for that purpose, or your friends rendezvoused with you in a quarter-
or half-orbit and boosted you.)

The attraction is the same as for those who skysurf by dropping out of
airplanes.  Only the speed is 17000 mph faster, and the view ....

(Hmm, I was going to say that the view was 90 miles higher.  But if you
start in orbit, I would say any view results from getting tens of miles
*lower* than that.)

tom

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

Date: 28 Mar 1993 07:02:45 -0500
From: Paul Robinson <[e-mail]>
Subject: Speculation: the extension of TCP/IP and DNS into large light lag enviroments
Newsgroups: alt.internet.services,sci.space

M. Sean Bennett ([e-mail]) wrote:
: As man moves outward into space it will become essential to provide an
: information structure for communication of data.

I got thinking about this myself.  Humanity must expand beyond the planet
earth and out to the stars, because this planet is not going to be able to
support unlimited breeding forever.  If human beings are to survive,
outmigration *must* occur.  This will then lead to a whole new set of
problems.

:     The current set of protocols make no alowance for light 'lag' between
: targets of wide divergence. (Mars-Earth). The current DSN is expensive to
: use for continous data flow. If however we could use a series of store and
: forward systems for data - we have no mechanism to ensure that the data is
: delivered securely (Appart from ad-hoc protocols constructed by NASA).

I would suggest something on the order of a "continuous transmission
channel" concept using something akin to ZMODEM with patch retransmission,
indexing and table of contents.

Patch retransmission means that after I transmit a 2 billion byte file,
you may ask me, two days later, to retransmit the blocks from 100,000 to
120,000 bytes, 2,030,140 to 2,303,140 bytes, and perhaps 50 or 60 other
places where noise damaged the file.  Or the file can be transmitted
multiply in sections, or other such things.  But the file would have to be
available the entire time of round trips, plus communications delays.

One consideration is the "IHAVE" / "SENDME" protocols in news; as a file
is received, the other side sends back lists of files it has gotten okay
until the other side confirms that it has received the okay, like this.

Earth: "At 21:00  file 31032.33307, time 00:10
        At 21:11  file 31032.33308, time 00:20
        Confirm receipt youhave 31030.00401
        Confirm receipt youhave 31030.00403..."

Mars:   Retransmit file 31031.01202 block 401
        Retransmit file 31031.01202 block 402
        I HAVE 31031.01203
        I HAVE 31031.01204
        Retransmit file 31031.01202 block 403

And so on, probably both sending on different channels.

:     We need some form of ISO standard (I know they are hard to set,
: but if NASA/GlavCosmos publish a protocol it will be the defacto standard)

If it deals with Internet, the correct place is in the Internet RFCs.
A good idea would be to propose a mailing list to handle the ideas and
pass things around beforehand.  Or send out an RFC for the purpose of
soliciting the standards.

:     How are we to devide the domains to deal with other worlds?

If a domain is not directly related to a specific place, it can be on
the .COM, .EDU, .ORG or .NET domains for Commercial, Educational,
Organization, or Network sites.  There is also an .INT domain for
international organizations (replaces the old .NATO) domain.  I'll mention
the .GOV domain below.

For "countries" outside of earth, the domain name table for specific
countries consists of a two-letter code.  Now, all of the combinations of
two letters (AA-ZZ) is 676 areas.  Also the codes can be changed to allow
codes consizsting of a digit and a letter, such as  "domain.3x"
That would add another 260 domains.  In fact, that might be better, i.e.
non-earth domains would be a digit and a letter.

:         (yes I know this sounds mad - but if we have not made some
:     form of descision we will have moonbase.nasa.gov - implictly
:     making that instalation part of the USA..a dangerous precedent)

I don't think the .GOV domain is explicitly U.S. Government, but I can't
guarantee that.  I know that some states use the .GOV domain (OHIO.GOV is
one, but as to whether or not other countries do, it's probably that they
prefer their own country code).

: These are just my random thoughts. I make no claims that they hold great
: thought or meaning.

:     [e-mail]

I'd rather stick with the 2 and 3 letter codes.   They are having a hard
enough time getting rid of the .ARPA domain as it is.  Some software isn't
designed for 4-letter domains.   And I'd rather see short names than long
ones.

Also, it would require going to something other than TCP/IP for a
transmission protocol.

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

Date: 28 Mar 1993 07:08:44 -0500
From: Paul Robinson <[e-mail]>
Subject: Speculation: the extension of TCP/IP and DNS into large light lag enviroments
Newsgroups: alt.internet.services,sci.space

Tom A Baker ([e-mail]) wrote:
: In article <[e-mail]> [e-mail] (M. Sean Bennett) writes:
: >As man moves outward into space it will become essential to provide an information
: >structure for communication of data.
: >
: >    The current set of protocols make no alowance for light 'lag' between
: >targets of wide divergence. (Mars-Earth). The current DSN is expensive to

: Now hold on there.  Even terrestrial protocols take notice of "lightspeed
: delay".  And transmissions over satellite links in the Clarke orbit
: require special parameters for their error correction protocols.  They
: don't use XMODEM or Kermit; there is something like a 570 mS round trip
: time, so the handshaking is arranged with that in mind.

: >    We need some form of ISO standard (I know they are hard to set,
: >but if NASA/GlavCosmos publish a protocol it will be the defacto standard)

: I do think we will indeed have a standard, when the need arises.  Until
: that time, we will have to wait to learn of the resources available then.

: I for one would be tickled pick if we could set up optical fiber cables
: between the two planets.  And don't say that is flatly absolutely
: impossible.

But I would rather dread trying to run a wire 60 million miles, even if
you use relays.  How much would it cost to spin 60 million miles of fiber
optic cable from, say, the Moon to Mars, plus the cost of booster
stations, plus the (rare but possible) chance of meteor collision across
the particular wire.

You've got vacuum out there, you can just *pump* the light directly from
spot to spot.  Use directional microwave or lasers; but don't go sending
solid wire all that distance.  Of course, you could use both, or use
multiple transmission paths.

This is such an interesting idea that I think it's worth discussing.

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

Date: 28 Mar 1993 11:53:22 GMT
From: "M. Sean Bennett" <[e-mail]>
Subject: Speculation: the extension of TCP/IP and DNS into large light lag enviroments
Newsgroups: alt.internet.services,sci.space

Now of course point-to-point with optic fiber is not possible - as the targets move

The beauty of optic fiber is its that you minimise evesdroping possibilities.

Now imagine this:

    {We need skyhook material - thanks jerry}

    First we relocate some asteroids to some mid Earth-Mars orbit, link them together
with skyhook stuff and run optic-fiber along the entire length with routers every 10%
of the cable.

    Next we build a cascade of spining skyhooks, A skyhook rotating against its
direction of motion a few 100km long.

    Now every so often the lowest of these would dip one tip into the atmosphere to
the hight of 10km altitude - moving ground relative v.slowly .

    At that point we would do a point to point laser transfer.

    This data would be stored - then transfered to the next highest orbit until it
reached the L1 point (Langrange point narest earth) where it would be transfered to L1
then via a skyhook cable to the luna surface,across to the far side of the moon and up to
the luna farside Langrange point (L2).

    We then have a series of spining solar orbit skyhooks that just touch L2 and the
solar cable.

    You reverse the procedure down to the MARS surface.

    Keeping this mess in line, dealing with accidents and problems -would be a
major task. The real reason you would build this set up would be to drop your travel
times for non-cyberspace objects. You could reach the moon in a few hours (faster if
you build a true skyhook) Mars within a week (faster if the target is inanimate).

    So we could >>almost<< give you point to point and only for brief moments.

Sean

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

Date: 28 Mar 1993 07:16:43 -0500
From: Paul Robinson <[e-mail]>
Subject: Speculation: the extension of TCP/IP and DNS into large light lag enviroments
Newsgroups: alt.internet.services,sci.space

Phil G. Fraering ([e-mail]) wrote:
: [e-mail] (M. Sean Bennett) writes:

: >>Why is it a dangerous precedent? Should NASA or the CIS be building bases
: >>that aren't under any jurisdiction?

: >It is my fault for not making myself clearer.

: >The Moon, Mars, etc. are "claimed for all mankind".

: >The dangerous precedent is the exporting of our national bigotries - irespective
: >of the nation involved.

: It's not really dangerous; what _is_ dangerous, is the regime you outlined
: above, which was implemented by the COPOUS Treaty.

: >What is this COPOUS treaty you speak of?

: A treaty that gave space "to all mankind;" literally, it gave _any_ nation
: on the face of the earth veto power over anything done by anyone up there.

: The death-squad-installed presidents of Honduras or Cuba would have
: just as much say in being able to stop space exploration as the
: heads of state of any other countries. In short, space exploration
: becomes even more of a hostage to tyrranical politicians, wheras
: in my opinion (which I do not think is humble, but is as close to
: absolute truth as humans get) it should not be hostage to any politicians
: at all.

Only to the extent that (1) someone is from a country that signed the
treaty and (2) that there is local law giving some organization the
authority to enforce the treaty provisions.  If someone starts their own
country (and in theory you could do it with a combination of buying some
unused island and bribing some other country for recognition) then this
piece of paper has no jurisdiction there, either.

And, further, a treaty is only binding on the government that signs it; a
government can force people to comply with some treaty, but it has no
authority to bind non-signatories to it.  For example, it is a violation
of the Moscow Treaty of 1964 to fire thermonuclear weapons above ground,
by the signatory governments.  This does not apply to non-governmental
parties.

And then it would only be effective to the extent that some organization
was on earth.  Once someone got off earth, local governments would have no
jurisdiction.  (Where are their transports to send troops?)

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

Date: 28 Mar 1993 18:16:53 GMT
From: Dave McKissock <[e-mail]>
Subject: SSF Redesign....
Newsgroups: sci.space

Note that Hugh's comments are only for the *ONE* option the
Shea team is looking at. Yes, the existing SSF program took our
suggestions to the Shea team, but we were only one of many
options the Shea team is looking at.

Also, it seems to me that we (the existing SSF team) have a bit
of a credibility problem relative to projected costs of the
"redesigned" SSF. Just weeks ago, our Associate Administrator
(Aldrich) reported to congress that part of the cost overrun
was due to poor estimates of the impact of the last redesign.
It seems to me a rather obvious question is "What confidence
does NASA have in the new cost estimates for the redesigned
SSF?" I also think the Shea team has a difficult task in
coming up with credible cost estimates for all of the wild
ideas floating around, in a 3-month timeframe.

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

Date: 28 Mar 93 11:19:21 GMT
From: Del Cotter <[e-mail]>
Subject: Terraformers (was Re: How to cool Venus)
Newsgroups: sci.space

<[e-mail]> [e-mail] (William Reiken) writes:
>
>    Hey you guys, I am posting a question about Venus.  I would like
>to know:
>
>    ""What is the total composition of the Atmosphere of Venus?""
>
>    That means every little element, etc. ever detected in its Atmosphere.
>If you can give me the percentage ratios that would also be very welcomed.

Gas        Volume            Mass/kg
CO2        96.5%            4.60e20
N2         3.5%            1.06e19
SO2        200 ppm            1.40e17
Ar         70 ppm            3.40e16
CO         40 ppm            1.17e16
Ne         10 ppm            1.09e15

H2O        100-1000 ppm?        0.19-1.86e17

Refs.

G Schubert and C Covey 'The Atmosphere of Venus'
from 'The Planets' pp. 16-25
published by W H Freeman and Co., San Francisco (1983)
--
 ',' ' ',','  |                                                  |  ',' ' ',','
   ', ,','    |       Del Cotter       [e-mail]      |    ', ,','
     ','      |                                                  |      ','

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

Date: Sun, 28 Mar 1993 13:03:35 GMT
From: Paul Dietz <[e-mail]>
Subject: Terraforming Venus
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (John Roberts) writes:

> As you wisely point out, it's vitally important to try to plug in actual
> numbers to see if the idea makes any sense at all. I seem to have taken the
> results offline from the last time the math was worked out, but it came out
> as a really ridiculous expenditure of effort - the hydrogen bomb to do the
> job would make a pretty respectable moon. Paul Dietz may still have the
> calculations.

Let's do the computations.

Venus's atmosphere has a mass of about 5e20 kilograms.  Escape
velocity is about 1e4 m/s, so at least 2.5e28 J is needed to eject the
atmosphere.  Only a small fraction of this gets lost to the crust, if
we do it right: the pressure increase in the heated atmosphere
(ignoring brief peaks) will only be on the order of several hundred
bar, and the temperature increase, while large (in the tens of K) will
no affect much rock, as rock is a very poor conductor of heat.  Loss
of energy to thermal radiation to space is also negligible.  Probably
the largest losses would be nonuniform ejection of mass to space, and
dissociation/ionization in the gas (but much of that gets recovered as
the gas expands and cools).  Multiple by a factor of several if you
want to eject the mass out of the solar system.

What fuel would the bombs use?  (Note that I say bombs, as a single
bomb would not uniformly heat the atmosphere.)  Let's assume deuterium
for the moment.  Deuterium reacts with itself via two reactions; one
making 3He, the other tritium.  The tritium is promptly consumed,
releasing a neutron.  In a sufficiently large mass of fuel the neutron
will be captured.  The net reaction will approach d + d --> 4He +
energy, with some energy lost to the net side reaction d -> p + n.
Let's call the net energy release 10 MeV/deuterium nucleus.

2.5e28 J would then require the fusion of about 50 billion tonnes of
deuterium, which, as a liquid, would make a sphere about 9 km in
diameter.  At $2M/tonne, this would cost about 100 quadrillion
dollars.  Adequate deuterium should be available in the outer solar
system, although it would require in-situ processing of on the order
of tens of trillions of tons of hydrogen.  Perhaps floating
ammonia/hydrogen isotope exchange factories in Jupiter's atmosphere
could be used.

One source of deuterium is Venus itself, where the D/H ratio is
about 100x larger than elsewhere in the solar system.  But I
don't believe there's enough there, by itself.

Deuterium does produce neutrons, and requires isotope separation.
Perhaps a better fuel would be p + 11B.  This requires no isotope
separation (11B is the dominant isotope).  On the other hand, boron is
much less common than hydrogen.  The boron in the earth's oceans would
more than suffice.  More fuel would be required -- this reaction
liberates about 8 MeV -- but the fuel is more dense, and essentially
aneutronic (and the minor 10B will soak up neutrons that are
produced).  Some cheap way of separating out the boron would be
required (say, by bioengineering?).  If Mars once had oceans (or, if
Mars is terraformed first), perhaps borate deposits will occur there
in sufficient quantity.

If it can be made to work, reactions involving protons with carbon,
nitrogen or oxygen would be best.  But these go at low rates, due
to the high coulomb barrier and (for the dominant isotopes) the
inherent slowness of (p,gamma) reactions.

    Paul

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

Date: 28 Mar 93 15:12:17 GMT
From: Gary Coffman <ke4zv!gary>
Subject: the call to space (was Re: Clueless Szaboisms )
Newsgroups: sci.space

In article <1p261c$[e-mail]> [e-mail] (Pat) writes:
>
>Will  blats about how  japan is going to rise again on a nuclear phoenix.
>
>Please document the ROI for Nuclear Power,  once all costs have been
>allocated.

Take the cost of WWII to the Japanese, inflate it to current dollars,
and you have the de minimus value of a domestically controlled energy
source to the Japanese. Add to that the fact that the Japanese don't
approve and license their plants in adversarial proceedings. They can
go from plans to operating plants in one third the time, and one tenth
the cost it took for the last US plant to be licensed. The relative lack
of lawyers in Japan makes every business venture there less costly than
in the US. They have a fuel reprocessing plan in place, and they have a
waste disposal plan in place. They don't intend to be caught without
energy to run their industrial base, or their military, again.

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: Sun, 28 Mar 1993 16:50:57 GMT
From: Joe Cain <[e-mail]>
Subject: Venus is covered with water?
Newsgroups: sci.space,sci.astro

In article <[e-mail]> [e-mail] (James Thomas Green) writes:
>
>Noted astrophysicist Jay Leno said on the Friday 3/26 Tonight
>Show that Venus is covered with 75 feet of water!

Come on now. Anyone who has seen the JPL video based on the Magellan
data KNOWS it is covered with scrambled eggs.
Joseph Cain        [e-mail]
[e-mail]        scri::cain
[phone]        FAX [phone] or -0098

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

Date: 28 Mar 93 11:31:53 GMT
From: Del Cotter <[e-mail]>
Subject: Why is Venus so bad?
Newsgroups: sci.space

[e-mail] (Aaron Ray Clements) writes:

>[e-mail] writes:
>
>>So here is a good question, why is venus so hot? the gasses known and such and
>>the effects and such?? We need why so that we can attack the reasons why and
>>defeat them or neutralize them... Now what is the parameters for a "normal
>>planet" basically so we have something to know how to work towards??

[...]

>There's also a small problem in dealing with an atmosphere that has about
>a hundred times more pressure at the surface than at Earth.  (Do you think
>you could live in a 100atm environment?  :) )

That reminds me.  Don't forget that when you've got rid of all the CO2,
there are still 2 atms of nitrogen.  Can anyone confirm that this is
dangerously close to narcosis levels?

--
 ',' ' ',','  |                                                  |  ',' ' ',','
   ', ,','    |       Del Cotter       [e-mail]      |    ', ,','
     ','      |                                                  |      ','

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End of Space Digest Volume 16 : Issue 381
------------------------------