Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT_ZIP/spacedig/V15_1/V15NO121.ZIP/V15NO121

Internet Message Format | 1993-07-13 | 33KB

Date: Tue, 18 Aug 92 05:06:20
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #121
To: Space Digest Readers
Precedence: bulk


Space Digest                Tue, 18 Aug 92       Volume 15 : Issue 121

Today's Topics:
                             ACRV/Soyuz P
               ACRV/Soyuz P # of Passengers (2 msgs)
                 Arthur C. Clarke interview (2 msgs)
            BuckyStalks (was Re: Beanstalks in Nevada Sky)
                Early Warning of missiles and meteors
                Energiya's role in Space Station assem
               GPS (Global Positioning System) (2 msgs)
                      He3 Power Source (2 msgs)
             Mini Energiya(?) & MIR replacement (2 msgs)
                     Nevada Casino - 200 miles up
    Saturn Class Dreams (was RE:  ... and other space development)
                        SPS fouling astronomy
                          Terraforming Space
                        Tether and Space Junk

    Welcome to the Space Digest!!  Please send your messages to
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----------------------------------------------------------------------

Date: Mon, 17 Aug 92 17:17:53 BST
From: [e-mail]
Subject: ACRV/Soyuz P

> Allan you have still not addressed with numbers the propostion that
the
> Shuttle will become MORE useful as the return of large payloads
grows more
> common in the SSF era.
>

WHAT large payloads? There ARE no large payloads until we actually GO
somewhere. There is nothing in LEO to bring back. And if we do have
regular access to LEO, we should just cannibalize any hardware we
send up that stops working. Just ship new stuff up if it can't be
fixed on orbit.

Oh, true, there may be an occasional exception. But can the price of
bringing down the exception pay the full cost of keeping a standby
capability that is otherwise not required?

In any case, I think the entire discussion thread is pretty much over
moot points. The shuttle will be flying at least through the end of
the decade, regardless of what we say or what it costs. The private
measures Allan and others, including myself are suggesting will be
coming on line in the early years post-2000. The shuttle will
continue working until it is driven from the skies by economics.
Since it is the only vessel now flying, it is, by definition, the
currently most economical choice. Sad maybe, but unavoidably true.
For the moment.

The ACRV debate is a somewhat seperate issue, since there is no
capability to replace. It has a basically free shot at the emergency
return market.

If it is successful there, a good marketer can start cutting into
other facets of the shuttle market. Hell, everyone else will be doing
the same. There will be no sudden change of funding status.
Alternatives will simply kill the shuttle via the death of a thousand
cuts... over a period of perhaps 5-10 years.

The shuttle has already lived a longer time than most of the really
early cargo aircraft (ie pre-Ford Trimotor and DC-3). It will have an
honored place at NASM and will probably be sitting there before 2005.

If we are still flying 25 year old spaceships with 35 year old
technology in 2005, then one would have to assume that the United
States will have become a minor, if not trivial, player in world
affairs by that time.

For the shuttle to still be flying then would require that US private
ventures have been held back. I seriously doubt this will be the
case, so I would not fear greatly for future US world status.


Guinness is good for you            [e-mail]

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

Date: 17 Aug 92 15:37:49 GMT
From: Greg Moore <[e-mail]>
Subject: ACRV/Soyuz P # of Passengers
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Allen W. Sherzer) writes:
>In article <[e-mail]> [e-mail] (Greg Moore) writes:
>>In article <[e-mail]> [e-mail] (Allen W. Sherzer) writes:
>>>In article <h-aym4#@rpi.edu> [e-mail] (Greg Moore) writes:
>>>
>>>>    Soyuz is great, Soyuz is God, Soyuz can carry ONE passenger.  The
>>>>other two occupants must be qualified as pilots.
>>>
>>>>    The Shuttle is lousy, the shuttle is the eater of money, the shuttle
>>>>can carry 5 passengers (or more).
>>>
>>>I would like to see a source for this. The Soviets tended to prefer automated
>>>hardware and didn't let their crew do much if they could avoid it. There
>>>shouldn't be too much trouble qualifying crews.
>>>
>>
>>    Source? Look at any Soyuz flight.  If it were so easy, I'd think that
>>the CIS would be willing to fly TWo paying passengers, rather than one.
>>Also, looking at I believe the last 4 or so missions I recall 2 were done
>>with manually docking.  Finally, recall Mercury and the Capsule passengers?
>>Oh, excuse me, the ASTRONAUTS who fought to have flight control.  Trying
>>to convince NASA and/or its astronauts to sit in a capsule while it flies
>>without I think would be harder than convincing Congress of your ideas.
>>
>>>But I point out that if in fact you are correct, this is still a problem
>>>for Shuttle. Soyuz WILL be the ACRV. Congress isn't going to fund anything
>>>else.
>>>
>>    This was my fault, the subject is misleading.  As ACRV I do believe
>>that Soyuz has its merits.  As a method for exchanging crews, I have serious
>>doubts.  And you haven't made an argument yet.  Just some simple handwaving
>>about how easy it would be to qualify crews and that it would all be done
>>automatically.
>>    Heck, the shuttle can fly automatically except for landing gear
>>deployment (and that will change soon).  Why bother flying with a
>>Commander AND a pilot.  Heck, dumpt them and you have 7 or more passengers.
>>
    As has been pointed out by several sources now, I am in error on
yhe number of passengers that Soyuz can carry.  As any good debater should
do at this point, I concede the point to Allen.  Soyuz would be able to
recrew the station with the number of flights he claims.
>>
>>>   Allen
>>>--
>>>+---------------------------------------------------------------------------+
>>>| Allen W. Sherzer | "If they can put a man on the Moon, why can't they     |
>>>|  [e-mail]     |  put a man on the Moon?"                               |
>>>+----------------------252 DAYS TO FIRST FLIGHT OF DCX----------------------+
>>
>>
>>--
>><------------------------------------------------------------------------->
>>Greg d. Moore                  |  [e-mail]
>>Green Mountain Software        |  "All that is gold does not glitter."
>>Carpe Diem                     |
>
>
>--
>+---------------------------------------------------------------------------+
>| Allen W. Sherzer | "If they can put a man on the Moon, why can't they     |
>|  [e-mail]     |  put a man on the Moon?"                               |
>+----------------------251 DAYS TO FIRST FLIGHT OF DCX----------------------+


--
<------------------------------------------------------------------------->

Greg d. Moore                  |  [e-mail]
Green Mountain Software        |  "All that is gold does not glitter."
Carpe Diem                     |

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

Date: 17 Aug 92 15:45:15 GMT
From: Greg Moore <[e-mail]>
Subject: ACRV/Soyuz P # of Passengers
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Allen W. Sherzer) writes:
>In article <[e-mail]> [e-mail] (Greg Moore) writes:
>
>>>A simple return craft can be built to return these payloads in a suitable
>>>environment. Estimate the cost of this anyway you want.
>
>>    Hmm, sorry, I don't have my figures for EVA handy.
>
>Well when you can attach numbers to your complaint I will address it.
>Otherwise, it can't be considered credible.
>
    Sorry, I wasn't being facetious enough there.  My point is that
all of a sudden you've added ANOTHER cost and simply assumed your savings
are great enough that it just doesn't matter.  Since you're adding the new
requirement, I think it should be up to you add figure the cost of EVA to
remove and replace the panels instead of using the shuttle.
    Personally, I think a better bet on your side might be to
use the cost for a smaller version the LDEF that can be launched and
returned in one piece aboard a HLV or other craft.

>>>Since it achieves less reliability than commercial systems costing a fraction
>>>as much I don't think it is anything to boast about. Let's see it go on
>>>for a few years.
>
>>    How? If you kill it?  Compare the reliability of the first 50 flights
>>of the shuttle with the first 50 of any booster.  When we get more
>>shuttle flights under our belt, we use that as a better data set.
>
>Shuttle deserves to die on the basis of cost alone. Its generally
>poor relaiblity is just iceing.
>

>>>HL Delta would use Complex 37. As for Atlas, the report I mention does
>>>say that the additional six flights can be acheived.
>>>
>>    Ok, so, let's see... under YOUR plan, you need at least 2 Soyuz
>>flights to recrew that station, 4 times a year.. gives 8 flights.  Ok,
>>so where do the extra 2 come from?
>
    I don't recall your figures including the integration of Soyuz on
Atlas AND the HLV...
    In anycase, could you email my your figures.  I no longer have them
and I'd like to see them again.  Thanks.

>They go up on the HLV along with the resuply.
>
>> Given my numbers of min 3 flights
>>gives you 12 flights a year, twice the 6 you quote.
>
>Only eight Soyuz are needed. If we need 12, that simply raises the cost to
>$1.6 billion per year. Instead of saving $ billion per year we will only
>save $3.4 billion.
>
    My point about # of flights has been conceeded, your numbers are
ok here.

>>Now, where do we
>>launch the Progress and other resupply flights?
>
>the HLV of course.
>
>>What happens
>>when an Atlas is grounded (for whatever reason, I believe that you are
>>reasonable enough to admit that sometimes ANY booster can be delayed
>>somewhat) on the pad you're planning on launching your resupply mission?
>
>Since it can happen to any vehicle it can happen to Shuttle. Since we
>resuply with unmanned vehicles, gounding is a far more serious problem
>for Shuttle.
>
>I also point out that unlike Shuttle, the alternate approach has
>backups and assumes things will fail. If Shuttle fails, your dead
>in the water. If Atlas fails, you launch on Titan. If HL Delta
>fails, you use Titan V.
>
    This is actually the best part of your idea I like: Alternatives!!

>>>What isn't there is included in the estimated development costs. Like I
>>>said, the HL Delta designers know what they are doing.
>
>>    I've neer seen you quote the money to be spend on intergration
>>facilities, etc.
>
>Nevertheless they ARE included.
>
>>>Look, McDonnell Douglas offered the government 20 HLV flights at a fixed
>
>>>price.
>
>>    Oh Allen? What do we need 20 flights for?
>
>That represents ten years of station resuply.
>
>    Allen
>
>--
>+---------------------------------------------------------------------------+
>| Allen W. Sherzer | "If they can put a man on the Moon, why can't they     |
>|  [e-mail]     |  put a man on the Moon?"                               |
>+----------------------251 DAYS TO FIRST FLIGHT OF DCX----------------------+


--
<------------------------------------------------------------------------->
Greg d. Moore                  |  [e-mail]
Green Mountain Software        |  "All that is gold does not glitter."
Carpe Diem                     |

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

Date: Mon, 17 Aug 92 17:15:46 GMT
From: Dave Jones <[e-mail]>
Subject: Arthur C. Clarke interview
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Tom O'Reilly) writes:
>Apparently Arthur C. Clarke was interviewed on NPR last week. I didn't
>catch it - anybody have a synopsis?
>

I caught a fragment.  It seems to have been inspired by the tethered
satellite experiment, giving Clarke a chance to push the Orbital Tower
idea.  He reiterated his contention that it takes only $100 worth of
energy to "get up there", by which I assume he means GEO, which is the
lowest orbit per se that you can get to via beanstalk.  I find that a
little hard to believe.  I could believe 200km, but then you wouldn't
be in orbit.  If you had a counterbalance system that sent mass down
at the same time as other masses went up, you might make it to GEO for $100.

--
||)) Dump the Whatizit!  Ren and Stimpy for Olympic mascots in '96 ! )))))))|
||)) "What is it, man?!?" ))))))))))))))))))))))))))))))))))))))))))))))))))|
||))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))|
||Dave Jones ([e-mail]) | Eastman Kodak Co. Rochester, NY   |

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

Date: 17 Aug 92 19:01:20 GMT
From: "Thomas H. Kunich" <[e-mail]>
Subject: Arthur C. Clarke interview
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Dave Jones) writes:
>I could believe 200km, but then you wouldn't
>be in orbit.  If you had a counterbalance system that sent mass down
>at the same time as other masses went up, you might make it to GEO for $100.
>
I have a hard time dealing with the dynamics of a beanstalk. Since you
are moving mass up and down this thing, how do you retain the center of
gravity at the geosyncronous point? As the asronauts have found, manuevering
is very difficult and fuel intensive because of this problem.

As I understand it (though I worked the figures out a long time ago) the
small changes in center of gravity that are affected by these mass changes
turn out to be rather critical.

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

Date: 17 Aug 92 19:32:27 GMT
From: Quagga <trystro!quagga>
Subject: BuckyStalks (was Re: Beanstalks in Nevada Sky)
Newsgroups: sci.space

Geesh I hope I do this right...

For a reference on Buckytubes, see Science News Vol 142, 18 July 1992,
page 36. This is a relatively recent article. Buckyballs/tubes/Buckminster-
Fullerene/C-60 has been a hot topic... you might also peek in sci.materials
occasionally...

Quagga @ trystro.uucp
(But you can call me Cheryl)

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

Date: Mon, 17 Aug 92 17:11:22 BST
From: [e-mail]
Subject: Early Warning of missiles and meteors

> they could detect it; if their systems were looking.  the military
> is rather sensitive about how sensitive their equipment is.  they
>


I would tend to agree. However, from your description, I could
suggest a scenario by which it could slip through.

    a) As you say, on a  hyperbolic orbit it would not be
       detectable until it got fairly close .

    b) The entry point may have been over the continental US and
       heading OUT into the ocean, thus it would not have been in

       the coastal watch until very late and may have
       been there for such a short time as to be missed entirely.

Or, as you said, they seen it and the ain't talkin'....

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

Date: 17 Aug 92 18:50:39 GMT
From: Doug Mohney <[e-mail]>
Subject: Energiya's role in Space Station assem
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Matthew DeLuca) writes:
>In article <[e-mail]> [e-mail] (Allen W. Sherzer) writes:
>>In article <[e-mail]> [e-mail] (Gary Coffman) writes:
>
>>>Name *one* major military procurement that
>>>proceeded on a fixed price basis with *no* adjustments.
>
>>The ATF prototype
>>LACE
>>RME
>>DC-X
>
>We've procured DC-X's already?  How did the first launch go?
>
>(For the sarcasm impaired: these aren't procurements.)

He also left out the difficulties in seeing DC-X to fruition (i.e.; one attack
on funding already), but don't let sweating the details stop him...


                 Support U.N. military force against Serbia

  -- >                  [e-mail]                        < --

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

Date: 17 Aug 92 17:09:24 GMT
From: Jeff Bytof <[e-mail]>
Subject: GPS (Global Positioning System)
Newsgroups: sci.space

I have just read the famous 76-page brochure on GPS put out by Trimble
Navigation.  It hardly qualifies as a manual or technical documentation.
When I call Trimble Navigation for information, they give me the phone
number of a guy that won't be back for two weeks.  According to the
brochure, US taxpayers are "investing over $12 billion" on the system.
I would think there would be at least an address I could write to for
a good bibliography on the system without having to go through some
company that makes it money keeping public information away from the public.

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

Date: 17 Aug 92 20:24:46 GMT
From: Kenneth Gordon <[e-mail]>
Subject: GPS (Global Positioning System)
Newsgroups: sci.space

In article <[e-mail]> Jeff Bytof, [e-mail]
writes:
>I have just read the famous 76-page brochure on GPS put out by Trimble
>Navigation.  It hardly qualifies as a manual or technical documentation.
>When I call Trimble Navigation for information, they give me the phone
>number of a guy that won't be back for two weeks.  According to the
>brochure, US taxpayers are "investing over $12 billion" on the system.
>I would think there would be at least an address I could write to for
>a good bibliography on the system without having to go through some
>company that makes it money keeping public information away from the
public.

A good place to start looking might be the USAF Space & Missile Systems
Center
Office of Public Affairs.  The USAF SMC is the organization which
procures and launches GPS.  Their telephone number is [phone].  If
they cannot help you, hopefully they would be able to put you in touch
with someone who can.

- Ken Gordon
  [e-mail]

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

Date: 17 Aug 92 15:56:55 GMT
From: Don Roberts <[e-mail]>
Subject: He3 Power Source
Newsgroups: sci.space

[e-mail] (Scott Hannahs) writes:
>
>Any reason the moon should be richer in 3He than the earth? The natural
>abundance of 3He is about 7ppm in regular 4He which is from trapped
>alpha decay in natural gas wells. [...]
>The major (only) commercial source of 3He (~$90 >US / liter STP federal
>research grant rates) is from nuclear weapons manufacture. [...]
>Now that the arms race is over all the low temp physicists should start
>worrying about the availability of 3He. For awhile as warheads are
>deactivated things will be ok, but eventually....  No more research below
>1K.  We do recycle the stuff but nothing is 100% effecient.
>
>Scott Hannahs, F. Bitter National Magnet Lab, [e-mail]

The only reason I've heard for high abundance of He3 on the moon is the
solar wind. With neither a magnetic field nor an atmosphere, the moon
just scoops the stuff up, whereas the earth pushes it out of the way.

As for He3 from tritium decay, the condensed matter crowed better hurry
up and finish their low temperature research. There might be a fair bit
of tritium in the retired stockpile now, but there isn't *any* new
tritium being produced. In the (unlikely) event that we get D-T fusion
working in the next 12.32 years (to pick a number out of thin air :),
you won't even have much of *that* to play with.

--
 Dr. Donald W. Roberts
   University of California                                      Physicist
   Lawrence Livermore National Laboratory         Recreational Bodybuilder
   [e-mail]                                       (better poo? :)

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

Date: 17 Aug 92 18:08:22 GMT
From: Charles Frank Radley <[e-mail]>
Subject: He3 Power Source
Newsgroups: sci.space

-
>From: sth0:05:28ipknot.mit.edu (Scott Hannahs)
> Organization: Massachvsetts Institvte of Technology
> Date: 14 Aug 92 23:50:11 GMT
> Subject: Re: He3 Power Source
>
>
> Any reason the moon should be richer in 3He than the earth? The natural
> abundance of 3He is about 7ppm in regular 4He which is from trapped
> alpha decay in natural gas wells.
-
I do not know how the abundance compares.   He-3 on the Moon comes from
bombardment by solar wind particles, which has been continuing for a
few billion years.  Unlike Earth, the Moon has no atmosphere, no magentic
field, and no Van Allen belts, so is completely exposed to the raw solar
flux.
By comparison, none of the solar particle flux reaches Earth's surface.

>I think the energy cost of gettting
> to the moon, mining the 3He and bringing it back would be more than you
> can get out of the 3He.  The major (only) commercial source of 3He ($90
-
Quick lesson in lunar economics :-
Transportation from the Moon would be by solar powered electromagnetic mass
driver. Operating costs essentially nil (except maintenance).
A modest one time capital cost will be incurred to launch and install the
small mass driver on Moon.  After that, you can transport infinite
quantities of lunar material for virtaully zero cost.
   Extracting He-3 from lunar soil is cheap and simple - heat it up a
little, using solar mirrors.   The cost of storing He-3 in its refined
state is more expensive than handling lunar soil, so it might be cheaper to
launch lunar soil to Earth, rather than the He-3, despite the fact that the
mass of the soil is much higher, the cost of transporting it is very low.
-
> US / liter STP federal research grant rates) is from nuclear weapons
> manufacture.  If you have some tritium around all you have to do is sit
> on your thumbs and bingo 3He.  Now that the arms race is over all the
> low temp physicists should start worrying about the availability of 3He.
> For awhile as warheads are deactivated things will be ok, but
> eventually....  No more research below 1K.  We do recycle the stuff but
-
And He-3 is elusive stuff.
It should be quite cheap to supply lunar He-3 to Earth for whatever
purpose.
Is there an easy way to store He other than cryogenci or gaseous ?  EG can
it be soaked into something, say, Palladium or Lithium (like Hydrogen) ?
It is already soaked into lunar soil, but at rather low concentrations.

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

Date: 17 Aug 92 15:55:43 GMT
From: Charles Frank Radley <[e-mail]>
Subject: Mini Energiya(?) & MIR replacement
Newsgroups: sci.space

How does Energia-M compare with Proton in cost and
lifting capability ?

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

Date: Sun, 16 Aug 1992 19:15:28 GMT
From: Dennis Newkirk <[e-mail]>
Subject: Mini Energiya(?) & MIR replacement
Newsgroups: sci.space

In article <[e-mail]>
[e-mail] (christian stelter) writes:
>What you have seen was called Energia-M

The Energia-M test article was put on the Energia launch pads for fit checks
several months ago.  Photos of the booster appeared shortly afterward in
magazines and books.

>The core - module of Mir had some breakdowns....
>cheaper to replace this core with a new improved
>version

A clarification:

Originally, plans called for the new core to be launched by Buran and
a complex redocking to take place reattaching all or some of the old
Mir modules to the new Mir-2 core.

Now, the concensous in the Russian press reporting of Mir-2 seems to
indicate that the Mir-1 core will not only be replaced, but an all new
complex will be assembled with new modules as well.

This will be necessary since by the time Mir-2 will be ready,
Kristall, Kvant and Kvant 2 will be nearing their design limits. And,
depending on the availability and need for the as yet unlaunched Mir-1
modules, this may give the Russians the option to increase the
inclination of Mir-2 to 65 degrees to allow for Plesetsk resupply
missions.

Dennis Newkirk
Motorola Inc, Land Mobile Products Sector
Schaumburg, IL

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

Date: 17 Aug 92 17:28:13 GMT
From: "Blair P. Houghton" <[e-mail]>
Subject: Nevada Casino - 200 miles up
Newsgroups: sci.physics,sci.space,rec.gambling

In article <[e-mail]> [e-mail] (Vincent Frisina) writes:
>In article <[e-mail]> [e-mail] writes:
>> Situation:  I need to place a casino 200 miles over Nevada with a
>> tether below it for elevators.  I have access to 2026 AD technology.

>   Could you be more exact as to what 2026 AD technology is?

The sort of stuff we get twelve years after Louise has
earned her PhD.  Should be bitchin'.

>> Questions:  What amount of power would the casino need to stay over
>> one spot in Nevada?

I'll leave that to the rocketeers in sci.space.  They'll
probably suggest a better orbit (although I think
geosynchronous is a bit out of the way for junkets...).

>>What would be a good source of this power?

Something expendable.  There are no electric cars
in space.  Even ionic systems require a propellant.

>>What should the tether be composed of?

Bob Stupak's hair.  We in rec.gambling are all certain
it's some sort of space-age polymer.

>>What will be the weight capacity of the tether?

If you get the propulsion right you'll only need to
support the weight of the tether itself.

                --Blair
                  "Come onnnnnn, SEVEN!
                   Daddy needs a new
                   pair of heavy boots!"

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

Date: Mon, 17 Aug 92 18:02:59 BST
From: [e-mail]
Subject: Saturn Class Dreams (was RE:  ... and other space development)

> It is easier to build the engine tooling. And for the skeptical out
there. The
> engines for the Delta, Atlas and Titan lines had been discontinued
due to the
> theoretical reliance on the Shuttle for all launches.  The
production lines for
> those were restarted and the Rockewll folks say that the F1A
restart would be
> the same.  Yes Virgina some of the suppliers for F1 and F1A parts
are gone but
> the Rockwell people said the same thing about the other engines and
they were
> able to get other suppliers for componets of the engines.
>


I would basically agree with you, but there IS one serious difference
between the F1A and the Atlas. It is the human skill base, NOT the
tooling that is most critical. I expect many of the top F1A people
are long gone, some where we can't even ask (unless you can get
funding for some channelers :-) The key Atlas people were probably
just transferred to other divisions/projects and thus easily brought
back.

So I expect the F1A restart would be much harder than the Atlas. BUT,
that said... I still don't think it is as big a deal as some try to
make it out. After all, this is not a high tech engine any more. It
is just an old fashioned BIG engine. Should be no problem t'all.

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

Date: 17 Aug 92 19:57:09 GMT
From: Curtis Roelle <roelle@uars_mag.jhuapl.edu>
Subject: SPS fouling astronomy
Newsgroups: sci.space

[e-mail] (Frederick A. Ringwald) writes:

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

>> > Also, the objection that
>> > "there'd be nowhere on Earth you could get away from the handiwork of
>> > humans - no remaining true wilderness" isn't really true: try Alaska
>>
>> I give up.  The lattitude is only 60 to 70 degrees or so, and there
>> are plenty of flat places where the horizon is visible. And the
>> aurora is seldom bright enough to obliterate the bright planets.
>> Maybe you were there during a _really_ bright display. :-)

>Trees could block objects near the horizon, but come to think of it,
>you'd have to be above latitude 82 degrees, which is more northerly
>even than Point Barrow, to get completely away from the
>Con-Ed-stellation. GEO is about 6.6 Earth radii away, and
>arctan(6.6) = 81.4 degrees (My thanks to Mike McCall from Rutgers
>for pointing this out.); atmospheric refraction will give
>another 34'.

Are there really persons out there who believe a fair assessment of
the physical universe can be made by restricting our view to the
celestial cones around Earth's polar regions?

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

Date: Mon, 17 Aug 92 20:27:19 GMT
From: "Thomas H. Kunich" <[e-mail]>
Subject: Terraforming Space
Newsgroups: sci.space

There have been suggestions of terraforming Mars, perhaps
even Venus. There may even be other planets or satellites
in the solar system that lend themselves to being improved
upon by man.

Well, I have a suggestion.

We can talk of sending manned flights to Mars, but we do
not have the technology yet, nor the budget for such a
prolonged and possibly ineffective space flight. Maybe we
haven't learned from recent attempts to mass produce
science, but miracle breakthoughs simply don't happen on
schedule if ever. So talk about terraforming with unknown
technologies is premature to say the least.

Yet we do have the capability of terraforming Mars or the
very least modifying Mars to support life of some sort. The
same could probably be said of Venus and other places.

If the Gaia principle really exists, and I find the
principle attractive, then we can let life do it's own work
on these planets.

It is a simple, possibly even elementary, matter to find
various bacteria, algae, fungi, lichen etc. that can exist
in the harsh environment of Mars. Or, for that matter, the
upper reaches of the Venusian atmosphere. These life-forms
are small, light and quite capable of being transported in
rather massive quantities to these planets by presently
possessed technology. Should there not be appropriate life
forms, our present knowledge of biotechnology should lead
us to be able to develop some in fairly short order.

I suggest that we send a space vessel bearing our life
substitutes to Mars and Venus. The cost is relatively
miniscule. Thereon we can sprinkle the makings of man
himself.

Oh, maybe the results won't look like our ideas of life. If
Gaia lives on Venus I am sure that she is a Venusian Gaia.
We would find her, perhaps, a little hot blooded for our
tastes. The Martian Gaia might be more to our liking but
then again who is to say? So too for the Titan Gaia.

Would the Gaia principle work? I, for one, think that it
would. In any case the results would be a satisfying and
informative experiment that would cost pennies along the
lines of space travel these days.

Of course it would be unethical to interfere with any life
there may be already there. So considerable exploration
would be necessary to give a moral basis for such a
project. But consider this:  Should man never be able to
budge from this planet in earnest we will have had our
moment of godhood and brought life to pass. And perhaps,
after all, that is the true meaning of life.

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

Date: 17 Aug 92 16:35:44 GMT
From: Scott Stanford <[e-mail]>
Subject: Tether and Space Junk
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Robert Bunge) writes:
>In article <[e-mail]> [e-mail] (clifford bettis) writes:
>>
>>I have been waiting to see this issue discussed: in the event of
>>serious difficult with the tethered satellite experiment, I understand
>>that one option was to cut the tether. Wouldn't a 20 km cable in orbit
>>be the environmental equivalent of a drift net for space craft and
>>pose an unacceptable hazard?
>>Cliff Bettis
>
>A follow up to the above question is what happens when a 12 to 20 or
>so mile-long tether starts to re-enter the Earth's atmosphere?  Aren't
>the Russians planning on flying a tether experiment and cutting it at
>the end of the experiment?  Would a long tether burn up?
>
>Bob Bunge


>[e-mail]

















I'm using an editor on a weird system, so sorry if the following is
illegible or scrawled all over the previous article:


I don't think the length of the tether should matter in regards to it
burning up in the atmosphere - it is mainly the cross-section that
should matter (or perhaps more appropriately the volume to surface
area ratio and the material of the tether).  As long as the heat of
reentry eats through the same amount of "cubic inches per unit time"
on the surface of the tether, it should be able to eat up a tether of
any length in the same amount of time.  Come to think of it, if it's
copper or some similar mat'l, it should look pretty sweet if it's
anything like the experiments you do in physics and materials classes
(quite a glow).

Does this sound right?

--
Scott Stanford                 (;@~)  (`@<)
                             |\____________/|
[e-mail] |  \/  \/  \/  |
                              \___/\__/\___/  The BIG FACE is your friend.

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End of Space Digest Volume 15 : Issue 121
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