Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v15_1/v15no106.txt

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Date: Fri, 14 Aug 92 05:00:07
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #106
To: Space Digest Readers
Precedence: bulk


Space Digest                Fri, 14 Aug 92       Volume 15 : Issue 106

Today's Topics:
              Beanstalks in Nevada Sky (was Re: Tethers)
                Energiya's role in Space Station assem
                 Energya and Freedom and Soyuz ACRV
                          handheld astronomy
NASA statement on Earth Data System proposals [NTE 92-71] (Forwarded)
                          Parsecs? (3 msgs)
                        Seeding Mars with life
             SPS feasibility (WAS: SPS fouling astronomy)
                               Tethers
                      Upcoming Delta launches...
           Weak interactions, biology and the SSC (2 msgs)
              Why is this on SpaceDigest (or sci.space)

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

Date: 12 Aug 92 19:33:45 GMT
From: Bruce Watson <[e-mail]>
Subject: Beanstalks in Nevada Sky (was Re: Tethers)
Newsgroups: sci.space

In article <[e-mail]+ [e-mail] (Bill Higgins-- Beam Jockey) writes:
+In article <[e-mail]-, [e-mail] writes:
+- Would it be possible to put something in near orbit over Nevada and
+- attach tethers to it so that people could reach the object via
+- elevators?  I know it wouldn't be easy, but is there a way to pull
+- this off?
+
+Hmm. Interesting question.  To first order:  No, it's impossible, for two
+reasons.
+
+When you say "orbit," you usually mean "Keplerian orbit," a free body
+that stays on its path without applying any thrust.  Nothing in a
+Keplerian orbit can hover over Nevada, since the plane of its orbit
+*must* pass through the center of the Earth.
+
+It *is* possible for an object in orbit to hover over a spot on the
+Equator, if it takes exactly 24 hours to make one revolution AND its
                              ^^^^^^^^
                              23 hours and 56 minutes
--
Bruce Watson (wats@scicom)  Tumbra, Zorkovick; Sparkula zoom krackadomando.

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

Date: 13 Aug 92 05:27:13 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Energiya's role in Space Station assem
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:
>In <[e-mail]> Matthew DeLuca writes:
>>Allen, why won't you understand that there is more involved than simple
>>finance here?  You can 'save' $3 billion, but you better be happy spending
>>that $3 billion on social welfare programs, because it sure as hell won't be
>>spent in space.
> Without wishing to buy into US politics, I will merely point out
>that you are being pretty free with other people's money here. There is
>no requirement that any savings be spent elsewhere, as I understand that
>the US has a significant budget deficit which could do with a bit of
>help.

Yes, but the "savings" Allen quotes is 0.1% of the debt and there is
absolutely no guarrantee that Congress would apply any such "saving"
to reducing the debt. Indeed, Congress has shown a strong tendency
to spend every dime it can extort and borrow from the US taxpayer.
The space budget is literally less than nickels and dimes in the
US budget dollar, which is probably as it should be for such a long
term investment.

What is dangerous is the attitude that it's all right to kill Shuttle
or Fred to save such sums when it's an almost certainty that they
would *not* be reprogrammed to other space projects, but instead
would be redirected to welfare programs. To anyone willing to look,
social welfare programs have been counterproductive in nearly every case.

Gary

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

Date: 12 Aug 92 06:55 PDT
From: Mark Goodman <[e-mail]>
Subject: Energya and Freedom and Soyuz ACRV
Newsgroups: sci.space

Quoting Allen Sherzer:

>Come now Mr. DeLuca, your grasping as straws. When fabrication begins
>it won't take long to build another. As to killing the project, not
>likely give the huge and lasing political support it has received.

I am not aware of any huge and lasting support.  The House votes have
been about 230-180, far from 2-1, and then only because the aerospace
industry has already received such a big hit from DoD cuts.  There is
tremendous opposition to the space station, which is based on the
essential question: what good is it?  What benefits does it offer the
average taxpayer in return for its $1000/taxpayer cost (order of
magnitude)?  That's a question I certainly can't answer.

>First of all, even if I agreed with that, so what? Just because somebody
>else will waste money doesn't give us any right to waste. As a taxpayer,
>I am rather pissed that NASA wastes so much; I'm also pissed about all the
>other waste. All this attitude does is help keep space expensive and prevent
>private efforts from taking off.

This is, of course, the reason reason Allen is basically correct, in
spite of his often "imaginative" arguments.  As a taxpayer, I cannot
support the Space Station unless NASA does everything it can to reduce
its costs.  That includes using former Soviet (let's not say CIS --
the Commonwealth of Independent States will soon be a memory) technology
where feasible.  Frankly, I haven't seen any showstoppers regarding
Energiya or Soyuz.

>Since these will open the space frontier and produce far more tax income,
>it seems a good idea.

Allen, if you are refering to the Space Station, a Moon Base, or planetary
exploration, my reaction is: Come on, give me a break.  If you are
refering to investments in near-term space technology (improved ELVs,
perhaps SSTO, improved automation and remote control, lightsats, etc.)
and R&D on more distant prospects (NASP, etc.), I agree.  Which is it?

+-----------------------------+-----------------------------+
|       Mark W. Goodman       | What a terrible thing it is |
| [e-mail] -- econet | to lose your mind.          |
| [e-mail]  |                             |
+-----------------------------+-----------------------------+

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

Date: 13 Aug 92 12:35:38 GMT
From: [e-mail]
Subject: handheld astronomy
Newsgroups: sci.space

GREETINGS all Aliens and Earth's Beings !!

Have you run into the Phobos or other Heavenly Objects lately ?
You haven't !
Ok, It's good because I was downloaded my program in to the News Group
COMP.SOURCES.HP48. Its name is TYKO and v=3.0. And by the help of this
program you can easily locate those objects so there are no difficulties
to take your bearings in time or space.

Some features;

   8.5 planets, Moon, Sun, 21 stars and available coordinates;
   Rising  times      Visual magnitude            Ecliptical (Geo or Helio)
   Setting  #         Apparent #                  Equatorial
   Color index   Geocenric distance               Horizon
   Heliocenric distance  Semidiameter  Diameter Nutation in everywhere
   Obliquity of the Ecliptic  Equation of Equinox Sidereal times Universal
   time Ephemeris transit times Perihelion dates Mean anomaly Mean
   longitude Elongation Phase Calendar Easter Sundayes and ...  so on.

   And the input can be both the Calendar date -- either Gregorian date or
   Julian date -- and Julian day. For instance; you can put the date
   January 2. 3456789 and time 12.36 in the form 1264287318.02 (TZ=0,
   Calendar=Gregorian) and you will get excatly the same results
   ( the accuracy can be a little questionable ).

  And all This from your Handheld, you do not need to drag those
  exhausting, not VERY Personal, Computers with yours when you are
  e.g. on the lake in rowboat or having lunch with other aliens from
  Pleiades.

I have also some HP48sx pictures, are called GROB-picts,
so if you want to see them ...  mail please.
I compined and converted them into three GIF-picts.

PS. The DOC file has been written in VSL so be patient -- pleeez !
The latest version is 3.01, if you got 3.0 please replace it.
regards,
kati

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

Date: 13 Aug 92 14:59:57 GMT
From: Greg Moore <[e-mail]>
Subject: NASA statement on Earth Data System proposals [NTE 92-71] (Forwarded)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Peter E. Yee) writes:
>
>NASA STATEMENT ON EARTH DATA SYSTEM PROPOSALS
>
>    NASA today issued the following statement regarding
>the Earth Observing System Data and Information System
>Core System acquisition:
>
>NASA CALLS FOR REVISED PROPOSALS FOR THE EARTH OBSERVING
>DATA AND INFORMATION SYSTEM CORE SYSTEM ACQUISITION
>
>
    [stuff deleted for brevity's sake and Mike's sake]

>    As prescribed by NASA source selection regulations,
>the evaluation of proposals included a "most probable
>cost" analysis of each proposal as reflected in the
>"best and final offers" submitted by the offerers.
>Despite NASA's repeated attempts during the solicitation
>and evaluation processes to encourage the submission of
>realistic cost estimates, the government's analysis
>clearly indicates that the offerers significantly
>underestimated the cost of the respective technical
>approaches.  Accordingly, NASA is unwilling to select an
>offerer for further negotiations leading to award of a
>contract.
>
    Now, am I reading this right?  Every submitter said they
could do it for around $X and NASA and the government is saying,
oh no... you can't do it for $X, it's a lot more than that!  Until
you say it will cost more we won't award the bid.

    It seems to me that if EVERY contractor said they could do
it cheaper than the government says it will cost, maybe the
contractors know something?  After all, I'm sur they are in there
to make money, not lose it.

    I can understand if one company was way low.  In that case,
sure you probably don't want to go with the lowest bidder.  But if
EVERY company is way low? Come on.

So, please, if I'm misunderstanding this, please let me know why
the goverment wants to spend more money?
(And no, the answer is not that every company is using Soyuz. :-)

>    Extensive analysis of the proposed technical
>approaches shows that the proposals reflect sound
>technical approaches and exhibit a reasonable
>understanding of the program to be accomplished.
>Whatever the reason for the underestimation of cost, the
>end result is unrealistic cost proposals that do not
>provide a satisfactory basis
>for constructive negotiations.
>
>    NASA has elected, therefore, to offer an additional
>opportunity for offerers in the competitive range to
>adjust the proposed costs to a more realistic level.  In
>instructions issued by the Goddard Space Flight Center
>on Aug.10, 1992, as an amendment to the solicitation,
>NASA has directed the offerers to submit revised cost
>proposals. Changes to the previously submitted technical
>and business management proposals will not be
>considered.
>
>    In addition, Goddard Space Flight Center has
>provided the offerers with the provision that will be
>used to evaluate the contractor's cost performance
>during the contract period.  This provision assesses
>significant reductions to the award fee if the
>contractor fails to manage and control the program in
>accordance with the costs proposed.
>
>    Revised cost proposals that realistically reflect
>the requirements of the solicitation and the proposed
>technical approach are to be submitted by 1 p.m. EDT on
>Aug. 31, 1992.  By the end of September 1992, NASA
>intends to select an offerer for negotiations leading to
>contract award.


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

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

Date: 13 Aug 92 09:00:57 GMT
From: Keith Allan Schneider <[e-mail]>
Subject: Parsecs?
Newsgroups: sci.space,sci.physics

[e-mail] (Ron Echeverri) writes:

>In article <[e-mail]> [e-mail] (Keith Allan Schneider) writes:
>>Hmmm...  at the distance of one parsec, one astronomical unit subtends an
>>angle of one arc second.

>Coincidence.  Remember, one AU is the distance from the Earth to the Sun...

No, THAT, my friend, is the DEFINITION of a parsec...

>5150
>look ma, i can nitpick too! :)

huh?  or not

keith

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

Date: 13 Aug 92 14:36:08 GMT
From: Mikko Tsokkinen <[e-mail]>
Subject: Parsecs?
Newsgroups: sci.space,sci.physics

In article <[e-mail]> [e-mail] (Craig "Powderkeg" DeForest) writes:

> This talk of parsecs and so forth reminds me of my favorite volumetric unit:
> the barn megaparsec.

> A barn is a unit of atomic cross-section, 10^-20 cm^2.  A barn megaparsec is
> about 1.6 teaspoons!

> --
> Craig DeForest:  [e-mail]  *or*  [e-mail]

And from jargon file:

attoparsec: n. `atto-' is the standard SI prefix for
   multiplication by 10^{-18}.  A parsec (parallax-second) is
   3.26 light-years; an attoparsec is thus 3.26 * 10^{-18} light
   years, or about 3.1 cm (thus, 1 attoparsec/{microfortnight}
   equals about 1 inch/sec).  This unit is reported to be in use
   (though probably not very seriously) among hackers in the U.K.  See
   {micro-}.

 Mit
xxxxx
--
Save bandwidth and nerves! Use small signature!
--

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

Date: Thu, 13 Aug 1992 14:41:35 GMT
From: Richard Martin <[e-mail]>
Subject: Parsecs?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Jim Carr) writes:
>In article <[e-mail]> [e-mail] (Craig "Powderkeg" DeForest) writes:
>>
>>This talk of parsecs and so forth reminds me of my favorite volumetric unit:
>>the barn megaparsec.
>>
>>A barn is a unit of atomic cross-section, 10^-20 cm^2.  A barn megaparsec is
>>about 1.6 teaspoons!
>
>Cute, but I have always preferred the Hubble-barn.  Granted, the exact
>value of the Hubble constant is not exactly agreed upon, but I like
>the fact that if you multiply the size of the universe (one uses the
>Hubble length, obviously) by 1 barn you get something like 16 liters.
>My notes are scribbled in the back of "Gravitation", which is at work,
>but memory says that a Hubble-barn is the volume of a straw that has an
>opening the size of the nucleus of silver and reaches to the edge of
>the universe.  BTW, a barn is 10^{-24} cm^2 -- 1 fm^2 = 10 mb.

I don't know about that definition, but I'd like to see the question
from this year's SIN (Sir Isaac Newton) Contest put up here.  Anybody
from Waterloo in a mood to put it up?  We were asked to figure out what
the conversion from carats/(barn*yard) to metric was...it was sort of
cute, and the first I'd ever heard of the barn.
Richard.  =) Thanks for the interest, and the explanations!

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

Date: Thu, 13 Aug 92 12:16:05 BST
From: [e-mail]
Subject: Seeding Mars with life

Life started in a reducing, not an oxidizing atmosphere. If Mars has
primitive life forms, then I would expect it to be anaerobic types
unless evolution proceeded fast enough to make it to the
photosynthesis/aerobic phase. Even if it did, it's currently reduced
state would be a strong argument that such died out. But that does
not necessarily mean the primitive ones did as well.

The point about energy source is a good one. I would have to see I
simply don't know.

But it is telling that live bacteria have been retrieved from MILES
under the Earth.

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

Date: 13 Aug 92 07:50:37 GMT
From: Gary Coffman <ke4zv!gary>
Subject: SPS feasibility (WAS: SPS fouling astronomy)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:
>In article <[e-mail]>, [e-mail] (Frederick A. Ringwald) writes...
>>
>>Again, WHAT reasons? Electric cars do not require SPS for their
>>development.
>
>No but converting a transportation infrastructure that runs on billions of
>gallons on Hydrocarbons per year to one of running on Terawatts of electricity
>will require a vast increase in electrical production. Where else are you
>going to get the energy in a non, polluting manner. The thermal pollution of
>SPS is miniscule compared to tradtional technologies.  Also the laser is tuned
>to a frequency that will not be absorbed by the atmosphere.

Let's look at this a bit closer with some ROM estimates. If we have a 1 TW
laser beam from the Moon impinging Earth, we add an additional TW to the
Earth's heat balance. Normal heat input from the Sun for the Earth is
about 140 TW so the additional 1 TW is less than a 1% change. But due to
efficiency factors discussed below, actual net heat load would be 3 TW.
By contrast, for Earth based solar collection, there is no net increase
in heat flux. The energy is striking the planet anyway whether we use it
or not. All of the energy eventually radiates back to space after being
used since any electrical equipment's energy usage ultimately degrades
back to heat. Note also that 1 TW of nuclear generated electricity also
increases the heat load on the Earth by 3 TW, just like the laser system.
Meanwhile, geothermal generation of 1 TW of electricity increases the heat
load of the planet not at all, the heat's already here. So direct Earth
based solar capture or geothermal are "free" energy while nuclear and Lunar
Laser are sources of additional planetary heat. Plus, nuclear is cheaper
than lunar, so if we're going to increase the heat load on the planet, we
might as well do it with nuke plants.

Now what's happening on the Moon? Gas lasers are very inefficient devices.
I don't have CO2 numbers at hand, but He-Ne efficiencies are around 0.1%.
Giving an advanced CO2 laser a 10% efficiency is likely generous. Now to
convert the IR back to electricity the Earth based receiver is either going
to be photovoltaic cells, or some thermal system. In either case, efficiency
is under 30%. That means that 34 TW of electricity has to be input to the laser
on the Moon to deliver 1 TW at the power receiver busbar on Earth. Now the
same efficiency factor is at work on the Moon as on Earth for converting
light energy to electricity, so now we're talking around 100 TW of captured
solar energy on the Moon for 1 TW delivered to the busbar on Earth. Note that
I am totally neglecting transmission losses through the atmosphere of the
laser beam. Now solar energy striking the top of the Earth's atmosphere, or
the surface of the Moon, is 1 kW/m^2. So our 1 TW delivered to the busbar on
Earth requires a solar collector area of 1E14 square meters on the Moon. That
requires a square 10,000 km on a side, or about 6,000 miles on a side. Sorry
gentlemen, the Moon isn't that big. Now if we discard the laser, the Moonbase
with it's 6000 mile on a side collector, and simply use the same collector
field we were going to use for the laser on Earth, we still gather in 1E10
watts, or 10 GW, and we haven't spent an improbable fortune on the Moon.
Note that if we assume 100% laser efficiency, we are still talking about
a collector field on the Moon of 1E13 square meters, or a square 3200 km
on a side. Still too big.

A Lunar collector array would be in darkness 2 weeks out of 4, so storage
for two weeks would be required on Earth. For an Earth based array, only
8 to 12 hours of storage would be required for a single site. Since all
of Earth uses, or wishes to use, power, multiple sites around the globe
make sense to reduce transmission losses. Therefore, at least half of
Earth's capture arrays would be in daylight at any given moment. That's
at least 7 times better than the Loony Laser.

>>> All development of solar tech in the U.S. is carried out by SDIO and they
>>> just got their throat cut by congress critters pushing bread and circuses
>>> at the expense of the future.
>>
>>Did you say all? This is news to me.
>>
>Too bad you don't read the news.  There is some work being done by Sharp of
>Japan on BSFR enhanced silicon cells. They are the only ones outside of SDIO
>doing any meaningful work.  Here is a list of the developments and the sponsors
>
>AlGaAs/CuInSe2 thin film tandem cells [Boeing Defense & Space & Kopin Corp]
>GaAs/Ge tandem cells [TRW]
>Amorphus (sp) silicon cells [sponsored by Larry Labs]
>
>There is no other development except a little by TI that I read about recently.
>The first two above are high efficiency cells (over 22% with Boeing up to 37%
>for the concentrators and 26% on Planar) For more information here I suggest
>you read my and my partner's paper on the SEDSAT 1 advanced power system
>technology demonstration satellite from last year's Small Sat Conference.

I'm sure SERI, EPRI, and Arco, just to name three *US* solar research
activities, will be amazed to learn that only Star Wars is doing research
on solar energy. SoCal Edison seems to think solar generated electricity
is profitable *now* on Earth since they're building a plant. Luz was
*almost* profitable at today's peaking prices. Most of the necessary
research has already been done, everybody is just sitting back waiting
for the price of fossil fuels to rise a bit before making large commitments
to *proven* solar technologies. Photovoltaic cells are not the *best*
way to use solar energy, and likely never will be for large scale power.
But solar *thermal* is workable *today* in certain cases.

>>> No we say that we must finally open up the last frontier to development. No
>>> single technology or service from space will justify the expense BUT, taken
>>> together, the development of the resources of the solar system, whether it
>>> be solar energy from space, materials from the Moon, asteroids, and other
>>> planets will raise the planetary standard of living to a height that will
>>> make today look like the abode of dirt dwellers.

So we lose money on every sale, but we make it up in volume?
Baahaaahahahahah.

>>What does this mean? It has a religious ring to it. Energy might work
>>(the point of this thread is to find out), but why should we want to
>>import bulk material from space to Earth? Few extraterrestrial ores
>>match the quality of those found on Earth, save for iron-nickel
>>asteroids, and there's already plenty of steel in landfills. Even if
>>you could import diamonds from the Moon, gold from the asteroids, or
>>star sapphires from Mars, could you beat the transportation costs?
>>Lunar chromium doesn't seem inviting. He3 remains speculative, much
>>more so than SPS. And there is NO market for lunar oxygen on Earth.
>>There might be one in space, but this seems like a circular argument:
>>there isn't, if there's no *other* reason to go into space.
>
>This is a flame and meant to be a flame. If you are so stupid that you do not
>know what this means why don't you pull your head out of the sand and read the
>papers. The Rio summit endorsed only ONE space technology and that was laser
>power beaming from the moon. In case you have not read we are running out of
>almost all of the easily obtainable minerals here on Earth. Don't quote me
>your stupid statistics about percentages in the earth's crust. i know them
>as well as you. What you do not seem to see is that to get at those percentages
>we would have to pollute the world to an extrem extent just to keep up with
>preseent growth in the second world, not to mention the development of the
>third world's standard of living. They want cars and computers and bridges
>just like you in your comfortable American world.  There is a great big
>world out there, wake up to it.

To say that the political posturing in Rio was due to a lot of people
with their head up their ass would be understatement. As Paul Dietz
has shown at length, we are not running out of *any* material that
we need for advanced civilization with the exception of fossil fuels.
And there are ample replacements for them. The Earth is a closed system
except for energy, and even there natural sources are sufficient for
a population ten times the present size *indefinitely*. We have to work
smarter, not harder, to utilize those resources well. Raping the planet
depends solely on our stupidity, or lack thereof, space based materials
won't make a significant difference unless we stupidly continue to be
wastrels, and if we do, they're not going to help long anyway.

>>> This will allow the
>>> Ethopians, our perennial starving masses to irrigate there land and finally
>>> grow enough food to be taken off the planetary welfare roll
>>
>>This assumes an end to the civil war there, which is largely an ethnic
>>conflict. If you can get these people to stop hating each other and
>>peacefully coexist, more power to you.
>
>Abraham Maslow in his text on psychology identified a heirarchy of wants and
>needs. Formost among them is food and shelter.  That is the underlying cause
>of the war in Ethopia at this moment.  The struggle just happens to be
>tribaly not ethnically. Eritrian separtist movement is a tribal movement and
>so are most of the rest in Africa. Food comes before race and you protect your
>family (tribe) first.

I think you might want to take a closer look at the underlying causes
of the Ethiopian civil war. It's not lack of food or shelter, it's
politics at it's most base, like most wars. Like the people of Bosnia,
Ethiopians are quite capable of feeding and housing themselves when they
aren't being bombed and shelled off their lands. The current drought is
part of a cycle that has repeated for thousands of years. In peacetime
the people have coped with this by storing food from the good years to
carry them through the bad. The war has destroyed those traditional
practices, and prevented the humanitarian aid that is rotting on the
docks from being delivered to the people. THIS IS NOT A RESOURCE ISSUE.

>The SPS will help those who want to be helped. It can be used to rasie our
>standared of living without the destructiveness of raping the resources of the
>Earth. I propose that it is wise in your own conceit people like yourself that
>throughout history have played the role of opposition to the future by
>ridiculing the Columbus's, and Wrights and Goddards and VonBrauns of the world.
>
>Part of religion is passion and yes I have a passion for the exploration and
>development of space, not for the sake of that exploration and development
>as and end in and of it self, but for the betterment of the lives of us
>all here on earth.  I sure as heck have not seen your name associated with
>anything doing that.
>
>I don't usually go this orbital on a post like that but somtimes the arrogance
>and presumption of the poster just begs for it.

Sorry Dennis, I support space exploration and space exploitation too, but
I am realistic enough to know it won't make a material difference here on
Earth. Like Columbus' "discovery" of the New World, the riches ultimately
fall to the inhabitants of the New World, not those left behind in the Old
World. So it is with space. People living in space will be the primary
beneficiaries of space activity. Earth can attempt to play Hudson Bay
Company, but eventually Earth has to manage by itself. I don't have a
problem with that as a justification for supporting space. "To boldly go..."
is sufficient reason to support space activities. The human race, wherever
they may be, will be the beneficiaries of that process, not Earthlings.

Gary

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

Date: 12 Aug 92 17:42:24 GMT
From: Mark Evans <[e-mail]>
Subject: Tethers
Newsgroups: sci.space

[e-mail] writes:
: Would it be possible to put something in near orbit over Nevada and
: attach tethers to it so that people could reach the object via
: elevators?  I know it wouldn't be easy, but is there a way to pull
: this off?

read 'The fountains of paradise' bye Clake.

The only way you can get something to orbit above  point of the earth's
surface is to have it in geo-sync orbit.
Thus, the point you have your satellite above must be on the equator.
(if you want it to be over pointelse where on the globe, then it is
not in orbit and must run thrusters virtually continuiously to stay in
position)

Try replacing Nevada with Kenya and you might get it to work.
--
-------------------------------------------------------------------------
Mark Evans                                   |[e-mail]
+(44) 21 565 1979 (Home)                     |[e-mail]
+(44) 21 359 6531 x4039 (Office)             |

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

Date: 13 Aug 92 13:19:53 GMT
From: Dean Adams <[e-mail]>
Subject: Upcoming Delta launches...
Newsgroups: sci.space

 >   SPACE CALENDAR
 >   July 29, 1992
 >
 >   August 1992
 >     20 - GE Satcom C4 Delta Launch

Does anyone know the time/launch window for this flight?

Without it, finding the satellite coverage would be very difficult...

Anyone with info please post or email!

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

Date: 13 Aug 92 10:35:24 GMT
From: Magnus Olsson <[e-mail]>
Subject: Weak interactions, biology and the SSC
Newsgroups: sci.space

Since it has been mentioned several times in the ongoing SSC
debate/flamewar in this newsgroup, I thought I'd just summarize one
possible (very hypothetical) way the SSC results could be important to
biologists:

It is a well-known fact that most biological molecules not only have a
distinct "handedness" (asymmetry under mirror reflection), but also
that all living organisms share the same handedness (all proteins are
built exclusively of the L-forms of amino acids, for example).

It is also a well-known fact that the electromagnetic force
responsible for chemical reactions is parity invariant, i.e. it
don't distinguish between left and right. (it should be pointed out
that this means it has no *intrinsic* handedness - of course an
asymmetric molecule can distinguish between left and right, but then
it's due to the spatial asymmetry of the molecule and not to any
fundamental reasons).


This is normally explained by the fact that all life has a common
ancestor that by pure chance happened to have a certain handedness.
However, why did all "right-handed" life in that case become extinct?

A recent attempt to explain this is the following:

The elctromagnetic force is not the only one acting on molecules.
There is also the weak force, which is - as the name says - extremely
weak. Up to now it has been treated as totally negligible in chemistry.

However, the weak force *does* distinguish between left and right. If,
for example, the nucleus of an atom interacts with an electron by
exchanging a Z boson, the process has different probabilites depending
on the direction of the electron's spin. This could, in principle,
give atoms a very weak handedness. The idea is that this handedness of
atoms would make reactions involving, say, L-amino acids (very)
slightly more favourable than those involving R-amino acids. This
would over geological time scales give "left-handed" life an advantage
over right-handed life.



So where does the SSC enter? Well, the argument is that to understand
the possible chemical effects, we ought to understand the weak
interaction better than today. The SSC will explore the high-energy
behaviour of he weak interaction in ways impossible today (for
example, one would liek to observe the four-Z-vertex).

However, whether this has any relevance to chemistry and biology is
doubtful in the extreme - the influence of weak interactions on atomic
physics and possibly chemistry would of course be a low-energy
phenomenon, and as far as we know, the low-energy behaviour of the
weak interaction is well understood from earlier experiments.

Magnus Olsson                   | \e+      /_
Dept. of Theoretical Physics    |  \  Z   / q
University of Lund, Sweden      |   >----<
Internet: [e-mail]     |  /      \===== g
Bitnet: THEPMO@SELDC52          | /e-      \q

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

Date: 13 Aug 92 12:18:31 GMT
From: Magnus Olsson <[e-mail]>
Subject: Weak interactions, biology and the SSC
Newsgroups: sci.space

In article <[e-mail]> I write:
>Since it has been mentioned several times in the ongoing SSC
>debate/flamewar in this newsgroup

Sorry, but I managed to goof up and post it to the wrong newsgrup - it
should of course have gone to sci.physics, not to sci.space. Sorry for
wasting your bandwidth (and this accursed NNTP server won't let me
cancel my own articles...)

Magnus Olsson                   | \e+      /_
Dept. of Theoretical Physics    |  \  Z   / q
University of Lund, Sweden      |   >----<
Internet: [e-mail]     |  /      \===== g
Bitnet: THEPMO@SELDC52          | /e-      \q

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

Date: Thu, 13 Aug 92 12:07:06 BST
From: [e-mail]
Subject: Why is this on SpaceDigest (or sci.space)

I really don't see the reason for the massive list of cross postings.
If you are going to relate this to how societies approach space, or
the formation of extraterrestrial politico-economics systems, fine.
But this seems more like a straight poly-sci argument.

Be more selective in your cross-posting.

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End of Space Digest Volume 15 : Issue 106
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