Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v15_0/v15no091.txt

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Date: Mon, 10 Aug 92 05:02:57
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #091
To: Space Digest Readers
Precedence: bulk


Space Digest                Mon, 10 Aug 92       Volume 15 : Issue 091

Today's Topics:
                            Energia, Zenit
           Energiya's role in Space Station assem (3 msgs)
                           Followup attempt
                    Gravitational slingshotting...
                      Hobbled Space Telescope...
                      Home made rockets (4 msgs)
                        Seeding Mars with life
                      Soyuz-Progress data (long)
                       SPS and light pollution
             SPS feasibility (WAS: SPS fouling astronomy)
                        SPS fouling astronomy

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Date: 9 Aug 92 23:19:17 GMT
From: John Roberts <[e-mail]>
Subject: Energia, Zenit
Newsgroups: sci.space

-From: [e-mail] (Chris Jones)
-Subject: Re: Energiya's role in Space Station assem
-Date: 9 Aug 92 16:07:06 GMT
-Organization: Kendall Square Research Corp

-In article <[e-mail]>, henry@zoo (Henry Spencer) writes:
->Energia (two stages) and its strap-ons (one stage) have a flawless record
->as far as I know.  The one Energia failure was a payload engine failure.
->Unless I've missed one, all the Tsyklon failures have been upper stages.

-As I recall (having myself made this identical mistake in the past), Energiya's
-boosters are Zenit first stages, not Tsiklon (both are Ukraine-manufactured, I
-believ).  One Zenit failure caused extensive pad damage, so it must have been a
-first stage.

Yeah, it was the Zenit I was thinking of. I believe there have been at least
two recent failures, including at least one launch-pad explosion. I vaguely
recall comments at the time that the Zenit is the Energia booster.

Hm, when in doubt, look through Henry's AWST summaries:
..................

>From: [e-mail] (Henry Spencer)
Subject: space news from Sept 9 AW&ST
Date: 9 Dec 91 01:03:11 GMT

Soviets face serious setback as Zenit booster explodes at low altitude.
Payload was reportedly an eavesdropping satellite.  This is the second
Zenit failure in a row at Baikonur; this one was preceded by persistent
technical problems that led to swapping the original booster for a backup
Zenit.  It's bad news for budget pressures on the Soviet space program,
for the Energia/Buran program (since the Energia strap-ons are Zenits),
and for international marketing of Zenit.  Cause is not definitely known
yet; the previous Baikonur Zenit failure has been attributed to an oil
leak in the engine system causing engine shutdown a few seconds after
liftoff.

>From: [e-mail] (Henry Spencer)
Subject: space news from Sept 23 AW&ST
Date: Wed, 29 Jan 1992 05:12:44 GMT

More on the Aug 30 Zenit failure:  apparently the second stage blew up
during or following second-stage ignition.  This is significant because
it means this failure does not affect the Energia strap-ons, which use
only the first stage.

>From: [e-mail] (Henry Spencer)
Subject: space news from Dec 16/23 AW&ST
Date: Wed, 11 Mar 1992 02:44:47 GMT

Turmoil in the Soviet space program due to political confusion and
funding shortages.  Notably, the Ukraine has terminated production of
the Zenit, citing a cutoff of Russian funding and the lack of benefits
to the Ukraine.  Most other space activities are continuing, since they
were largely based in Russia, but the pace has slowed, with launch
operations at their lowest level in 25 years.

..................

So it looks like *maybe* the Energia booster portion was not responsible
for the second explosion, but the first explosion *does* appear to be the
fault of that booster.

(By the way, Henry, thanks for those AWST summaries. I know you don't like
to save most of your old posts, but somebody ought to put together a CD-ROM
"The Wisdom of Henry Spencer". On second thought, make that a *series*
of CD-ROMs. :-)

John Roberts
[e-mail]

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

Date: 9 Aug 92 20:57:04 GMT
From: Henry Spencer <[e-mail]>
Subject: Energiya's role in Space Station assem
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:
>>High though my opinion of the Saturn V is, anyone who calls the first
>>Energia launch a failure would have to work real hard to call the second
>>Saturn V launch a success.
>>--
>Care to elaborate on that Henry? I don't recall a failure or even near
>failure of the system...

You're obviously not recalling very hard. :-)  The second Saturn V had
abundant problems.  Pogo oscillation in the first stage was actually not
terribly surprising, because that is fairly common in new rockets,
and indeed it was present (although weaker) on the first Saturn V too.
However, +-10G at 5-6Hz is still pretty nasty, even if it only lasts 10s!

Then pieces of the spacecraft adapter (which on a real mission would
have had a LM inside it) tore away.  Structural failure in the adapter
honeycomb, independent of the pogo despite the timing.

Then, four minutes into second-stage flight, engine 2 misbehaved badly
and shut down... followed immediately by engine 3 abruptly shutting down.
Engine 2 had a fuel leak and fire, and some of the shutdown commands
for it went to engine 3 due to a wiring error; none of this was known
until weeks afterward.

A double shutdown of adjacent engines hadn't been studied much; the
studies that had been done said "booster will tumble out of control,
destroy it", and that's what the mission rules said to do.  Bob Wolf held
off momentarily, saw that nothing so bad was happening, and let it go.
The burn was extended to use up the remaining fuel, and things were more
or less okay until staging.

The third stage started out deciding it was too high (because the engine
failure had put the second stage off course), then it decided its angle
was too low and pitched up again, then it decided it was going too fast.
When it achieved orbit and shut down, it was actually thrusting backward.
The resulting orbit was elliptical, not the circular one that had been
planned.  And there were signs of engine abnormalities starting midway
through the burn.

Then they tried to restart the third stage to simulate translunar injection,
and it refused completely.  Same problem as engine 2 on the second stage,
as it turned out.

Had there been a crew aboard, the flight would unquestionably have been
aborted during the pogo.  If not then, then on the double failure.  And
if not then, then during the third stage's confusion.  Although a crew
would have survived and many of the mission objectives were salvaged by
some improvising, this was *not* a successful flight.  It took a major
investigation to solve the problems.  Putting a crew on the very next
flight was more than a little daring, and might not have been done if
time (late 1968) and competition (strong signs that a Soviet circumlunar
manned mission was imminent) hadn't been pressing.
--
There is nothing wrong with making      | Henry Spencer @ U of Toronto Zoology
mistakes, but... make *new* ones. -D.Sim|  [e-mail]  utzoo!henry

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

Date: 9 Aug 92 22:03:04 GMT
From: Gerald Cecil <[e-mail]>
Subject: Energiya's role in Space Station assem
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Chris Jones) writes:
>To date, all (both) flights of the Energiya used two strap-on boosters, I
>believe.

You may be right about flight #2 w/ Buran ... I'll look for pictures
tomorrow.  But pre-launch & launch photos of the 1st flight of Energiya
(eg. pp. 163, 166, & 176 in The Soviet Manned Space Program by Phillip
Clark 1988, ISBN 0-517-56954-X) clearly show 4 strap-ons, paired 2 to
a side; p. 176 shows 3. Interesting that all these pictures omit the
quadrant occupied by the 3rd-stage cargo pod, supporting rabid statements
that it was an ELINT satellite lost by (as Clark writes) ``human error''.
(Although it seems strange to me that they'd put this on the test flight
of a new booster.) Anyone know of a picture that shows the 3rd stage? The
1st stage of the SL-16 medium lift vehicle uses the RD-170 engines of
Energiya's strap-ons, and is designed to replace the Proton.  Clark
states that the SL-16 has different engines than the Tsyklon (SL-11 and
SL-14), but this is attributed to private conversations with ``officials''.
--
Gerald Cecil 919-962-7169  Dept. Physics & Astronomy
U of North Carolina, Chapel Hill, NC 27599-3255 USA
-- Intelligence is believing only half of what you read; brilliance is
   knowing which half. ** Be terse: each line cost the Net $10 **

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

Date: 10 Aug 92 03:58:00 GMT
From: [e-mail]
Subject: Energiya's role in Space Station assem
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Henry Spencer) writes...
>In article <[e-mail]> [e-mail] writes:
>>>High though my opinion of the Saturn V is, anyone who calls the first
>>>Energia launch a failure would have to work real hard to call the second
>>>Saturn V launch a success.
>>>--
>>Care to elaborate on that Henry? I don't recall a failure or even near
>>failure of the system...
>
>You're obviously not recalling very hard. :-)  Henry Henry Henry. To me

[Henry's account of the second Saturn mission deleted]

your little narrative is indicitive of a very robust system under great
stress that STILL reached orbit and would have ended up with live astronauts
or an intact space station module.  The Energia's problem on the other hand
ended up with its payload as an artificial reef. That to me justifies the
title of successful. By the way the problems with the J2 which was the
culprit was fixed and tested on a Saturn 1B launch before the stack was
reflown on the Saturn V for the first manned launch of the system.  If I
remember correctly, the astronauts on the first manned flight complained
greatly about the pogo problem which was largely solved by adding some
piping down near the engines that changed the resonant frequency of the
pogo.  Just to be honest however, the problem of the lost heat shield and
the left solar array was caused by a resurgance of the pogo problem when the
Saturn was reconfigured for the Skylab mission. That is one reason why I am
cynical about Allen's presto bango approach to answering all of the questions
about HLV's and Soyuz's. He has already made so many modifications that both
vehicles are barely recognizable AND he still has not answered the assertion
that the Shuttle will become more and more important as the transfer of
payload becomes a two way event becomes more and more common.

Dennis, University of Alabama in Huntsville

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

Date: Sun, 9 Aug 92 16:54:39 -0500
From: [e-mail] (Phil G. Fraering)
Subject: Followup attempt

>Waddabout WD40?  No self respecting handyman would be without it!

>On the serious side, anybody know how this miracle drug of mechanics works
>in the space environment?

Hmmm... I thought the free-fall enviornment was one of the main drivers
behind the use of teflon in lubricants.

You'd probably want to use DuPont Tri-Flow. It's what I use when
I get serious about lubrication. I with I had antimatter so I could
get serious about housecleaning...

--
Phil Fraering [e-mail] where the x is a number from 1-5.
Phone: [phone]
"There are still 201969 unread articles in 1278 groups" - nn message

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

Date: Thu, 06 Aug 1992 23:40:00 +1000
From: Jason Lingohr <[e-mail]>
Subject: Gravitational slingshotting...
Newsgroups: sci.space

I need someone to help me with some information I need really quickly regarding
the technique of "slingshotting" satellites between planets.  The same technique
used (at least) by both Voyager probes.

I need technical information, ie. formulae for the calculation of angles,
resultant velocity and/or propelling distance, all that sort of stuff.

And some history on the actual conception and usage of the technique would be
indeedly most helpful.

Please email me at [e-mail] with absolutely anything you have.  And
quickly if at all possible.  Thankyou!!



+----------------+---------------------+------------------+------------------+
|  ___           |    Jason Lingohr    | "Where ya from?" | "Hey! Someone    |
| (   >          |                     | "Australia"      | spiked my beer   |
|  __/___.  _    | [e-mail] |                  | with alcohol!"   |
| / / (_/|_/_)_  |                     | ... "Where?"     |                  |
|<_/             |    "The LingMan"    |                  |   - A cab driver |
+----------------+---------------------+------------------+------------------+

 * Origin: What ever happened to WOCin??? (3:632/998.200)

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

Date: Sun, 9 Aug 92 17:04:30 -0500
From: [e-mail] (Phil G. Fraering)
Subject: Hobbled Space Telescope...

\Also they will be upgrading the onboard computer system to something
/approaching a real computer including a 386 processor.  That will be a big
\help.

To paraphrase Arthur Dent, this must be some new definition of the
word computer with which I was heretofore unaware.

I know, according to Turing's theorem, all algorithmic devices, like
abacuses and analytic engines and 386's are considered to be of the
same basic type as Crays and Amigas, but still...

--
Phil Fraering [e-mail] where the x is a number from 1-5.
Phone: [phone]
"There are still 201969 unread articles in 1278 groups" - nn message

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

Date: 10 Aug 92 01:22:46 GMT
From: "Frederick A. Ringwald" <[e-mail]>
Subject: Home made rockets
Newsgroups: sci.space

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

> True. But I'd be happy to sign a liability release if it would let me watch
> a Shuttle launch from a mile or two away.

In that case, your eardrums may not be too happy with you. I saw the
Skylab I launch from Titusville, right across the bay, and that was
PLENTY close enough! (It's a low-frequency sound much more felt than
heard.)

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

Date: 8 Aug 92 22:10:07 GMT
From: "Steve J. Quest" <iowegia!quest>
Subject: Home made rockets
Newsgroups: sci.space

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

> In article <[e-mail]>
> [e-mail] writes:
>
> > I have recently got into the field of making home-made rockets and have
> > been experimenting with various types of cheap, readily availible fuels and
> > cannisters.
> [...]
> > Launch sites have
> > proved to be a bit of a problem as with the current state of political
> > affairs here, we are a touch scared of being arrested.
> >
> > If anyone has any new/different ideas for fuels, chemical components,
> > homemade flares, please let me know.
>
>
> Please DO NOT DO THIS, for the sake of your safety and the safety of
> everyone around you. This is a very good way to get KILLED or SEVERELY
> MUTILATED.
>
> I know a former bass player and chemistry enthusiast who was making his
> own solid rocket engines. He blew off all the fingers on his right
> hand. I think he's wised up about homemade rockets/explosives
> manufacture, often known as "basement bombing." He doesn't play bass
> any more, either: can you guess why?
>

Fred,

        I think you are broadbrushing a might when you say that
nobody can safely manufacture their own engines.  Daily I work
with high power optical radiations, and the lethal high voltages
associated with their production.  Needless to say, safety is
something I am always thinking about.

        I also used to manufacture my own engines as a kid.  The
best all purpose "cheap" fuel I came up with was "Black Jack
Roofing Tar" mixed with Potassium Chlorate as the oxidizer.
Memory doesn't serve me as to the volumetric mixture, but I do
remember (and can hypothesize) that the oxidizer outweighed the
fuel (tar).  I used fired clay nozzles (ceramic, per se) and
aluminum engine casings.  Deployment was electronic on my rockets,
many of which had radio transmitting beacons.  THIS WAS SOMETHING
THAT I DEARLY LOVED TO DO!  Of course Mommy and Daddy thought I
was a menace, but I never hurt anyone, nor did I ever have an
accident.  Safety features were built into all of my rockets with
40 kilo or greater fuel loads.  I had fun back then, and I spent
hundreds of dollars on what I call an education in rocketry- REAL
model rocketry!

        If someone comes up to me and asks me how to make engines
for experimental rockets, I will be more than happy to help them -
provided that they make SAFETY a primary concern.  You can tell if
a person is capable of the task just by talking with them.  If
someone were to say that they were going to commit acts of
terrorism, or were going to have explosive payloads (explosives
designed to do outward destruction, more than those used to
destroy a renegade rocket by blowing out the nozzle for example)
are people who I would NOT help.  One can only have fun in science
if they are able to grow beyond the preset limits that government
or society set.  So long as safety is considered, I believe in
going beyond those bounds.  Daily I step beyond the bounds, but
not outside the guidance of the CDRH, and this is for the growth
of science...........sq

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

Date: 8 Aug 92 22:41:11 GMT
From: "Steve J. Quest" <iowegia!quest>
Subject: Home made rockets
Newsgroups: sci.space

[e-mail] (John Roberts) writes:
> Again, back in the old days, the recommended mix was powdered zinc and sulfur
> I can find you a reference to an old Air Force book on model rockets, if you
> like. Don't forget the sandbags around the fuel press, the square miles of
> safety range, the sunken launch pad, the safety observers, the concrete
> bunker,.... :-)
>
> I can't do anything about the local laws. Maybe you can get yourself declared
> an experimental rocket institute. :-)
>
> You may get the impression from all this that building rocket engines is
> an extremely difficult and potentially dangerous undertaking, that should
> only be attempted with extreme care, concentration, and observance of the
> local laws. That is a correct impression.
>
> John Roberts
> [e-mail]


John,

        The most "interesting" powdered metal fuel I came up with
was a mixture of powdered magnesium, amorphic carbon dust, and
ammonium perchlorate.  Later I substituted aluminum powder because
of instability of storage for the magnesium in a finely divided
state (the magnesium oxidized in storage).  Thrust was INCREDIBLE
and I was able to launch my heaviest payloads with this fuel.
Mechanical guidance was required, as usual with long fuel burns.
Night launches were spectacular, as you would get a column of
white fire at least 5 times longer than the rocket itself....sq

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

Date: 8 Aug 92 22:49:43 GMT
From: "Steve J. Quest" <iowegia!quest>
Subject: Home made rockets
Newsgroups: sci.space

[e-mail] (Henry Spencer) writes:
> I'd revise that slightly:  if you're not a pro, don't try it unless you
> are prepared to turn yourself into at least a semi-pro first.  Study the
> field rather than trying to just blunder ahead on your own; pros know
> that it's not an easy job, and are grateful for all the help they can get.
> Take precautions against damage to equipment (minor), yourself (serious),
> or innocent bystanders (awful damn serious, especially in a country like
> the US that has let its liability lawyers go berserk); pros know that
> explosions and other violent failures are a normal part of rocket-engine
> development, and that a small quantity of explosives (e.g. rocket fuel)
> will produce a much bigger explosion than most laymen think.  Plan for
> thorough testing under varied conditions before trying to use the engine
> "for real"; pros know that having it work once or twice doesn't mean it
> will always work under those conditions, never mind others.


Henry,

        One thing I feel I should mention to add to your comments
is; you should ALWAYS test new engine designs by bolting them to a
stationary (horizontal) test stand, and fire them with shielding
all around them (sufficient to absorb any fragments that might fly
off an exploding prototype.

        I did fancy things like measure the thrust with a
kilo-newton gauge fashioned onto the spring loaded test stand.  I
also made sure anything that might blast out the back (or front)
of the engine was blocked by heavy concrete blocks- with hay bales
on the side for shrapnel protection.  Three tests of the engine
design were enough for me- then I flight tested them.........sq

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

Date: 9 Aug 92 23:42:52 GMT
From: John Roberts <[e-mail]>
Subject: Seeding Mars with life
Newsgroups: sci.space

-From: [e-mail] (David Knapp)
-Subject: Re: Seeding Mars with life
-Date: 9 Aug 92 15:37:30 GMT
-Organization: University of Colorado, Boulder

-In article <[e-mail]> [e-mail] (Kenneth Tolman) writes:
->
-> It appears that with today's technology an attempt to begin terraforming
->Mars could begin now.

-I think introducing *any* life, intentionally or nonintentionally, to the
-Martian system would be a *huge* mistake, until we have studied the hell out
-of Mars.

-Luckily, the world's space agencies have decided on an agreement that forbids
-the introduction of nonsterilized spacecraft until into the next century, when
-we will perhaps have done more exploration.

A few days ago, I posted the Planetary Protection requirements for Mars
Observer, which apply to an unsterilized spacecraft intended to orbit but
not land on Mars. Does anybody have the equivalent requirements for a
lander?

I presume the Viking landers were sterilized, otherwise their tests for
Mars life would have been meaningless. There's been at least one crash of
an unsterilized spacecraft, but perhaps that won't do too much harm.

One major problem for life on Mars that has been discussed by experts is that
near enough to the martian surface to take advantage of solar energy, there's
enough hard UV radiation and chemically active soil to kill just about any
active Earth life. That's why the proposed searches for Mars life mainly
involve fossil remains of life and perhaps dormant life underground, left
over from when conditions were more favorable.

John Roberts
[e-mail]

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

Date: Sun, 9 Aug 92 17:12:59 -0500
From: [e-mail] (Phil G. Fraering)
Subject: Soyuz-Progress data (long)

\In article <[e-mail]> [e-mail] (Dennis Newkirk) writes:
/>The capsule was designed to perform ballistic reentry from lunar
\>distances which resulted in from 10 to 16 gravities.

/If reentry from LEO results in accelerations anywhere near
\as high, it appears that Soyuz is unsuitable for safe return
/of an ill person from orbit.  A lifting capsule is required.

Wait a sec... wasn't the Soyuz tested in lifting capsule mode for
the lunar missions? Didn't the Zond capsules perform lifting re-
entries?

Remember folks, the Zonds, which circled the moon, were just
unmanned (although some people, in strictest private confidence,
wonder about that part) Soyuz variants...

\--
/    "And I don't think cripples, gays or Jews make particularly good
\citizens.  Killing them is a positive moral good to the human race and
/to the planet." -- Steve Arnold, <[e-mail]>,
\his entire text, later disclaimed; sarcasm, or Freudian slip?  You decide.

I'll go for unattended terminal myself....

--
Phil Fraering [e-mail] where the x is a number from 1-5.
Phone: [phone]
"There are still 201969 unread articles in 1278 groups" - nn message

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

Date: 10 Aug 92 00:55:44 GMT
From: "Frederick A. Ringwald" <[e-mail]>
Subject: SPS and light pollution
Newsgroups: sci.space

In article <[e-mail]>
[e-mail] (R. Cage) writes:

> Ground-based solar is available only during daylight, and has
> seriously reduced availability in the winter months at higher
> latitudes.  This requires long-distance transport or long-term
> energy storage, which would be real nice to have anyway; we
> don't.

Yes, we do. It's called pumping water uphill, and power companies have
been doing it for years. Transport is not helped by SPS, because
transmission losses are the same.

> SPS is there almost all the time, and its out-periods
> are quite predictable (and at low-demand hours, too).  Wind
> is also quite irregular.

On the average, meaning on the average, it's remarkably predictable.
It's also largely unharnessed, especially in midwestern states such as
the Dakotas. See the recent Scientific American article and references
therein, if you don't believe me.

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

Date: 10 Aug 92 00:46:25 GMT
From: "Frederick A. Ringwald" <[e-mail]>
Subject: SPS feasibility (WAS: SPS fouling astronomy)
Newsgroups: sci.space

Again, kindly supply numbers and literature references. Otherwise, how
can I tell if your arguments aren't just anecdotal?

Laser transmission from the Moon takes care of sky brightness and radio
static problems, but still leaves atmospheric heating open. (It also
dispenses with a traditional geostationary SPS advantage, perpetual
power transmission, but this is relatively minor: power companies today
store enormous amounts of reserve power by pumping water uphill.)

Most seriously, too, it has not addressed the issue of cost.

> although to carry your analogy to its logical
> conclusion we must turn off all of our lights at night and quit buring
> fossil fuels due to the degradation it causes to astronomy.

That's taking it to its logical extreme, a little different from taking
it to its logical conclusion, but it'd suit me fine, all the same.

> Yes it will mean a greatly increased standard of living for a variety of
> reasons.

Again, WHAT reasons? Electric cars do not require SPS for their
development.

> 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.

> 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.

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 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.

Fred Ringwald
Department of Physics & Astronomy
Dartmouth College
Hanover, NH 03755-3528

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

Date: Sun,  9 Aug 92 13:49:58 PDT
From: Andrew - Palfreyman <[e-mail]>
Subject: SPS fouling astronomy
Newsgroups: sci.space

Dennis writes:
: PS I did not mention that the laser based SPS system could be used in Africa
: to bring electical power to areas that do not nor will not have an electrical
: power generating infrastructure unless it is from SPS.  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 goes for
: hundreds of uses of energy in all of the third and fourth world.  This will
: have the benefit of saving lives and bringing political stability to areas
: of the world that sorely need it.

..and reducing debt, cutting the population growth curve and salving
first world consciences into the bargain.

This futuristically global argument reminds me of the James Burke idea
of the Carbon Ration system he proposes in the epilogue to his "After
The Warming" documentary. Whether the idea is technologically sound I
leave to the Spencers, Dietzs, Szabos, Coffmans and Sherzers.

I would greatly like to see an idea like this have its day. The
consequences of its implementation would be an enormously positive
contribution to global quality of life. If it worked.

Returning to Burke's "tit-for-tat" 1st-3rd world trading scheme,
it strikes me that something similar could be applied to Dennis'
scheme also. The basic idea is to offset the projected future costs
of 3rd world aid against provision of the technology to these 3rd world
countries, financed by the 1st world on some kind of credits
system. There is a whole mess of complexity in this simple concept,
but it sounds vaguely workable.

This sounds like something that is unique to space and of inestimable
benefit. For these reasons, I'm sure it won't work. :-)
 --------------------------------------------------------------------------
| lord snooty @the giant | Would You Like Fries With That?                 |
| poisoned electric head |              [e-mail] |
 --------------------------------------------------------------------------

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Date: 
P
From: 
P
Newsgroups: sci.space

From: "Allen W. Sherzer" <[e-mail]>
Subject: Re: Comments, Misc
Message-Id: <[e-mail]>
Organization: Evil Geniuses for a Better Tomorrow
References: <[e-mail]>
Date: Sun, 9 Aug 1992 21:02:08 GMT
Lines: 82
Sender: [e-mail]
Source-Info:  Sender is really [e-mail]

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

>Allen, this is the text of the email I have been trying to send
>My apologies to the net, but my mail server (or my comm program) has
>been acting up.       Hi Allen!

No problem.

>    Could you please stick my name and address on the space
>activists mailing list, please.  I hope this email makes it through

Your on the list. Anybody else wishing to join, send mail to:
[e-mail] or to me.

>> I don't think we need to. We can stick some Shuttle tiles on it,
>>put a parachute on top, and teather it down

>     Whoosh!  You're kidding, I hope.  Controlled reentry is a
>tricky business, unless you're willing to take the Soviet
>"hypersonic cannonball" approach by using a sphere and accepting a
>dispersion (2 sigma) of about +/- 30 miles.

Sure it is a little more complex than that but it isn't the trillion
$$ billion year effort others claim.

As to the dispersion, sure I'll accept that. We drop it in South Texas.
Saving a couple of billion per year is worth a little hiking.

>     To get a reasonable reentry (no fine guidance, just enough
>control to maintain attitude and control to avoid tumbling or
>excessive entry heating), you'll need a RCS plus some type of
>aerodynamic control to maintain attitude after separating from that
>tether.

OK we will do it. How much will it cost? A billion? Two? Five? It's
still worth it.

>[Note:  nominal reentry interface is about 400,000 feet --
>about 75 miles altitude.  The tether has to be 175 miles long, or
>else you'll need some attitude control after letting go.]

If needed. If not practical, I can think of alternatives.

>    Furthermore, a logistics module is rather unsuited for reentry -
>the c.g. is way off from the c.p., which either means a ferocious
>control system (huge fins or one mother of a RCS) or you'll have to
>redesign to redistribute the mass.  Not cheap.

If needed, we redesign. It will be cheap compared to the alternative.

>    The structure also isn't strong enough to take a parachute
>landing impact.

We are talking about a redesign. I would base it on the DC-X or HL-20
designs. If needed, we will put a kick motor on the bottom to slow it
down like Soyuz.

>seconds late.  At orbital velocity, timing errors can really throw
>the system off.  A one minute error translates into about 277 miles.

So we land in South Texas. Another poster has pointed out that Soyuz
can land in water.

>>>Your point about the single point failure is well taken, however,
>>>four crewmembers simply cannot fit inside a Soyuz return module.

>> They can for the short time needed to get to the other one.

>   Errr.... beg to differ here.

They fly with three so there must be room for a forth in the Orbital
Module. However, if I am wrong, then two or three retrieve the other
Soyuz and return to get the fourth person. Still much safer than the
single point failure possible with ACRV.

   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?"                               |
+----------------------257 DAYS TO FIRST FLIGHT OF DCX----------------------+

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End of Space Digest Volume 15 : Issue 091
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