home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Space & Astronomy
/
Space and Astronomy (October 1993).iso
/
mac
/
TEXT
/
SPACEDIG
/
V16_1
/
V16NO180.TXT
< prev
next >
Wrap
Internet Message Format
|
1993-07-13
|
32KB
Date: Sun, 14 Feb 93 04:59:59
From: Space Digest maintainer <digests@isu.isunet.edu>
Reply-To: Space-request@isu.isunet.edu
Subject: Space Digest V16 #180
To: Space Digest Readers
Precedence: bulk
Space Digest Sun, 14 Feb 93 Volume 16 : Issue 180
Today's Topics:
A response from Anonymous
Getting people into Space Program! (2 msgs)
Homework (was Re: 1st lady Yank)
HST repair mission
ideas on reviving the SSF project as well as Mir
kerosene/peroxide SSTO
Other shuttles (was Re: Getting people into Space Program!)
Question Help !
Russian Space Mirror
Sabatier Reactors.
Spaceships made of ice: some lighthearted speculation (2 msgs)
space station cut, goldin to stay on at NASA
SSTO news
Women in EVA (was Re: Question Help !)
Welcome to the Space Digest!! Please send your messages to
"space@isu.isunet.edu", and (un)subscription requests of the form
"Subscribe Space <your name>" to one of these addresses: listserv@uga
(BITNET), rice::boyle (SPAN/NSInet), utadnx::utspan::rice::boyle
(THENET), or space-REQUEST@isu.isunet.edu (Internet).
----------------------------------------------------------------------
Date: Sat, 13 Feb 1993 15:50:39 GMT
From: 8 February 1993 <an8785@anon.penet.fi>
Subject: A response from Anonymous
Newsgroups: news.admin.policy,alt.privacy,comp.org.eff.talk,sci.space,sci.astro
While the reactions in this newsgroup is slightly
more subdued, the effect is virtually the same
as the torch-bearers storming the castle in
sci.space -- a several contributors here think that
banning anonymous posts to technical groups
is a good idea.
Why is this? Certainly most readers are adult and
are able to hit 'N' (or whatever on VMS systems)
when reading material they find 'incorrect' or, in
their opinion, tasteless.
Do you want to prevent other readers of the
newsgroup from being able to make the same
choice? Why do you have the right to enforce
others' viewing habits when we don't control
the length or content of _your_ .sig?
No. I think the fundamental issue here is control.
Some Usenet contributors are afraid of losing
control over others who disagree with them,
especially disagree with them in way they don't
understand, such as tasteless satire, seemingly
off topic references and other drollery. It
doesn't seem "quite right" to them: it's the
Hofstadter's cartoon character tweaking them
from another frame.
The controllers don't know what to do with it, so they
become anxious, posting notes to this group on the
'inherent evil' of anonymous postings.
What is the evil? I am responsible. That is, I will
response to sensible questions or comments. I am
also accountable: if I post passwords or Secret
Research Plans, the administrator of penet.fi
will surely turn his e-mail racords over to the
authorities. Even if I simply do crimes such as
"denial of service" by posting excessively or such,
I can ultimately be made accountable. So, again,
what is the *real* problem?
Is the problem that some are used to "punishing" posters
who are upsetting in some vague way by complaining
to the (usually acquiescent) sysadmin or organizations
that the poster belongs to? That surely is the most
gutless approach to solving problems, but my
experience on the net shows that the same users
who vilify anonymous postings are the first to
write obsessively detailed grievances to the poster's
supervisor when his or her tranquility is disturbed
by some "intrusive" or subversive post or another.
Anonymous postings prevent just this kind of intimidation.
It is the logical extension of not knowing the sex, race,
religion, or age of the poster (which of course the
racist or rigid right-wing apologist finds extremely
disturbing. After all, not knowing the sex of the
contributor means that I can fit them in to my
overall scheme of "what to say in front of a lady
engineer" or other such tripe.)
The poeple who decry anonymous postings are the
real desperadoes who fear for the stability of
their gang cartels. Of *course* they fear the
introduction of the anonymous Colt, the great equalizer.
The settling of cyberspace will require new habits
of thought from the hierarchicalists: thoughts as
expressed as postings are to be judged by content
and internal merit, if any, rather than on the trappings
of affiliations or other hoopla or fanfare.
........................................
Warning: this is an anonymous posting. If pasted into a TCB or Security Kernel
incorrect results may occur. Meta-level criticism of anonymous postings will
be answered provided the sender: (1) supply C3 level authentication of
identity, including social security number, driver's license number, verifiable
home address and phone number and home phone numbers of two higher-level
supervisors. (Spouse's phone number and place of employment may be
substituted if self-employed); (2) supply MD5 level or greater authenticating
signature of contents accompanied by the oath of two Notary Publics of the
correctness of the preceding information under penalty of perjury under the
laws of the State of California and New York.
The reader acknowledges the copyright of the original message remains with
an8785. Copyright (C) 1993 an8785. All Rights Reserved. Unauthorized
excerpting or reposting may subject the infringer to severe criminal and
civil prosecution under the (S.893) Federal Software Copyright Law or the
Electronic Communication Privacy Act, or both. (For purposes of the FSCL,
the retail value of each message or posting by an8785 is valued at a
minimum of US$2,501.)
Responder agrees that copyright of response becomes the exclusive property
of an8785 and that all responses may be sold, assigned, published, made
public, and/or sent to members of any law enforcement body or private citizen.
Responder agrees that by responding to this message, he or she permits and
explicitly solicits indecent, obscene, or abusive messages by return e-mail.
"NOTICE: This is a private data stream. All responders to this stream are
subject to having their activities audited. Anyone using this stream consents
to such auditing. Unauthorized or illegal responses revealed by auditing may be
used as evidence and may lead to criminal prosecution."
Responder agrees to indemnify recipient and to pay all attorney's fees in
case of prosecution or litigation for whatever reason. To unconditionally
agree to all the above conditions, press any key.
-------------------------------------------------------------------------
To find out more about the anon service, send mail to help@anon.penet.fi.
Due to the double-blind system, any replies to this message will be anonymized,
and an anonymous id will be allocated automatically. You have been warned.
Please report any problems, inappropriate use etc. to admin@anon.penet.fi.
*IMPORTANT server security update*, mail to update@anon.penet.fi for details.
------------------------------
Date: 13 Feb 93 03:07:57 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Getting people into Space Program!
Newsgroups: sci.space
In article <C2CD42.FnB.1@cs.cmu.edu> nickh@CS.CMU.EDU (Nick Haines) writes:
>In article <rabjab.6.729466605@golem.ucsd.edu> rabjab@golem.ucsd.edu (Jeff Bytof) writes:
> In article <C2AMws.KBn@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes:
> >From: henry@zoo.toronto.edu (Henry Spencer)
>
> >The Russian Space Agency, for that much hard currency, would happily
> >build and launch three of them (one as a demo to prove they could do
> >it -- since the US wouldn't believe them otherwise -- one for operational
> >use, and one as an on-orbit spare), and throw in free maintenance and
> >resupply for the first five years.
>
> Here we go again. Wouldn't throw Americans out of work?
>
>Yes, it would, in the short term. But look at it from an international
>perspective. The former Soviet Union is on the brink of chaos. Four
>states (Russia, Ukraine, Belarus, Kazakhstan) have nuclear weapons on
>their soil. In Russia itself (hardly a stronghold of democracy just
>yet) the economy is weaker than ever; regions and cities are declaring
>autonomy; the whole country is becoming splintered. Why? Because
>they're critically short of hard currency and jobs. Scientists,
>engineers, and specialists (the very people who might get it back on
>its feet) are leaving in droves. People are starving to death in
>modern Russia; it is not far from a descent into anarchic feudalism.
>An anarchic feudalism with a very large nuclear arsenal.
>
>Don't you think that boosting the economy, giving jobs to these
>scientists and engineers, restabilising the government, _and_ buying a
>suite of international space stations, is worth $4bn? Compared to
>lining the pockets of NASA contractors (which is _all_ that $4bn would
>do over here; it won't buy you diddly). Think about the possible
>outcomes:
>
>(1) a new, large and rapidly growing trading partner (read: market for
>American goods), with obligations to the US for bailing it out;
>
>(2) a large assortment of poor and fiercely nationalist statelets
>(some Islamic fundamentalist, some Communist, some just plain
>anarchies), with lots of nuclear weapons and a grievance against the
>US (namely: the US outspent them, ending the cold war and plunging
>them into this situation -- and if you think this feeling doesn't
>exist in Russia you're very wrong).
>
>I'm not saying the US should `invest' in random shoddy tractor parts
>or something; I'm saying money should be spent on those things the
>Russians do _better_ and _cheaper_ than the US, and that the rewards
>will be _both_ a better space program _and_ a better international
>situation.
As the owner of a Belarus tractor, I'd say they make _better_ and
_cheaper_ tractors than us too. They are simple, strong, and easily
maintained.
Now to the arguments about financing the ex-Soviet aerospace industry.
About the only more inefficient way of stimulating the ex-Soviet economy
than buying their aerospace products would be direct foreign aid government
to government. The *best* way to stimulate the ex-Soviet economy is to
purchase lower tech items in large quanity. This rapidly spreads the wealth
to the public and small enterprises rather than concentrating it in the
hands of a few ex-government high tech enterprises with relatively
small payrolls. What the ex-Soviet system needs most desparately
is *not* concentration of wealth into the hands of a few, they've
had that for generations. What they need is a general spreading
of wealth into the entire productive sector.
On another note. Even though the ex-Soviet economy is smaller than
ours, $4 billion is still a drop in the bucket unlikely to make a
critical difference in their market's survival.
Gary
--
Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary
Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary
534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary
Lawrenceville, GA 30244 | |
------------------------------
Date: 12 Feb 1993 22:01:21 -0500
From: Pat <prb@access.digex.com>
Subject: Getting people into Space Program!
Newsgroups: sci.space
In article <1993Feb10.181803.5203@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes:
>In article <1993Feb10.022228.17108@iti.org> aws@iti.org (Allen W. Sherzer) writes:
>>In article <1l90piINNpum@phantom.gatech.edu> matthew@phantom.gatech.edu (Matthew DeLuca) writes:
>
>An airliner takes 22 hours to get to Australia while it's wings do the
>work of fighting gravity and it's engines only push it along. It's subsonic
>and operates at no more than 40,000 feet altitude. A spacecraft burns the
>same amount of fuel in 4 or 5 minutes fighting gravity and air resistance
>to get to 8 km/sec and 200 km altitude. The stresses on engines and
>airframe are considerably different.
>
I think a better comparison is the SR-71.
It gets to australia and back at some fairly cheap price, without
major mental problems. Or the X-15. it had a fairly substantial
cruise range and was defined as a space craft. Does anyone have
any figures on the costs of either the SR-71/hour or the X-15?
Both of these craft have a much more rigorous operational envelope
yet provided reasonably good flight windows. I'd bet the
X-15 qualified more astronauts in one year then the STS.
>>Getting to space should cost no more than a small multiple of the cost
>>of getting to Australia.
>
>And pigs would fly if they only had wings.
>
All comments aside, I would expect the DC-1 to not cost more then a
small multiple of either the SR-71 or X-15. and to start have
a operational record very similiar to either.
The X-15 had 3? aircraft built to acquire data and flight characterestics,
and aside from some program difficulties. Wrecking one bird, killing
an astronaut??? and bending some metal, plus burning some incredible
holes in places you'd never expect.
I would imagine the X-15 test program should provide a
guide to the difficulties of the DC test program.
I'd be happier if they built 2-3 DC-X test articles, but henry
says they are for real small scale testing. the Y vehicle will
do the serious test program, and that has 3? test vehicles planned.
In Fact, one of the interested areas for the DC-X is as a
fast package express. Anyone think a SR-71 would be
cost effective for this?
pat
------------------------------
Date: Fri, 12 Feb 1993 15:00:26 GMT
From: "Bruce T. Harvey" <idsssd!bruce>
Subject: Homework (was Re: 1st lady Yank)
Newsgroups: sci.space
in article <1993Feb11.182013.1@fnalf.fnal.gov>, higgins@fnalf.fnal.gov (Bill
Higgins-- Beam Jockey) says:
> Message-ID: <1993Feb11.182013.1@fnalf.fnal.gov>
> References: <C28MpK.GnG@compsci.liverpool.ac.uk>
> NNTP-Posting-Host: fnalf.fnal.gov
>
> In article <C28MpK.GnG@compsci.liverpool.ac.uk>, scst83@csc.liv.ac.uk (Mr.
> C.D. Smith) writes:
>> I don't know if it's just the reference books I have got access to, but I
>> cannot find any reference of the 'First American Woman to Walk In Space.' ..
>> Could someone tell me please, as its for a university entrance research quiz
>> and hence REALLY important to me !!!
>
> As you probably know, Usenet is NOT a place to get your homework done for
> you! But I think Usenet is a good place to ask when your library fails you--
> it works for me now and then.
(... the rest of the answer deleted ...)
Well, I can't differ with Usenet not being a place to get your homework done
FOR you, but I (and many of us I daresay) do consider Usenet a 'reference'
encyclopedia of sorts, among other things, which to me appears to be the way
that Mr. Smith was using it. In fact, it's one of the best knowledge-based
systems (organic nodes) I've seen.
Perhaps I'm just a little sensitive to expressions of the way things
'should' be used (or simply sensitive to the 'should' concept altogether),
but Usenet can be many things to many people, even _with_ a mission
statement for a particular newsgroup. Once you provide access to the
general public, the general public makes its desires known.
The index, however, leaves much to be desired. (insert 'smiley' here)
--
::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
Bruce T. Harvey {B-}) ::: UUCP: ... {uunet|mimsy}!wb3ffv!idsssd!bruce
MGR-Applications Dvlpmt::: INTERNET: wb3ffv!idsssd!bruce%uunet.uu.net@...
INSIGHT Dist. Sys. - AD:::CompuServe: 71033,1070
(410)329-1100 x312,x352::: SnailMail: 222 Schilling Cir.,Hunt Valley, MD 21031
::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
------------------------------
Date: 12 Feb 93 17:17:05 GMT
From: Pat <prb@access.digex.com>
Subject: HST repair mission
Newsgroups: sci.space
In article <1993Feb10.071107.28325@news.mentorg.com> drickel@bounce.mentorg.com (Dave Rickel) writes:
>
>the old optics grind their teeth. It'd be nice if NASA would think about
>Hubble Jr., but that's probably a non-starter.
Given that NASA owns a spare mirror, hwo much would it cost
to build a lite telescope, using the mirror, and just a Faint
object camera and maybe a spare WFPC?
I think these were the items that really needed the big mirror.
Certainly, we don't need another 5 billion dollar project, but
how much could be done for 500 million?
ALl the engineerings been done for a large telescope, how hard
would it be to make a stripped follow-up????
pat
------------------------------
Date: Fri, 12 Feb 1993 16:01:06 GMT
From: Dennis Newkirk <dennisn@ecs.comm.mot.com>
Subject: ideas on reviving the SSF project as well as Mir
Newsgroups: sci.space
In article <C2BD3x.CLp@news.cso.uiuc.edu> sas52992@uxa.cso.uiuc.edu (Sanjay Ashok Sheth) writes:
>It has been suggested recently that Space Station Freedom is in serious
>danger of being cut out of the US budget or at least having substantially
>fewer funds made available to it. I have also noted recently in the news
>that the Russian Space Agency is also running out of money and is seriously
>undermanned.
The Russian military space budget has been reduced a lot over the last few
years, but the civilian programs like Mir are functioning almost normally.
>Why not use Mir as a core
>for a new space station that would be built around it? This way, we could
>have maybe half the job done already - the critical components of the space
>station are already up there.
Mir was launched in 1986 and is reaching its design lifetime limits. Many
components will need servicing and replacement to extend its life a few more
years. The Russians could use NASA shuttle support for some of these tasks.
They hope to be able to extend Mir's operation until Mir 2 is launched around
1996. Mir 2 is now designed to be similar to Mir but the modules will be
docked differently (along the core axis not perpendicular) and the core
will be attached to a long truss just like Freedom's with arrays and
radiators mounted away from the core modules.
>The existing funds could then be used to make new modules that could be
>fitted onto Mir like an research module, a industrial module and maybe even
>a recreational module.
An industrial prototype production module is attached to Mir now called
Kristall. 2 other utility modues are also docked. 2 more modules are
awaiting launch in Russia now. Since their lifetime is several years
the Russians do not want to send them to Mir if Mir 2 will be launched
a few years later. Moving the modules between stations would be impossible
for them without a shuttle, and then it would be risky. Mir is not
designed for intensive on orbit construction tasks. The current modules
have no grapple fixtures, etc.. and have little propellant to rendezvous with
Mir 2 and dock again even if their systems were still operable and usefull.
>Russia also has the rockets needed to boost all these components into space
>since they have been resupplying their space stations for years now. Using
>American technology and Russian man-power/components/equipment, the space
>station could be built within 4-5 years instead of waiting many more with
>the danger of being cut each year.
In the 1970's there was an effort made to plan follow-on missions
after ASTP. These included adding Spacelab modules to a Soviet station. It
can be done, and the NASA shuttle is a perfect vehicle to support station
operations. While exploiting Mir now for research is fine, Freedom needs
to be reoriented to a joint program with Russia's Mir 2. Mir is too old
and limited in design to provide any useful function for a future station
to be launched in several years.
Dennis Newkirk (dennisn@ecs.comm.mot.com)
Motorola, Land Mobile Products Sector
Schaumburg, IL
------------------------------
Date: 14 Feb 93 06:09:00 GMT
From: Russell Mcmahon <Russell_Mcmahon@kcbbs.gen.nz>
Subject: kerosene/peroxide SSTO
Newsgroups: sci.space
1. Peroxide decomposition is strongly exothermic.
2 H2O2 --> 2H2O + O2
result is Oxygen and steam.
2. I have been following this thread but did not see the very start.
I am surprised that it is suggested that Peroxide can be used in a SSTO.
Peroxide / Kerosine will generally give a somewhat lower Isp than LOX
/ Kerosene. For the latter Isp is around 280 to 320 depending on chamber
pressure and altitude. The Atlas which was a 1.5 stage used this and
requires very light weight construction. (Empty weight is 5% of full
--> ie mass ratio is 20 which is impressive even now.
A peroxide SSTO would have a lower Isp and 0.5 less stages so if you
could SSTO it it would have a very very low payload as a % of launch
mass.
If people think it can be done please advise how.
(I'll take 10)
------------------------------
Date: Sat, 13 Feb 1993 15:14:28 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Other shuttles (was Re: Getting people into Space Program!)
Newsgroups: sci.space
In article <1993Feb11.221204.27897@iti.org> aws@iti.org (Allen W. Sherzer) writes:
>In article <1993Feb10.173712.4469@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes:
>
>>With spam-in-can you discard 90% of the vehicle on the way up, including
>>avionics and the expensive engines with their precision pumps....
>
>Again, you put the cart before the horse. Doing it the 'primitive' way
>costs far less. If YOU where paying the bills, you wouldn't use Shuttle.
Oh yes, circle the wagons Allen, the railroad is coming to town. The
prime reason for Shuttle *and* SSTO is to cut into that 90% of throwaway.
Just because our first cut at designing a shuttle didn't turn out to be
cheap doesn't mean the idea of reuse isn't sound.
>>but ex-Soviet pricing is suspect. The hypothetical SSTO promises reduced
>>costs *if* the payload can be sent up in <10,000 pound chunks and assembled
>
>Dpeends on your hypotheticals. The Lockheed SSTO lifts 40K+ to LEO.
It does? That's great, same as Shuttle. How long has it been flying?
What's a pound cost to orbit? How many payloads has it booked?
Seriously, from what I've read a big SSTO is easier to design than
a small one. When Lockheed is willing to put a hard design on the
table and guarrantee delivery, this might be the replacement we
need for the aging Shuttle fleet. We've got to have *something*
in about 10 more years.
Gary
--
Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary
Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary
534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary
Lawrenceville, GA 30244 | |
------------------------------
Date: Fri, 12 Feb 1993 22:58:42 GMT
From: Rich Kolker <rkolker@sccsi.com>
Subject: Question Help !
Newsgroups: sci.space
I can't believe there has been so much trouble on this.
The first American wonman to walk in space was Kathy Sullivan. The
first woman to walk in space was Svetlana Savitskaya.
++rich
-------------------------------------------------------------------
rich kolker rkolker@nuchat.sccsi.com
< Do Not Write In This Space>
--------------------------------------------------------------------
------------------------------
Date: 07 Feb 93 17:44:04 GMT
From: Ralph Buttigieg <ralph.buttigieg@f635.n713.z3.fido.zeta.org.au>
Subject: Russian Space Mirror
Newsgroups: sci.space
Has anyone thought about the problems of a Space Mirror system? To light up
large areas of land would require huge mirrors in geostationary orbit. Even
their incidential light could do great damage to astronomy. Also changing
the normal day/night cycle could affect the normal plant and animal life.
However is a more modest scheme may be more practical. If a series of
smallish (100-200 meters) mirrors could be placed in low to medium orbits
you should be able to provide emergency night light to disaster areas. Even
if they were only as bright as 10-20 full moons they would be very usefull
for people coping with floods, bushfires earthquakes etc.
I assume the light could be reflected away from Earth when not required.
What would be a good orbit for such a system? Would two 6 or 12 hour orbits
inclined at 45% to the equator work?
ta
Ralph
--- Maximus 2.01wb
* Origin: Vulcan's World-Sydney Australia 02 635-1204 (3:713/635)
------------------------------
Date: 12 Feb 1993 22:12:29 -0500
From: Pat <prb@access.digex.com>
Subject: Sabatier Reactors.
Newsgroups: sci.space
In article <C29Dyt.1My@zoo.toronto.edu| henry@zoo.toronto.edu (Henry Spencer) writes:
|In article <1l6gmkINNd32@access.digex.com> prb@access.digex.com (Pat) writes:
|>So why was centaur banned? couldn't they have made a few changes to
|>make it "Shuttle-safe"
|
|Difficult, I'm afraid. The problem was a combination of really large amounts
|of cryogenic fuels, pressure-stiffened "balloon" tanks, and an overall load
|that was uncomfortably high and required the ability to dump propellants
|before an emergency landing (two orbiters were modified for that). Plus, in
|my opinion, a certain amount of superstition; in particular, NASA has never
|liked balloon tanks.
|
SO what are Balloon tanks? and how are they different from conventional
tanks? Also, Could shuttle have carried a empty centaur to orbit,
and met up with an orbiting fuel dump? EVA teh astronauts, and have them
gas up the centaur for burn?
THis wouldn't be as cheap, but it would let heavier payloads
go up. I know transferring fuel is a little bit of a problem,
but can it be managed?
|The last straw was that Galileo was the only mission that really had to have
|Centaur. So when "safety" suddenly acquired very high priority, that offered
|the perfect excuse to cancel something the shuttle people had never liked
|much.
|
|You could build a "shuttle-safe" LH2/LOX upper stage, but I think you'd
|have to make it a bit smaller and avoid balloon tanks.
|--
Granted only galileo to date needed the centaur, but other medium weight
missions could certainly use a centaur. ANy outer planets orbiter
or mercury orbiter could certainly use a high performance upper stage.
Gary and Dennis keep raving about how much work you can do with the shuttle
and what a great platform it is for repairs. How about a mission
that actually takes advantage of these features?
Or would it just be better to launch the mission on a Proton or Titan 4
or even energiya?
pat
------------------------------
Date: Fri, 12 Feb 1993 11:02:04 GMT
From: "Hugh D.R. Evans (ESA/ESTEC/WMA Netherlands" <hevans@estwm0.wm.estec.esa.nl>
Subject: Spaceships made of ice: some lighthearted speculation
Newsgroups: sci.space,sci.materials
In article <C2ABB1.J8r@brunel.ac.uk>, mt90dac@brunel.ac.uk (Del Cotter) writes:
|>From: mt90dac@brunel.ac.uk (Del Cotter)
|>Subject: Spaceships made of ice: some lighthearted speculation
|>Date: 11 Feb 93 12:42:33 GMT
|>Organization: Brunel University, West London, UK
|>
|><stephens.729190402@gdim> stephens@geod.emr.ca (Dave Stephenson) writes:
|>>One day reinforced ice ships will cruise the depths of interplanetary
|>>space.
|>
|>The reinforcement will probably not be wood. Has anybody got any ideas for
|>reinforcement using space-based materials?
|>
|>Eg.
|> Pulverised rock from inner moons/asteroids
|> (extremely crude, but surprisingly effective)
|>
|> Polymers from organic precursors on outer moons/comets
|>
|> Wood (well, if you can build big enough greenhouses, why not?)
|>
|>Possible applications?
An intelligent bit of gentic engineering should be able to produce an algae
that can grow in ice with a fiberous structure. This would create a ship
that repairs itself: damage occurs, ice reforms, algae reimpregnates the
ice to provide tensile strength.
In an ideal world, the algae would also be edible.
The real trick would be to train the algae to pre stress the ice for extra
strenth.
Regards,
Hugh Evans
Internet hevans@estwm0.wm.estec.esa.nl
SPAN ESTWM8::hevans
I'm a cat person, myself, she said, vaguely.
A low-level voice said: Yeah? Yeah? Wash in your own spit, do you?
(Terry Pratchett, Moving Pictures)
------------------------------
Date: Sat, 13 Feb 1993 06:26:33 GMT
From: Henry Spencer <henry@zoo.toronto.edu>
Subject: Spaceships made of ice: some lighthearted speculation
Newsgroups: sci.space,sci.materials
In article <flc.729555583@obiwan2> flc@mips.com (Fred Cox) writes:
>The errors seem to be in your memory, not the late Dr. Asimov's story.
>The ice chunk was snagged from Saturn's rings, not from the asteroid
>belt. He specified it as about 2 miles long, not .5 km.
Actually, the one serious error was something Asimov couldn't have
anticipated: the chunks of ice in Saturn's rings are nowhere near
that big. The rings are only maybe 100m thick. (Which is more than
slightly impressive when you consider that they're 275000km across.)
The biggest lumps in them are perhaps tens of meters in diameter.
--
C++ is the best example of second-system| Henry Spencer @ U of Toronto Zoology
effect since OS/360. | henry@zoo.toronto.edu utzoo!henry
------------------------------
Date: 12 Feb 93 16:47:42 GMT
From: Pat <prb@access.digex.com>
Subject: space station cut, goldin to stay on at NASA
Newsgroups: talk.politics.space,sci.space
Todays washington post reported that "NASA Director Goldin in a move
that looks to save his job" has promised that NASA can deliver
a space station for 40% less then current estimates".
Goldin says eliminating "the controversial truss structure"
in favor of a "wo/man in a can" format will provide faster
cheaper access.
the article also quoted "Morale had been very bad at the centers
and contractors" due to proposed cuts and overruns to date,
including a most recent 500 million dollar over-run.
So, if Freedom tosses the truss, how different does it become
from MIR?
------------------------------
Date: 12 Feb 1993 15:11:21 -0500
From: Pat <prb@access.digex.com>
Subject: SSTO news
Newsgroups: sci.space,talk.politics.space
In article <STEINLY.93Feb11123010@topaz.ucsc.edu> steinly@topaz.ucsc.edu (Steinn Sigurdsson) writes:
|
|
|
|Isn't this back to front? After all MD could build their own
|test stands!
|Should we now count the entire construction and operation cost
|of NASA static test stands against DC development, or just the
|marginal cost? ;-)
|
|
|
|
|
THat's silly. only guys with a political agenda use marginal costing.
for real analysis, you want to add the depriciated basis cost for the
time period, plus the time rated unit operation cost, plus any variable
operating cost. Given that most of NASA's test stands are dated
from apollo, i don't think there is much of a depriciation, but
let's say they run for two months of static testing, one could bill
2 months of costs for the center times the percentage size of the stand
to teh center. plus any cost of consumables.
I'd assume NASA maintains the center for testing a number of rocket proto
types.
------------------------------
Date: 12 Feb 93 19:20:51 GMT
From: Bruce Watson <wats@scicom.AlphaCDC.COM>
Subject: Women in EVA (was Re: Question Help !)
Newsgroups: sci.space
In article <1993Feb11.173254.1@stsci.edu| gawne@stsci.edu writes:
|In article <1993Feb11.170254.1259@mksol.dseg.ti.com|,
|mccall@mksol.dseg.ti.com (fred j mccall 575-3539) asks:
|
|| Has there been a female space-walker?
|
|Seems I recall seeing Kathy Sullivan suited up on some mission or other.
|Can't recall the specific mission.
|
|-Bill Gawne, Space Telescope Science Institute
You are correct, Sir.
|
| "Forgive him, he is a barbarian, who thinks the customs of his tribe
| are the laws of the universe." - G. J. Caesar
--
Bruce Watson (wats@scicom.alphaCDC.COM) Bulletin 629-49 Item 6700 Extract 75,131
------------------------------
End of Space Digest Volume 16 : Issue 180
------------------------------