Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V16_3/V16NO363.TXT

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Date: Thu, 25 Mar 93 05:25:58
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #363
To: Space Digest Readers
Precedence: bulk


Space Digest                Thu, 25 Mar 93       Volume 16 : Issue 363

Today's Topics:
             Alumnium was available in Elizabethan times?
                          Artificial Gravity
                                 DC-X
             Flight time comparison: Voyager vs. Gallileo
                          How to cool Venus
                               Mach 25
                            NASA Paperwork
                     Need Mir Mirror Information
                     Pioneer Venus Last Findings
            STS-55 (Columbia) abort (was Aurora?) (3 msgs)
                    STS-55 launch aborted (2 msgs)
                       Time Machine!? (2 msgs)
                            Without a Plan

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

Date: 24 Mar 93 22:17:43 GMT
From: [e-mail]
Subject: Alumnium was available in Elizabethan times?
Newsgroups: sci.space,sci.materials

In article <[e-mail]> [e-mail] (David M. Palmer) writes:
>[e-mail] (The Master) writes:
>>Funny how at the time it would have cost an enormous amount of money
>>and now it's so cheap.  It's almost like thinking of people drinking
>>out of gold Coke cans in the future :)
>
>Gold isn't very useful for Coke cans (not strong enough), but diamond
>will be used for all sorts of things, once nanotech comes in.
                                            ^^^^^^^^

Has anyone ever defined this term?  I seem to be hearing it an awful lot
lately.  (By the way, am I right in thinking that this came from Maxis'
"SimEarth" game?)

+--------------------------------------------------------------------------+
| Ben Lagow                  |    WecomeintotheworldandtakeourchancesFa    |
| Grad Res Asst, MatSE       |    teisjusttheweightofcircumstancesThat'    |
| U. of Illinois, Urbana     |    sthewaythatLadyLuckdancesRollthebones    |
+--------------------------------------------------------------------------+

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

Date: Wed, 24 Mar 1993 17:56:47 GMT
From: Thomas Clarke <[e-mail]>
Subject: Artificial Gravity
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (neil storey)
writes:
>
> Since the film "2001" every school-boy has known that the
> solution to the problem is simple (at least in principle). One
> simply constructs a space station in the form of a torus
> and then spins it at an appropriate rate such that
> the centrifugal force (caused by the centripetal acceleration)
> is equivalent to the force of gravity on earth.

Schoolboys in the fifties (even before Sputnik) knew this also
from the articles and books put out by VonBraun, Ley and others.

In article <[e-mail]> Shannon Thornburg
<[e-mail]> writes:
> In article <[e-mail]> neil storey, [e-mail]
> writes:
>
>   < Some valid discussion and calculations relating to
>     artificial gravity spacecraft deleted >
>
> >...and I believe that a
> >rotation rate of the order of 2 minutes per revolution is the
> >maximum thought to be allowable to prevent the astronauts from
> >being aware of their own rotation.
> >If one accepts this rate of rotation it transpires that to
> >achieve full earth gravity a space-station would need a radius
> >of nearly 4km.
>
> Very close.  Actually, a rotation of rate of 2 to 3 revolutions per
> minute is considered to be acceptable.  At 2 rpm, a radius of 224 meters
> gives one Earth gravity.  An 84 m radius gives one Martian g, which might
> be the ideal for a manned Mars mission.
..
> Many people have pointed out the
> impracticability of attempting to build such a large torus in
> space when every piece must be shuttled from earth.

Nah, its easy:-)  Just connect a bunch of external tanks into a
hexagonal or octagonal ring.  A circular (gravitationally flat)
floor can be laid inside the tanks.  I always thought it
was a waster to throw all that high-energy aluminum in the ET
into the ocean :-(

--
Thomas Clarke
Institute for Simulation and Training, University of Central FL
12424 Research Parkway, Suite 300, Orlando, FL 32826
[phone], FAX: [phone], [e-mail]

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

Date: Wed, 24 Mar 1993 16:07:03 GMT
From: fred j mccall 575-3539 <[e-mail]>
Subject: DC-X
Newsgroups: sci.space

In <[e-mail]> John R. Manuel <[e-mail]> writes:

>In article I write:

>>Are there any articles in Aviation Week, or somewhere similar, about DC-X
>>that someone can refer me to? I'm curious to see the design of the thing
>>and in particular, how it will manage re-entry and still be re-usable.

>I've got a bit more information about DC-X (thanks everyone for the
>pointers), but I still have my question about re-entry: how is DC-Y*
>going to be able to re-enter the atmosphere without experiencing engine
>damage? If it assumes an Apollo-like attitude on re-entry, I'd think that
>there would be a lot of ablative damage to the engines. What do the
>designers plan to do to prevent such damage and still make DC-Y
>immediately reuseable?

Hmmm, I thought it was intended to enter nose first and then do a sort
of 'tip-up loop' to get the engines under it once it was at lower
altitude.  However, if it was decided to reenter tail first, from what
I understand the engines can be run to form a gas layer around the
base that prevents this sort of engine damage -- sounds tricky to me,
though.

--
"Insisting on perfect safety is for people who don't have the balls to live
 in the real world."   -- Mary Shafer, NASA Ames Dryden
------------------------------------------------------------------------------
[e-mail] - I don't speak for others and they don't speak for me.

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

Date: Wed, 24 Mar 1993 15:50:54 GMT
From: Eric H Seale <[e-mail]>
Subject: Flight time comparison: Voyager vs. Gallileo
Newsgroups: sci.space

[e-mail] (Ron Baalke) writes:
>... An 11 year
>drought of new launches ensued from 1978 to 1989 because of this lack
>of foresight in having an established launch vehicle available as a backup.

A dearth of funding for planetary science didn't help much either.  As I
recall, Reagan's "Science Advisor" recommended cancelling ALL funding
for space science missions in the 80's since it was of no immediate
millitary or commercial value (lucky we got anything funded).  Of
course, there weren't any "new start"s in the late 70's either...


My $0.02,
Eric Seale

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

Date: 24 Mar 93 20:52:19 GMT
From: Paul Dietz <[e-mail]>
Subject: How to cool Venus
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Gary Coffman) writes:

 > I think you're wrong about this, in practice if not in principle.
 > And I'd point to the same Soviet test as a counter argument. It's
 > been reported that the Soviet test was intended to be a 100 MT
 > device, but that their hydrocodes weren't advanced enough to
 > allow them to make a bomb that big that wouldn't disassemble
 > itself prematurely.

And what *I've* heard is that they did not wrap a U-238 blanket around
that device (which would have boosted the yield to 100 MT), perhaps
because they didn't want that much fallout.  Dissassembly is
less of a problem in larger devices, since the time it takes
to dissassemble increases with device size.


  > Of course a star is a perfect counterexample
  > as well. Fusion only occurs in the core areas where both compression
  > and temperature are extremely high. Trying for an intermediate
  > yield, between the Soviet bomb and the Sun, presents formidable
  > technical challenges.

Actually, the history of the development of thermonuclear weapons
is that big ones were developed first.  The first one, a bulky
device using liquid deuterium/tritium, achieved 10 MT;  the first
"dry" bomb with Li6-D achieved 15 MT.  Only later were the devices
made smaller, prompted in part by the need for smaller reentry
vehicles for increasingly accurate MIRVed missiles.

The compression bit is simply false.  The analogy to a star is bogus,
as a star is burning ordinary hydrogen, a far inferior fuel.  A big
enough thermonuclear bomb need use no compression at all.  It's not
hard to see why.

The rate at which a given mass of fuel is consumed in a plasma of a
given composition at a given temperature is proportional to its
density (clearly, since doubling the density doubles the rate at which
a given nucleus collides with other nuclei).  The density does not
serve to overcome the coulomb barrier between nuclei; kinetic energy
(heat) does that.  For example, even in highly compressed (1000x) DT
targets for laser fusion, nuclei are still > .1 angstroms apart, on
average.

The time required for a (nondegenerate) plasma of a given temperature
to blow apart is proportional to its linear dimensions, say r.
The time required to consume half the fuel is proportional to the
density rho.   Now, since mass is proportional to r^3 rho, we get
that the minimum mass required to fuse a specified fraction
of the nuclei before disassembly scales as rho^-2.

Laser fusion targets are to achieve yields of about 1 ton of TNT, with
about .01 tons of driver energy, with core densities around 1000x
normal.  Therefore, yields of about 1 MT with a 10 kT driver would
naively require no compression (in practice, driving with a bomb is
different from driving with lasers, so some compression is required
here).  But clearly going to still larger bombs gives more slack, as
the fuel density stays constant.  And we know we can build > 10 MT
drivers, so there's three orders of magnitude of slack to play with.

(SF story idea: nuclear terrorists steal a multi-MT bomb and
hijack the Sudbury Neutrino Observatory, threatening to detonate
its 1000 tons of heavy water which, if fully fused, makes a ~10 GT
blast and ejects cubic kilometers of rock vapor into the atmosphere.)

  >> Antimatter would not be sensible, as it would be much too expensive
  >> to make.
  >
  > Today. It will continue to be expensive in energy required, but if
  > the price of energy is sufficiently low, it might become economical.
  > There are few technical reasons why an anti-matter explosive can't
  > be any arbitrary size.

Assuming we can make antimatter at .1% efficiency (probably close to
the theoretical limit, and much much better than is done today), I
compute that for equal sized bombs, electricity costs for antimatter
production exceed deuterium separation costs for thermonuclear
explosives by about six orders of magnitude (using $.05/kWh for
electricity and $2M/ton for deuterium).  Is the relative cost really
going to change by this much?  I doubt it.

    Paul

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

Date: 24 Mar 93 21:14:27 GMT
From: David Geiser <[e-mail]>
Subject: Mach 25
Newsgroups: sci.space

Oxymoron:  Popular Science
--
To know recursion, you must first know recursion.
--

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

Date: Wed, 24 Mar 1993 16:36:24 GMT
From: fred j mccall 575-3539 <[e-mail]>
Subject: NASA Paperwork
Newsgroups: sci.space

In <[e-mail]> [e-mail] ("F.Baube[tm]") writes:

>This message might be WAY off base, but ..

>Okay, so there's lots of paperwork, and reasons for it.

>But lately it seems like when something on a spacecraft is stuck,
>a mechanical problem, it was caused by a mallet whack, or the use
>of the wrong fastener, or something similarly trivial.  Trivial
>until a multi-zillion-dollar vehicle has a mechanical failure.

>Let's say it was a whack with a mallet to get something to fit.
>After the deployment problem, this mallet whack is traced.

>Was this mallet whack noted in the paperwork ?

>If so .. Who signed off on it ?  Wasn't there a procedure to
>require an assessment of the possible effect of a mallet whack ?
>Or did some assembly tech just do it and not have to tell anyone ?

>If the mallet whack wasn't in the paperwork .. Why not ?

>In either case, what then is the point of all the paperwork,
>if it can't stop simple mechanical problems caused during
>spacecraft assembly ?

See my .sig.  No matter how much cost and paperwork you add to the
cycle to try to get there, you simply ain't going to make it.  In
fact, at some point you become counter-productive as the extra effort
to achieve absolute perfection becomes another source for errors.

You pays your money and you takes your chances.

--
"Insisting on perfect safety is for people who don't have the balls to live
 in the real world."   -- Mary Shafer, NASA Ames Dryden
------------------------------------------------------------------------------
[e-mail] - I don't speak for others and they don't speak for me.

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

Date: 24 Mar 93 21:27:33 GMT
From: Stephen Musko <[e-mail]>
Subject: Need Mir Mirror Information
Newsgroups: sci.space

Recently a large mirror was deployed from the Mir space station.  I'd
appreciate any information such as:
- Mirror size and pointing accuracy
- Mirror materials
- And especially: the name and email addr of the Russian principle
investigator
We are proposing a wind measuring satellite that uses a solar pumped laser
and would be most interested in talking with the Russian group responsible
for the Mir mirror. Please reply here or to
[e-mail].
Thanks in advance,
Steve Musko
University of Michigan Space Physics Research Laboratory

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

Date: 24 Mar 93 20:54:27 GMT
From: Ron Baalke <[e-mail]>
Subject: Pioneer Venus Last Findings
Newsgroups: sci.space,sci.astro,alt.sci.planetary

Paula Cleggett-Haleim
Headquarters, Washington, D.C.                             March 24, 1993
(Phone:  [phone])

Peter Waller
Ames Research Center, Mountain View, Calif.
(Phone:  [phone])

RELEASE:  93-51

EVIDENCE POINTS TO OCEANS, LIGHTNING ON EARLY VENUS

    The last findings by the Pioneer Venus Orbiter spacecraft have provided
strong new evidence that planet Venus once had three and a half times more
water as thought earlier -- enough water to cover the entire surface between 25
and 75 feet deep (762 and 2286 centimeters).

    These findings also give new support for the presence of lightning on
Venus and discoveries about the ionosphere and top of the atmosphere of
Venus.  Considered Earth's twin planet, Venus today is very dry and searing hot.

    Pioneer entered Venus' atmosphere on Oct. 8, 1992, and burned up soon
after, ending 14 years of exploration.

    "Many of us have long thought that early in its history Venus had
temperate conditions and oceans like Earth's," said Dr. Thomas Donahue,
University of Michigan, head of the Pioneer Venus science steering group.

    "Findings that Venus was once fairly wet does not prove that major
oceans existed, but make their existence far more likely," he said.  "The new
Pioneer data provides evidence that large amounts of water were definitely
there," said Donahue.

    "Most scientists think Venus' early oceans vaporized and 'blew off' 3
billion years ago in a runaway greenhouse effect when the cool early sun
increased its luminosity and heated the planet very hot," he said.  "The oceans
evaporated.  Solar ultraviolet radiation split the water molecules into
hydrogen and oxygen, and the hydrogen was lost to space.

    "Pioneer Venus Probe and Orbiter data showed early in the mission,"
Donahue said, "that on Venus heavy habundant relative to ordinary hydrogen
than on Earth and everywhere else we've looked in the solar system -- Mars,
Comet Halley, meteorites, Jupiter and Saturn."  Venus' remarkable
hydrogen/deuterium ratio has since been confirmed by independent measurements.

    Abundant deuterium is taken as clear evidence that Venus once had 150
times as much water in its atmosphere as today, he said.  This is because the
water's ordinary hydrogen has escaped.  But most of the water's heavy hydrogen
(deuterium - twice as heavy as hydrogen) stayed behind because of its weight.

    When the Orbiter made its final descent to unexplored regions only 80
miles (129 kilometers) above Venus' surface, it found evidence for 3.5 times as
much water as previously suggested by the deuterium ratio.

    "We found a new and important easy-escape mechanism, which
accelerates hydrogen and deuterium away from the planet," he said.  "This
means that much more hydrogen had to escape to build up the present high
deuterium concentration.  A lot more hydrogen lost means a lot more water
early on," he said.  "This also rules out theories of a dry-from-the-beginning
Venus, whose present meager supply of water comes from an occasional comet
impact."

    The data also show that at Pioneer's lowest altitude 80 miles (129
kilometers) "whistler" radio signals, believed generated by Venus' lightning,
were the strongest ever detected.  Pioneer has long measured such "lightning"
signals.  They are the same as the radio signals used in most lightning studies
on Earth.

    In its final orbits, Pioneer penetrated 7 miles (11 kilometers) below
the peak of Venus' ionosphere, which tends to block these radio signals.
Here also, the magnetic fields which channel the signals were the strongest
ever seen on Venus' night side.

    "These results are best explained by a strong and persistent source of
lightning in the Venus atmosphere," said Robert Strangeway of UCLA, Pioneer
electric field investigator.

     Some scientists continue to doubt Venus lightning.  They say only
optical sightings can prove lightning.  A Russian spacecraft has reported
visible-light sightings of lightning.  Four Russian spacecraft and the U.S.
Galileo craft also have observed radio signals believed from lightning.

    Pioneer found the peak density of Venus' ionosphere for the first
time - at 87 miles (139 kilometers).  The ionosphere was much different
between solar maximum and minimum, which are high and low periods of storm
activity on the sun and in the solar wind.  At minimum, it was far smaller.
It was gone altogether above 85 miles (136 kilometers), and its lower layer
was half as dense.  It was more variable, much cooler, and full of small
structures (1-60 miles in size (1.6-96 kilometers).

    For the ionosphere on the night side, at solar minimum, hydrogen ions
were reduced 20 times.  Its lower layer was half as dense as at maximum.

    Over 3 months, Pioneer provided data from 80 to 210 miles (129 to 336
kilometers) altitude.  It found the beginning of Venus' real, mixed atmosphere
(transition from oxygen to carbon dioxide) at 80 miles (129 kilometers).  Below
85 miles (136 kilometers), it identified various waves and a 4-day oscillation
of Venus' atmosphere top.  The neutral atmosphere above 185 miles (296
kilometers) was more than 10 times denser and 2120 F (1,000 degrees Celsius)
hotter than thought.

    Working with Donahue were Drs. Richard Hartle and Joseph Grebowsky of
NASA's Goddard Space Flight Center, Greenbelt, Md.  Ames Research Center
manages the Pioneer project for the Office of Space Science, NASA
Headquarters, Washington, D.C.

- end -
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Don't ever take a fence
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | down until you know the
|_____|/  |_|/       |_____|/                     | reason it was put up.

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

Date: Wed, 24 Mar 1993 16:12:39 GMT
From: "Phil G. Fraering" <[e-mail]>
Subject: STS-55 (Columbia) abort (was Aurora?)
Newsgroups: sci.space

[e-mail] (Simon E. Booth) writes:


>In article <[e-mail]> [e-mail] (Dean Adams) writes:
>>
>>[e-mail] (Simon E. Booth) writes:
>> >>When you can tell me who the PRIME CONTRACTOR is for your "ufos",

YoYoDyne Propulsion Systems, a division of YoYoDyne Aerospace.
--
Phil Fraering         |"...drag them, kicking and screaming,
[e-mail]|into the Century of the Fruitbat." - Terry Pratchett,
                       _Reaper Man_

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

Date: 24 Mar 93 20:34:17 GMT
From: "Simon E. Booth" <[e-mail]>
Subject: STS-55 (Columbia) abort (was Aurora?)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] (Simon E. Booth) writes:
>>My friends and I were debating about whether or not Columbia could have
>>reached orbit if the engine failure had occured at T-zero. Once the SRB's
>>ignite, they have no choice but to launch.
>
>No, they can't make orbit with an engine failure at liftoff.  I would
>think they'd have to do an RTLS abort, after SRB burnout; I don't think
>they can even go trans-Atlantic with a failure that early.

I've wondered if using strap-on liquid fueled boosters would solve this
problem-I mean being commited to launch at T-zero even with a main engine
out.  Theoretically, liquid fueled boosters could be shut down after
ignition, if the shutdown could be performed as quickly as the main
engine's was
>
>An operational space transport system *ought* to be able to reach orbit
>with one engine out at liftoff, but the shuttle wasn't designed that way.
>
>>I shudder to think what an RTLS abort would have been like with the extra
>>weight of the Spacelab on board.
>
>RTLS abort is scary at the best of times.  There was a proposal that the
>very first launch should be flown as a practice RTLS abort; John Young's

Supposedly it's been said that an RTLS abort landing would be near
suicidal.  I don't remember where I heard this though.


I've often wondered why there were no test flights before manned flights
started.  At least they should have tried one of the Approach and Landing
Tests with the Enterprise landing on the KSC shuttle runway.
Simon

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

Date: Wed, 24 Mar 1993 16:59:16 GMT
From: Henry Spencer <[e-mail]>
Subject: STS-55 (Columbia) abort (was Aurora?)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Simon E. Booth) writes:
>My friends and I were debating about whether or not Columbia could have
>reached orbit if the engine failure had occured at T-zero. Once the SRB's
>ignite, they have no choice but to launch.

No, they can't make orbit with an engine failure at liftoff.  I would
think they'd have to do an RTLS abort, after SRB burnout; I don't think
they can even go trans-Atlantic with a failure that early.

An operational space transport system *ought* to be able to reach orbit
with one engine out at liftoff, but the shuttle wasn't designed that way.

>I shudder to think what an RTLS abort would have been like with the extra
>weight of the Spacelab on board.

RTLS abort is scary at the best of times.  There was a proposal that the
very first launch should be flown as a practice RTLS abort; John Young's
alleged response was "you don't have to practice bleeding!".
--
All work is one man's work.             | Henry Spencer @ U of Toronto Zoology
                    - Kipling           |  [e-mail]  utzoo!henry

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

Date: 24 Mar 93 20:38:55 GMT
From: "Simon E. Booth" <[e-mail]>
Subject: STS-55 launch aborted
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] (Simon E. Booth) writes:
>>Incidentally, in the technicl info recently posted to this group on the
>>DC spacecraft, it was mentioned that the shuttle program had experience
>>a 'near crash' on landing.  When was this and which orbiter was involved?
>
>The one I was thinking of when I wrote that was when Atlantis landed nearly
>600ft short of the runway at Edwards in April 1991.  Not too bad in itself,
>especially on the lakebed, but distinctly unsettling.  Heads rolled in
>the weather office afterward.

Now I know why landings at KSC didn't occur for a while.  Much less
margin for error than at Edwards...
>
>There are some other cases you can argue about, like the pilot-induced
>oscillation during the landing tests, and Columbia's tire burst at KSC
>(which was decidedly scary because the shuttle landing gear has slim
>margins -- had it happened a bit earlier, the orbiter might have been
If I recall, the tire burst was caused by brakes being overheated.
Wasn't this part of the reason KSC landings were prohibited at one
point?

Were the other orbiter's retrofitted with drag chutes?

(I think they should have been installed all along!! )

Simon

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

Date: Wed, 24 Mar 1993 17:21:32 GMT
From: Henry Spencer <[e-mail]>
Subject: STS-55 launch aborted
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Simon E. Booth) writes:
>Incidentally, in the technicl info recently posted to this group on the
>DC spacecraft, it was mentioned that the shuttle program had experience
>a 'near crash' on landing.  When was this and which orbiter was involved?

The one I was thinking of when I wrote that was when Atlantis landed nearly
600ft short of the runway at Edwards in April 1991.  Not too bad in itself,
especially on the lakebed, but distinctly unsettling.  Heads rolled in
the weather office afterward.

There are some other cases you can argue about, like the pilot-induced
oscillation during the landing tests, and Columbia's tire burst at KSC
(which was decidedly scary because the shuttle landing gear has slim
margins -- had it happened a bit earlier, the orbiter might have been
a writeoff).
--
All work is one man's work.             | Henry Spencer @ U of Toronto Zoology
                    - Kipling           |  [e-mail]  utzoo!henry

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

Date: 24 Mar 93 19:04:40 GMT
From: Dave Jones <[e-mail]>
Subject: Time Machine!?
Newsgroups: sci.space

David Lai ([e-mail]) wrote:
> Hi netters,
>
>     I remember from my youth, I've been thinking of a time machine
> which can go back to the past.  I heard from some other people say that
> scientists are doing researches and that has something to do with, say,
> magnetic fields or magnetic related things.  I'm wondering whether there
> is actually ANY scientists doing research on time machine?  And if so,
> how's the progress?
>
>     This should be an interesting question to discuss.  Give your
> comments!
>

Its all been theory.  There were claims that certain situations, which
weren't necessarily practical to engineer, would result in 'timelike world
lines' which is jargon for going into your own past.  The latest one to
appear suggests that one method, involving wormholes connected together and
move around each other at high speed, would fail because (if memory serves)
the quantum effects resulting from bringing them back together would destroy
the setup, in the same way that black holes are supposed to evaporate over
time.

--
||Reading online docs is like watching |
||football through a hole in a fence   |
||-------------------------------------|
||Dave Jones ([e-mail])|

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

Date: 24 Mar 93 17:12:16 GMT
From: David Lai <[e-mail]>
Subject: Time Machine!?
Newsgroups: sci.space

Hi netters,

    I remember from my youth, I've been thinking of a time machine
which can go back to the past.  I heard from some other people say that
scientists are doing researches and that has something to do with, say,
magnetic fields or magnetic related things.  I'm wondering whether there
is actually ANY scientists doing research on time machine?  And if so,
how's the progress?

    This should be an interesting question to discuss.  Give your
comments!

                    David.

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

Date: Wed, 24 Mar 1993 16:40:03 GMT
From: fred j mccall 575-3539 <[e-mail]>
Subject: Without a Plan
Newsgroups: sci.space,talk.politics.space

In <[e-mail]> [e-mail] (Nick Szabo) writes:

>[e-mail] (Doug Mohney) writes:

>>[Comparing me to Dennis Wingo]
>>You've just got your hand out for money for a lot of politically unrealistic
>>projects.


>This is truly backwards.  Dennis Wingo is a bureaucrat working for
>NASA, and constantly posting with his hand out, begging money for
>obsolete projects costing $100's of billions.

You must be reading an entirely different sci.space newsgroup than the
rest of us are, Nick.

>I volunteer part
>of my time designing space projects that _pay for themselves_ by
>meeting people's needs in the market, while full time working in the
>private sector, producing things people want and need rather than what
>politicians think they want and need.

And what projects have you flown?  I've seen your idea of 'space
projects' -- things like Antarctic meteor hunts.

>All I ask is that NASA
>use its budget more wisely, and devote more of it to projects that
>are important to self-sufficient space development, and be far more
>open-minded about the wide range of future possibilities for such
>development, instead of isolating itself in its own little world of
>pork & glory (aka "vision", aka "The Space Program") and demanding
>that everybody else to goose-step to their drum.

Translation:  Nick wants NASA to spend money on what *he* wants them
to spend it on and demands that NASA goose-step to his drum.

--
"Insisting on perfect safety is for people who don't have the balls to live
 in the real world."   -- Mary Shafer, NASA Ames Dryden
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[e-mail] - I don't speak for others and they don't speak for me.

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End of Space Digest Volume 16 : Issue 363
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