Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V16_4/V16NO430.TXT

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Date: Wed,  7 Apr 93 05:22:45
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #430
To: Space Digest Readers
Precedence: bulk


Space Digest                Wed,  7 Apr 93       Volume 16 : Issue 430

Today's Topics:
                       Abyss: breathing fluids
                         ACM and the Universe
              Blow up space station, easy way to do it.
                       Brazilian space program
                   DC-X: Vehicle Nears Flight Test
             DC-X: Vehicle Nears Flight Test (questions?)
   Hypothetical planet inside of mercury's orbit (was Vulcan....)
                       Info on Probe Computers
                               Mach 25
                     MACH 25 landing site bases?
                        nuclear waste (3 msgs)
               Small Astronaut (was: Budget Astronaut)
                          space food sticks

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

Date: Wed, 7 Apr 93 09:25:36 BST
From: Greg Stewart-Nicholls <[e-mail]>
Subject: Abyss: breathing fluids
Newsgroups: sci.space

In <1psghn$[e-mail]> Pat writes:
>In article <[e-mail]> [e-mail] (Achurist) writes:
>|
>|I believe the reason is that the lung diaphram gets too tired to pump
>|the liquid in and out and simply stops breathing after 2-3 minutes.
>|So if your in the vehicle ready to go they better not put you on
>|hold, or else!! That's about it. Remember a liquid is several more times
>|as dense as a gas by its very nature. ~10 I think, depending on the gas
>|and liquid comparision of course!
>
>Could you use some sort of mechanical chest compression as an aid.
>Sorta like the portable Iron Lung?   Put some sort of flex tubing
>around the 'aquanauts' chest.  Cyclically compress it  and it will
>push enough on the chest wall to support breathing?????
>
>You'd have to trust your breather,  but in space, you have to trust
>your suit anyway.
>
>pat
>
 The only reason you inhale and exhale is to exchange good air for
bad. If you're breathing fluid, you could mechanically circulate the
fluid through the lung-helmet-filter system. Provided you maintain
the oxygen content of the fluid in the lung, you shouldn't need to
inhale/exhale.
 -----------------------------------------------------------------
 .sig files are like strings ... every yo-yo's got one.
Greg Nicholls ... [e-mail] (business) or
                  [e-mail] (private)

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

Date: 6 Apr 93 08:28:35 GMT
From: Charles Lindsey <[e-mail]>
Subject: ACM and the Universe
Newsgroups: sci.space

It seems that ACM are getting all geared up for the Space Age when it
arrives.

I have just signed a release form for the videotaping/audiotaping of a
Conference where I am to present a paper. The rights I have signed away
are amazing, including the use of my image and voice for all sorts of
unspecified and unimaginable purposes.

However, the real surprise was that I was asked to give my rights away
"in perpetuity" (probably reasonable, but I shan't really care then)
and "throughout the Universe".

I did seriously consider writing in that I retained my rights to the
use of these things in Alpha Centauri.


--
Charles H. Lindsey -------------------------------------------------------------
           At Home, doing my own thing.           Internet: [e-mail]
Voice: [phone]                            Janet:    [e-mail]
Snail: 5 Clerewood Ave., CHEADLE, SK8 3JU, U.K.   UUCP:     mucs!clerew!chl

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

Date: 7 Apr 93 05:35:08 GMT
From: Ken Kobayashi <[e-mail]>
Subject: Blow up space station, easy way to do it.
Newsgroups: sci.space

   The concept of inflatable space structures always reminds me of a scene
in Allan Steele's "Orbital Decay" where an inflatable part of the space
station gets hit by a spacecraft and rips apart.  Is this a real concern?
Could inflatable structures be more dangerous than rigid ones?


--
      Ken Kobayashi
[e-mail]        |   "There is no final frontier." - IBM ad

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

Date: 7 Apr 93 01:11:04 GMT
From: Joseph Askew <[e-mail]>
Subject: Brazilian space program
Newsgroups: sci.space

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

I found this is soc.culture.china (what it was doing there I have no idea)
Can anyone comment on its accuracy? I thought the US was leaning on Brazil
not to develop ICBM-type technology. Satellite launchers included.

-----------------------------ENCLOSURE---------------------------------
Subject: Brazil launches first rocket
Date: Fri, 2 Apr 93 10:30:46 PST

        BRASILIA, Brazil (UPI) -- Brazil joined the select group of nations
capable of putting satellites in orbit Friday when it successfully
launched its first locally constructed rocket, government officials
said.
        Brazilian technicians and scientists launched the VS-40 rocked at
7:34 a.m. from the Alcantara air base in Maranhao state, 1,400 miles
northwest of Brasilia, according to the director of the space center
there, Commander Carlos Augusto Ancilon Cavalcante.
        The rocket flew to an altitude of 780 miles and fell 24 minutes later
into the Atlantic Ocean off Natal, Brazil, more than 1,200 mileshwest of
Alcantara, Ancilon Cavalcante said.
        ``It was an absolute success,'' Ancilon Cavalcante told reporters
after President Itamar Franco and 60 otheric watched the launch.
``We have taken an important step toward dominating satellite-launching
technology.''
        Franco, 62, then announced his government had decided to create the
Brazilian Space Agency.
        ``The project will be sent to the National Congress and we will ask
that it is considered urgently,'' Franco said.
        Brazilian scientists included an experiment on the rocket to study
solar ray effects. Ancilon Cavalcante said his team of scientists
expects to be able to build a vehicle to launch satellites within three
years.
        The South American nation thus hopes to save the $130 million needed
to rent launching pads and vehicles at Cape Canaveral, Fla., or Kourou,
French Guyana.
        ``Also, it won't be necessary for the country to wait in line for up
to two years for foreign centers to launch satellites,'' Ancilon
Cavalcante said.
        Ancilon said Alcantara had some of the most favorable conditions for
satellite launching in the world, noting it was two degrees below the
equater, a fact that would allow them to use 30 percent less fuel than
Cape Canaveral or Kourou and save time and money on satellite launches.
        He said the U.S. National Aeronautics and Space Administration plans
to use the Alcantara base between October and December of this year to
launch 12 test rockets and 20 meteorological satellites.
        Ancilon said the Brazilian government was also negotiating with the
world's largest rocket-makers, Lockheed of the United States and
Krunichev of Russia, on renting out Alcantara for launches.
        Brazil currently has two satellites, the Brasil-sat, launched eight
years ago, and an environmental and weather satellite launched in
February from Cape Canaveral.

------------------------END---------------------

Joseph Askew

--
Joseph Askew, Gauche and Proud  In the autumn stillness, see the Pleiades,
[e-mail]  Remote in thorny deserts, fell the grief.
Disclaimer? Sue, see if I care  North of our tents, the sky must end somwhere,
Actually, I rather like Brenda  Beyond the pale, the River murmurs on.

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

Date: 6 Apr 1993 18:33:57 GMT
From: steve hix <[e-mail]>
Subject: DC-X: Vehicle Nears Flight Test
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:
>
>Since the DC-X is to take off horizontal, why not land that way??

Well, since it *doesn't* launch horizontally in the first place...

>Why do the Martian Landing thing..  Or am I missing something.. Don't know to
>much about DC-X and such.. (overly obvious?).

Hmmm.

>Why not just fall to earth like the russian crafts?? Parachute in then...

Single-Stage To Orbit is marginal as it is, why toss out all your payload
capability for landing parachutes?

--
-------------------------------------------------------
| Some things are too important not to give away      |
| to everybody else and have none left for yourself.  |
|------------------------ Dieter the car salesman-----|

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

Date: 7 Apr 93 00:27:23 GMT
From: [e-mail]
Subject: DC-X: Vehicle Nears Flight Test (questions?)
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Josh Hopkins) writes:
> [e-mail] writes:
>
> [Excellent discussion of DC-X landing techniques by Henry deleted]
>
>>Since the DC-X is to take off horizontal, why not land that way??
>
> The DC-X will not take of horizontally.  It takes of vertically.

>
>>Why do the Martian Landing thing..
>
> For several reasons.  Vertical landings don't require miles of runway and limit
> noise pollution.  They don't require wheels or wings.  Just turn on the engines
> and touch down.  Of course, as Henry pointed out, vetical landings aren't quite
> that simple.
>
>>Or am I missing something.. Don't know to
>>much about DC-X and such.. (overly obvious?).
>
> Well, to be blunt, yes.  But at least you're learning.
>
>>Why not just fall to earth like the russian crafts?? Parachute in then...
>
> The Soyuz vehicles use parachutes for the descent and then fire small rockets
> just before they hit the ground.  Parachutes are, however, not especially
> practical if you want to reuse something without much effort.  The landings
> are also not very comfortable.  However, in the words of Georgy Grechko,
> "I prefer to have bruises, not to sink."
>
>
> --
> Josh Hopkins                                          [e-mail]
>           "Tout ce qu'un homme est capable d'imaginer, d'autres hommes
>                      seront capable de la realiser"
>              -Jules Verne


Quyanna for correcting me without insulting me (flames and such).
Okay so the DC-X is to land vertically (reasons explains) maybe use the
Russian Way (parachutes) or something similar.. I know its nice to have powered
flight all the way down, but.. Or maybe a system in ways liek the Osprey (no
not with propellors), but have someform of manuvering jets or ?? (or do I show
my ignorance once again? I am learning.. Need to find a article on DC-X and
read more.. I am at the library..))
Use the parachutes to slow your decent down (from the rear) and then to bring
you around to verical and then loose them (parachutes can be recovered very
easy)..

Other odd question where will the DC-X take off from and land at? Edwards or
??White Sands?? Near Fort IRwin/Goldstone...???
Just being a busy body..

Michael Adams, Ignorant of DC-X so enlighten me..

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

Date: Wed, 07 Apr 1993 01:08:44 GMT
From: nathan wallace <[e-mail]>
Subject: Hypothetical planet inside of mercury's orbit (was Vulcan....)
Newsgroups: sci.space

(Note to those who read my earlier postings and had line overflow: sorry!
I have fixed my parameters and hopefully won't repeat this!)

Could someone take a moment to address the question of how close to
the sun a planet could get before it either burned away in the atmosphere
of the sun or was melted by solar radiation? I presume Mercury is not in
the closest possible orbit, by the way.

Thanx!
---
C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/
C/    Nathan F. Wallace                   C/C/           "Reality Is"         C/
C/    e-mail: [e-mail]   C/C/    ancient Alphaean proverb    C/
C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/C/


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

Date: Tue, 6 Apr 1993 23:19:40 GMT
From: [e-mail]
Subject: Info on Probe Computers
Newsgroups: sci.space,alt.folklore.computers

In article <1phu90$[e-mail]>, [e-mail] (Pat) writes:
>
> Actually this shouldn't be that difficult.
> What ytouare describing is a machine simulator.  I've done it for
> Hardware developement projects, and given the small size of
> probe computers, it should be fairly straight forward.

Ironically it sounds like the later, more complex systems will be easier
to simulate. Apparently the earlier beasts didn't have computers in the
Von Neumann sense, so a lot will depend on how good the documentation is.

> THe hardest part will be developing useful simulations of probe
> sensor data streams.  FOr these you need a small
> universe that's work.  IT depends if you just want to test
> command sequences or fully model the bird.

Yep, that will be the fun bit... Initially I want to concentrate on the
probe internals to try and get a handle on _why_ they used code X for
stage Y of the mission, but eventually I'd like to go to a full-scale sim,
which is going to mean a LOT of reading (me philosopher - no speak physics).

Simon Brady                 I'm OK. You're OK. COBOL programmers are
University of Otago         _not_ OK.
Dunedin, New Zealand

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

Date: Wed, 7 Apr 1993 05:26:58 GMT
From: Henry Spencer <[e-mail]>
Subject: Mach 25
Newsgroups: sci.space

In article <[e-mail]> [e-mail] ("RWTMS2::MUNIZB") writes:
>Have any laser or microwave driven *rockets* ever been tested ...

The problem is that the power requirement scales linearly with exhaust
velocity, for constant thrust.  A helicopter is the best case, very low
exhaust velocity.  For a practical rocket, you want exhaust velocities
of kilometers per second, and you need megawatts per kilogram.  This
means a *big* laser.

Kare's group did ground tests of propulsion hardware but did not quite
get to the point of flying anything.  They have a design for what Jordin
calls "the laser bottle rocket" that could fly a semi-captive test (going
up a pair of wires) with existing laser hardware and not much more effort.
This would verify things like thrust vectoring.  If I recall correctly,
the next step after that was a suborbital demo, again using existing lasers.

>... Should SSI be examining more promising
>approaches other than/in addition to  Myrabo's air-breathing, multiple-cycle
>engines for small, personal launch vehicles?

How did "personal" creep in here?  Let's talk about launch systems, and
leave Myrabo's "family spaceship" for the next generation of hardware.
Yes, SSI most emphatically should be looking at near-term approaches as
well as long-term ones.  Myrabo specializes in elaborate fantasies that
might eventually be feasible; practical laser launch systems could be
built **TODAY** if you're willing to settle for smaller payloads and
more modest performance.
--
All work is one man's work.             | Henry Spencer @ U of Toronto Zoology
                    - Kipling           |  [e-mail]  utzoo!henry

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

Date: 6 Apr 93 17:57:38 -0800
From: [e-mail]
Subject: MACH 25 landing site bases?
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] writes:
> The supersonic booms hear a few months ago over I belive San Fran, heading east
> of what I heard, some new super speed Mach 25 aircraft?? What military based
> int he direction of flight are there that could handle a Mach 25aircraft on its
> landing decent?? Odd question??
>
> ==
> Michael Adams, [e-mail] -- I'm not high, just jacked
>
Even if there was such a thing as a Mach 25 aircraft, they would not land at
supersonic speeds.

Hank - sorry no fancy tag line - M.

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

Date: 6 Apr 93 18:12:00 PST
From: "RWTMS2::MUNIZB" <[e-mail]>
Subject: nuclear waste

on Date: Mon, 5 Apr 1993 13:16:34 GMT, Paul Dietz <[e-mail]>
writes:

/Briefly, there is nothing in oil that cannot be replaced with
/nonfossil fuel sources, at some cost.  Another source of energy
/is needed, but there are several options there.

I remember hearing that: oil is more useful (worth more?) as petrochemical
products such as plastics and fertilizers than as a fuel since there are other
energy sources that can be used, but no other readily available feedstocks; but
oil is still used because of energy density/storability probelms with alternate
sources.


Disclaimer: Opinions stated are solely my own (unless I change my mind).
Ben Muniz     [e-mail]    w(818)586-3578
Space Station Freedom:Rocketdyne/Rockwell:Structural Loads and Dynamics
   "Man will not fly for fifty years": Wilbur to Orville Wright, 1901

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

Date: Tue, 6 Apr 93 20:30:58 GMT
From: Dave Jones <[e-mail]>
Subject: nuclear waste
Newsgroups: sci.space

William Reiken ([e-mail]) wrote:
> In article <[e-mail]>, [e-mail] (Matthew DeLuca) writes:
> >
> > Greedy little oil companies?  Don't blame them; oil companies just supply the
> > demand created by you, me, and just about everyone else on the planet.  If we
> > run out, its all our faults.
> >
>
>     Ok, so how about the creation of oil producing bacteria?  I figure
> that if you can make them to eat it up then you can make them to shit it.
> Any comments?
>

Yes, there's a small matter of energy input going to oil.  That's why it's
an energy source - it contains more energy than its combustion products.  If
you want to reverse that you need energy.  If your starting material is
_more_ energetic then you might want to consider using it directly - the
conversion has to waste energy, though the fact that oil is a fluid and,
say, coal is not might make it worthwhile.  And the inevitable comment that
you should use solar energy to drive this gets the answer: Yes, but it makes
more sense to go with the organisms that have been doing it for millions of
years (aka plants) than to engineer that into bacteria.

--
||Nothing can prepare you for the revelation   ||"You have reached the phone
||that your favorite movie director is a dweeb.|| system of Muzak, Inc.
||---------------------------------------------|| While you wait you will hear
||Dave Jones ([e-mail])--------|| live US Senate proceedings"

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

Date: Wed, 7 Apr 1993 05:29:18 GMT
From: Henry Spencer <[e-mail]>
Subject: nuclear waste
Newsgroups: sci.space

In article <[e-mail]> [e-mail] ("RWTMS2::MUNIZB") writes:
>I remember hearing that: oil is more useful (worth more?) as petrochemical
>products such as plastics and fertilizers than as a fuel since there are other
>energy sources that can be used, but no other readily available feedstocks...

As I recall, at the peak of oil prices, carbonate rock was within a factor
of five of being economically feasible as a chemical feedstock.  (I may
have the number wrong, but the factor wasn't huge.)  There is lots of
carbonate rock.
--
All work is one man's work.             | Henry Spencer @ U of Toronto Zoology
                    - Kipling           |  [e-mail]  utzoo!henry

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

Date: 7 Apr 93 01:47:03 GMT
From: William Reiken <[e-mail]>
Subject: Small Astronaut (was: Budget Astronaut)
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Joseph Askew) writes:
>
> I think you would lose your money. Julius was actually rather tall
> for a Roman.
>
    So just how tall was he?

                        Will...

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

Date: 7 Apr 1993 02:10:19 GMT
From: "David M. Palmer" <[e-mail]>
Subject: space food sticks
Newsgroups: sci.space

[e-mail] (;;;;RD48) writes:

>I had spacefood sticks just about every morning for breakfast in
>first and second grade (69-70, 70-71).

I remember these.  The TV commercial for them had an astronaut
eating one of them with his spacesuit and helmet on.  He stuck
it into his mouth through a neat hole drilled in his faceplate.
Very confusing for a little kid who knows about vacuum and the
horrors of a suit leak.

--
        David M. Palmer        [e-mail]
                    [e-mail]

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

End of Space Digest Volume 16 : Issue 430
------------------------------