Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V13_1/V13_161.TXT

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Subject: SPACE Digest V13 #161

SPACE Digest                                     Volume 13 : Issue 161

Today's Topics:
        Re: "Magnum" Electronic Intelligence Satellite
              Re: SPACE Digest V13 #099
              Re: Solar Impact Mission.
                   Salyut 7
              Re: SPACE Digest V13 #139
               Re: Controversy
             Galileo Update #2 - 02/14/91
              Re: SPACE Digest V13 #124

Administrivia:

    Submissions to the SPACE Digest/sci.space should be mailed to
  [e-mail].  Other mail, esp. [un]subscription requests,
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Date: 11 Feb 91 12:07:17 GMT
From: mcsun!ukc!icdoc!syma![e-mail]  (Nick Watkins)
Organization: University of Sussex
Subject: Re: "Magnum" Electronic Intelligence Satellite
References: <[e-mail]>
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From article <[e-mail]>, by [e-mail] (Henry Spencer):
> In article <[e-mail]> [e-mail] (Dave Smith) writes:

>>antenna "the size of a baseball field."  This sounds like a really large
>>structure to be deploying automatically.  Does anyone have any info
> What you've just said -- it's called "Magnum", it's an eavesdropping
> satellite, and it probably has a big deployable antenna -- is just about
> the sum total of unclassified knowledge about it.
And the best of the rest is in Des Ball's superb book, "Pine Gap"
[ Allen and Unwin Australia]. One of 3 main ground stations is in
Australia at eponymous Pine Gap.

Includes a nice sketch of a Lockheed design for a deployable large
antenna. Remember ATS 6 and imagine what you could do with another 10
years or so and a Shuttle payload bay (less IUS). Probably 2 in orbit,
possibly even 3 if last military Shuttle was 28 degrees -> GEO
not LEO (I don't know). Reportly it's follow on to the RHYOLITE/AQUACADE
series of Atlas Agena D (sic) launches in the seventies.

Nick
--

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Date: Tue, 12 Feb 91 17:46:33 EST
From: Tommy Mac <[e-mail]>
Subject: Re: SPACE Digest V13 #099
In-Reply-To: Message of Fri, 1 Feb 91 05:28:38 EST from
 <space-request+%ANDREW.CMU.EDU@CARNEGIE>
To: [e-mail]

Re: Richard B. Augusts request about gas extraction from rocks.

I don't know if this counts or not.  I found a book, SPACE RESOURCES that talks
about using gases to extract metals.  It covers other resources as well, such
as o2,h2,n2,and n2, but the focus is on metals and energy.

CRC has a SPACE INDUSTRIALIZATION manual.  Two volumes.  The first covers mater
ial and energy resources.  The second covers vehicles.  It also has an extensiv
e bibliography in case it isn't what your looking for.

Good Luck.  Both are fascinating reading, if you can handle not-to-intensive
technical jargon.

Tommy Mac    -For, lo, I will cause to come up against Babylon an assembly of
1804tm@msu.   great nations from the North country: and they shall set them-
bitnet        selves in array against her; from thence she shall be taken:
              their arrows shall be as of a mighty expert man.  -jeremiah 50,9
Acknowledge-To: <18084TM@MSU>

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Date: 5 Feb 91 18:50:21 GMT
From: udecc.engr.udayton.edu!blackbird.afit.af.mil!lonex.radc.af.mil![e-mail]  (Disaster Preparedness)
Organization: Rome Laboratory (US Air Force), Griffiss AFB, NY
Subject: Re: Solar Impact Mission.
References: <[e-mail]>, <[e-mail]>, <[e-mail]>
Sender: [e-mail]
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In article <[e-mail]> [e-mail]
writes:
>In article <[e-mail]>, [e-mail]
>(Henry Spencer) writes:
>> ....
>>
>> For really tight turns, what you want is a waverider design that can fly
>> at high hypersonic speeds in an atmosphere.  Then you can do a right-angle
>> turn or even a 180 around any planet with a substantial atmosphere, e.g.
>> Venus.  Aerodynamic forces do a much better job of holding you down during
>> the turn than gravity.  This also lets you use Mars rather than Jupiter
>> for outer-planets missions, which is nice because Jupiter's Van Allen belts
>> are a major hassle for Jupiter gravity assists.
>> --
>
>I've heard about this kind of thing-- it sounds like a neat idea although
>the aerodynamics of going that fast through an atmosphere would be rough,
>not to mention the materials the waverider would have to be made out of.
>Also, you'd better carry along big thrusters for correcting any errors
>made in the manuever.  Anyone in netland doing any research with high
>velocity waveriders?
>
>One of the more interesting waverider missions I've heard of was using Mars for
>a gravity assist to get out to Pluto.  I don't have the velocities handy,
>but I remember the time figure as being about 4 years to go from Earth to
>Pluto using that kind of trajectory.
>
>---

     These are very interesting ideas that, I agree, would allow a probe
to change its direction in a hurry.  The problem I see is that when the
vehicle enters an atmosphere, it loses kinetic energy in favor of thermal
energy.  The idea of using this aero-assist method would seem to work okay
for a solar impact mission, but I don't see how a probe could reach Pluto
in four years after losing kinetic energy.  Does it kind of bounce off
of the Martian atmosphere and gain a whole bunch of kinetic energy somehow
(not at all obvious to yours truly)?  Or does the probe's proximity to the
planet allow for a greater gravitational kick that more than overcomes the
loss to heat?  Whatever the reason, I'm certain Mr. Spencer can set my
misgivings straight.

- Andy

*******************************************************************************
* Harold G. "Andy" Andrews II, 1Lt, USAF *  "Many the man whose punctuality   *
* [e-mail]             *   serves only to warm his chair."  *
* Rome Laboratory/IRRE (USAF/AFSC/ESD)   *                                    *
* Griffiss AFB, NY USA 13441-5700        *    -- Leonard somebody or other    *
* [phone] (AVN prfx 587)          *  (Not an official USAF viewpoint)  *
*******************************************************************************

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Date: 6 Feb 91 21:11:26 GMT
From: att!linac!pacific.mps.ohio-state.edu!zaphod.mps.ohio-state.edu!sdd.hp.com!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Organization: Jet Propulsion Laboratory, Pasadena, CA.
Subject: Salyut 7
Sender: [e-mail]
To: [e-mail]


     The latest word about Salyut 7 from the U.S. Space Command is that it
will re-enter the atmosphere over the Mediterranean Sea today (February 6)
at about 8:15 PM (PST).  This prediction has an uncertainty of plus or
minus two hours.  If the prediction holds true, then Salyut 7 will be
over northern Italy as it make its entry, and any debris reaching Earth
would fall over Eastern Europe or the Soviet Union.  It is also unlikely that
the troops in the Persian Gulf would be able to see the expected fireball.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|      Ron Baalke         | [e-mail]
     | | | |  __ \ /| | | |      Jet Propulsion Lab |
  ___| | | | |__) |/  | | |___   M/S 301-355        | It's 10PM, do you know
 /___| | | |  ___/    | |/__ /|  Pasadena, CA 91109 | where your spacecraft is?
 |_____|/  |_|/       |_____|/                      | We do!

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

Date: 15 Feb 91 02:17:40 GMT
From: sdd.hp.com!spool.mu.edu!news.cs.indiana.edu!uceng!minerva![e-mail]  (Daniel Mocsny)
Subject: Re: SPACE Digest V13 #139

In article <[e-mail]> [e-mail] writes:
>At current launch prices, with current safety considerations, and current lack
>of experience, 17% just isn't good enough.  Maybe if Galileo discovers some
>marketable material....or maybe, unbeknownst to anyone, magellan has dropped
>a starting colony of Blue-green algae, which will begin converting Venus'
>atmosphere to O2....

The key is probably to package the starting "seed" for your space
infrastructure into something smaller. Like one completely
self-replicating robot. Drop it on a large rock, then come back
in twenty years when it has exponentiated itself into whatever
infrastructure you want.

Or perhaps evolved into someone who doesn't remember you... :-)

>Fun to dream, but meanwhile, we'll have to depend on the Gov.  That's just how
>air travel got started.  People didn't believe that planes were safe.  So, the
>feds awarded (name forgotten) a mail contract.  Thus was born the industry that
>eventually became Federal Express.

This analogy overlooks a serious difference of scale. How large was the
federal mail contract as a fraction of USA GNP at the time? Was the
government taking a risk then that would be comparable to a
$400,000,000,000 investment today? I.e., if the airplane had failed
disastrously as a mail carrier, would the national economy have
collapsed? Also, how much of a hit were the feds taking with the
airmail contract compared to their rail, etc. contracts? And how long
did the venture require to become profitable?

Can you name ANY government that has ever risked that kind of
investment (proportional to its resources) on an unproven venture with
a similar payoff time?

Also, using the airplane as a mail carrier was a trivial application of
existing technology. Airplanes had long been proven capable of
transporting similar loads similar distances with similar schedules.
(If someone had handed out the contract in 1905, that would have been
a different story.)

Space development on the O'Neill scale is not a trivial application of
existing technology. While all the individual pieces appear workable
and not too dramatic, let us not forget the lesson of Hubble. You just
never know what's going to happen to a big, complex system when you
plug it all together. Big systems don't come from little systems solely
by multiplying everything by 1.0e+5.

You are quite correct that the government has played a central
role in the development of essentially ALL modern transportation
infrastructure, most power-generation infrastructure, etc. (Either in
administration, subsidies, guaranteed monopolies, underwriting
research, etc.) We can reasonably conclude that space development of
any kind without government involvement is unlikely, at least in the
near term.



--
Dan Mocsny
Internet: [e-mail]

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Date: 14 Feb 91 22:22:19 GMT
From: sdd.hp.com!samsung!munnari.oz.au!metro!tplrd![e-mail]  (Martin Brown)
Organization: Telectronics Pacing Systems
Subject: Re: Controversy
References: <[e-mail]>, <[e-mail]>, <[e-mail]>
Sender: [e-mail]
To: [e-mail]

On the issue of how they produced live TV transmission of Armstrong taking
the first step on the moon:

> I'm thinking of the black and white, very low-fidelity, real-time video
> that was broadcast from the LEM as Armstrong descended the ladder for the
> first time.  It was shot from a B/W tv camera in an equipment bay on the
> side of the LEM.  [e-mail]

As I understand it, this camera's main aim was to give a visual indication
of how far into the lunar surface the LEM's feet had sunk. The ability of
the lunar surface to support the LEM (or human beings) was unknown at the
time. It turned out that the LEM feet didn't sink into the dust as much as
expected hence the jump of a couple of feet from the bottom of the ladder
onto the lunar surface.

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Date: 15 Feb 91 01:50:44 GMT
From: swrinde!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Organization: Jet Propulsion Laboratory, Pasadena, CA.
Subject: Galileo Update #2 - 02/14/91
Sender: [e-mail]
To: [e-mail]


                          GALILEO STATUS REPORT
                           February 14, 1991

     As of noon (PST) Thursday, February 14, 1991, the Galileo spacecraft is
30,440,670 miles from the Earth and traveling at a heliocentric speed of
78,590 miles per hour; distance to the Sun is 91,968,810 miles (0.99 AU).
Round trip light time is 5 minutes, 24 seconds.

     A command was successfully sent on February 11 to reset the Command Loss
Timer to 240 hours, its planned value for this mission phase.

     Four more sun acquisition activities were successfully completed on
February 8, 10, 12 and 14.  To date, sixteen sun acquisitions out of the 17
planned in VE-12 (Venus-Earth 12 sequence) have been completed.

     Two USO (Ultra Stable Oscillator) calibration tests were successfully
completed on February 8 and 12.  These tests provide trend information to
characterize this ultra-stable downlink frequency source.

     A Cruise Science Memory Readout (MRO) was successfully completed on
February 13 for the DDS (Dust Detector) and MAG (Magnetometer) science
instruments.

     The VE-14 sequence memory load was successfully transmitted and received
by the spacecraft on February 14.  The VE-14 sequence controls spacecraft
activities from February 18 to April 29, 1991.  In addition to normal routine
operations such as sun acquisitions, SITURNS, RPM (Retro Propulsion Module)
flushing, telecommunications tests and science MRO activities, this sequence
contains the HGA (High Gain Antenna)_ deployment and LGA-2 (Low Gain Antenna-2)
retraction activities as well as windows for the TCM-9B (Trajectory Correction
Maneuver 9B) planned for March 19 and 20.

     The AC/DC bus imbalance measurements exhibited some activity.  The AC
measurement fluctuated 2 DN and now reads 45.4 volts.  The DC measurement
dropped 24 DN and now reads near 8.4 volts.  The large drop occurred while
the spacecraft was quiescent and not being tracked.  All other power-related
telemetry and spacecraft telemetry are normal.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|      Ron Baalke         | [e-mail]
     | | | |  __ \ /| | | |      Jet Propulsion Lab | Is it mind over matter,
  ___| | | | |__) |/  | | |___   M/S 301-355        | or matter over mind?
 /___| | | |  ___/    | |/__ /|  Pasadena, CA 91109 | Never mind.
 |_____|/  |_|/       |_____|/                      | It doesn't matter.

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

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Date: Thu, 14 Feb 91 18:12:39 EST
From: Tommy Mac <[e-mail]>
Subject: Re: SPACE Digest V13 #124
In-Reply-To: Message of Thu, 7 Feb 91 02:39:40 EST from
 <space-request+%ANDREW.CMU.EDU@CARNEGIE>
To: [e-mail]

in space Digest #124, Nick szabo finally made a distinction between
space STATIONS and Space SETTLEMENTS.  Nicks defintion is rouhgly:

                                   Station                   Settlement

     crew                           1-20                      100's
% of supplies from  Earth           90% +                     10% or less
self-supporting ($)               absolutly not            makes money

Well, Nick, based on these definition, I agree, we should move on to making
space settlements, or what I think of as a space station.  To bad the feds
don't agree.

Nick also pointed out that DeGama, during the days of Magellan and Columbus,
was pulling down some decent money running spices.

     In other words, Nick, you missed my point.  I was asking you to compare
     the cost of moving into a new environment then, to the cost now, Not how
     much money they made then.  So I have my names wrong.  Maybe you could use
     your better knowledge of that time to make a valid comparison.  Also, why
     don't you direct me to a history of that time.  I haven't found a good
     history of the age of exploration.

Re; fish-to-amphibian, tree-to-savanna.
Nick says that these comparisons wouldn't be valid, seeing as they didn't do it
voluntarily.

       Too bad we don't have much choice either.  Without space resources, our
       world degenerates into a zero-sum game.  (See malthus).  and we have
       the power of nuclear weapons now.  I'll let you imagine the alternative.

       Maybe the amphibians did have a choice, as well as all those extinct
       species that didn't make the choice.

Before you judge this comparison invalid, remember:

       Our bodies are mostly water.  Amphibians developed a new kind of skin to
       keep the cells in their body in the same environment that they had left.
       Evidence of this is our moist eyes, lungs, etc.
If we move into space, we will have to develop a new kind of skin to keep us in
the same environment that we had left (i.e. air)
       To a fish in the water, air would seem a total vacuum, but it isn't.
To a person in the air, space would seem a total vacuum, but it isn't.
       The first cells (it is hypothesized) were heterotrophs.  That is, they
       ate complex organics for their energy and materials.  If some cell had
       not evolved photosynthesis, eventually all the "soup" would have been
       eaten, and then the cells would die.
The first intellignet civilization uses complex organics for their energy (oil,
coal, gas)  if we don't develop photosynthesis (SPS-like system), we'll use all
our energy, and, at the least, make getting into space impossible.  The long-
term bad news is that the Sun will die.  The short term bad news would be our
own actions on the biosphere and ourselves.

I stand by the benefits of the things learned on MIR.  For example: did you
know that someone talking to you from zero-gee is not being sarcastic, but is
simply experiencing a puffy face?  This kind of thing is important for the
efficiency that you continue to espouse.  Communication can cut efficiecy to
ZERO with no trouble at all, when it fails.

Nicks assumptions that Tom doesn't accept :

                We will do the efficient stuff right away because it makes the
                most sense.

I wish we would.  But the guys with the cash don't like the risks.  Things like
succesful space stations will convince them the risk is less.
 And things like valuable materials or efficient energy-conversion will help
convince them that the benefits are more.  Till they cough it up, were stuck
with paltry stuff that can barely demonstrate what we need to do.

About the Japanese:  I was kidding, though I may actually take it up when it
comes time to start looking for employment.  I'm still two years from gradimica
ting.  So what did you say, anyway?

Tommy Mac-
Acknowledge-To: <18084TM@MSU>

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End of SPACE Digest V13 #161
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