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Subject: SPACE Digest V12 #97

SPACE Digest                                      Volume 12 : Issue 97

Today's Topics:
                   Re: EOS
        Re: Is an asteroid capture possible/feasible?
              Re: Titan boosters
        Re: Is an asteroid capture possible/feasible?
         Re: Galileo encounters with Venus and Terra
 NASA to feature aeronautics and space at EAA convention (Forwarded)

Administrivia:

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

Date: 18 Jul 90 02:28:49 GMT
From: usc!samsung!munnari.oz.au!uniwa!vax6![e-mail]  (Liam Gumley)
Subject: Re: EOS

In article <[e-mail]>, [e-mail] (Steve Emmerson) writes:
> In <[e-mail]> [e-mail] (Liam
> Gumley) writes:
>
>>In article <[e-mail]>,
> [e-mail] (David Anderman) writes:
>
>>> If EOS becomes a big project, NASA will screw it up.
>
>>However, this does not mean that NASA will screw it up.  NASA has for the last
>>30 years or so taken the lead in fostering initiatives in satellite remote
>>sensing of the earth. This has led, among other things, to the operational use
>>of weather satellites.  It has involved a high level of interaction between
>>NASA and other research institutions.  The trend in the past seems to have been
>>that NASA sponsors the development of experiemntal platforms (e.g. the early
>>ATS, TIROS, Nimbus) and instruments, which are then upgraded to 'operational'
>>status (e.g. GOES, GMS, TIROS-N/NOAA).  When you consider that these days it
>>takes the best part of 100 million US dollars and 5 to 10 years to develop,
>>test, and launch a major earth remote sensing payload, who else is capable
>>except NASA ?
>
> For smaller projects, I know several institutions that could -- and have.

You are certainly correct that for smaller experimental payloads, there
are plenty of institutions that can do the job.  However for EOS we are
talking about a major new initiative, taking some current experimental
sensors e.g. ocean color scanners, atmospheric CO2 sensors and making them
'operational', as was done with GOES and the TIROS-N/NOAA series.  There are
also experimental sensors for EOS designed to answer new science questions.

>>> Furthermore, NASA will make EOS into a technology development program,
>>> rather than an applications program.
>
>>Technology development runs in parallel with the development of new remote
>>sensing instruments for particular science missions.  For example if you want
>>to fly a Michelson interferometer onboard a spacecraft to sense atmospheric
>>temperature, moisture and trace gases, you need to develop infra-red detector,
>>laser, cryogenic,  electronics and data communication technology to do it.
>>However the technology developement is not the point of EOS.  The point is that
>>there are some very important questions about the nature of the earth
>>environment that need prompt investigation.
>
> One of the problems from a user's (i.e. meteorologist's or
> oceanographer's) perspective is that the increasing size of the
> projects causes them to become relatively insulated from the user
> during design and implementation -- the project becomes so large that
> it's simply no longer feasible to have a significant amount of
> scientific oversight (and veto power!) on the design process.  There
> are simply too many cooks.
>
> Smaller projects tend not to suffer from this problem.  (Fewer cooks).

I am in the meteorology/oceanography game, so I am well aware of the problems
inherent in obtaining the 'ideal' data to help answer a given science question.
However the smaller the input to the design of a given sensor, the more
specialised it is likely to be.  You need to have input from a number of
sources in order to design a sensor which will meet all the required needs.
Take for example a next generation atmospheric temperature sensor.  You need
input from the National Weather Service on the required accuracy of the
temperature soundings.

> Another problem is that large projects have a tendancy to incure cost
> and time overruns, which are very bad when attempting a prompt
> investigation.

Absolutely.  There must still be a place for small, experimental missions
designed to examine a particular problem.  However you must distinguish between
these type of missions and one such as EOS which attempts to answer a whole
range of questions about the Earth's biosphere.

> An example is the next-generation GOES satellite.  It's a three-axis
> stabilized platform rather than the original spin-stabilized platform.
> This design change has resulted in technical and cost-overrun problems
> and, furthermore, means that the scan lines can now overlap or even be
> unrelated to one another -- considerably increasing the complexity of
> the subsequent data analysis.  Yet, I haven't met a remote-sensing
> meteorologist or oceanographer who is happy with this change.

I certainly agree that there must be input from the eventual data users on
the design specs of a given sensor.  This is why the EOS instruments all have
science teams which are responsible for defining and guiding the sensor
science requirements.  (I'm getting on thin ground here - I'm not really that
close to the EOS operation...)  Don't get me wrong - I'm not saying that EOS
will be perfect, I am just uncomfortable with the argument that because NASA
is involved, the EOS mission will fail.

> It's almost as though: 1) people realize that a better system is
> theorectically possible and go for it -- failing to realize that the
> increased managerial overhead can result in a poorer product; and 2)
> the bureaucratic/industrial complex -- for reasons of its own --
> prefers large projects.

This is true to some extent.

>>Let's hear from some more remote sensing people on this, and other topics !
>
> I used to be in remote-sensing.  I would like to see more smaller
> projects -- each having more scientific oversight -- than currently
> exists.  I believe that this would be more cost effective and more
> scientifically efficatious.

From what I have seen in my somewhat limited experience, it seems that you
do need to keep pushing the limits of what you can do with space remote
sensors.  There is both a place for specialized smaller investigations driven
by universities for example, and large programs such as EOS which attempt
to address a whole range of problems.  One of the ideas behind EOS is to have
common data sources available which are accessible by meteorologists,
oceanographers, geologists, biologists etc. and to foster interaction between
these disciplines.

If you want some more info on EOS and Earth System Science, try and get hold of
a package put together by the Earth System Science Committee entitled
"Earth System Science - A Program for Global Change"  which addresses both the
science and technology issues involved.  I guess it should be available from
NASA Headquarters in Washington D.C.

I must say it does my heart good to see a bit of remote sensing discussion...

===============================================================================
| Liam E. Gumley                     "We've gone completely crazy!"   _--_|\  |
| Department of Applied Physics      - the Dodgey Brothers.          /      \ |
| Curtin University of Technology                                    \_.--._/ |
| Perth, Western Australia.                                                v  |
| Internet:[e-mail]                I think, therefore,      |
| Bitnet:[e-mail]    all opininons are my own.|
===============================================================================

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

Date: 18 Jul 90 11:53:29 GMT
From: mcsun!ukc!cam-cl![e-mail]  (Jonathan Hardwick)
Subject: Re: Is an asteroid capture possible/feasible?

In article <[e-mail]>, [e-mail] (Henry Melton) writes:
>  I have just moved my asteroid into a comfortable orbit and extracted
>  several tons of good quality iron from it.  Now, how do I get it
>  down on the surface of the earth, without spending a fortune.
>  Anybody got a good passive lifting body design or something that
>  would let me crash a big chunk of iron into a handy spot of desert
>  without vaporizing it or causing too much seismic activity?

Well, once the windtunnel boys have selected a lifting body shape, the
mechanics are easy...melt the metal in orbit (using eg solar mirrors),
foam it with any excess gasses you've got left over from the extraction
process, and then mould this metal foam into a lifting body shape.
Spray it with ablative foam (as suggested for astronaut emergency
return capsules) to reduce metal loss during descent, attach a couple
of braking rockets and a guidance computer, and you're away. Just hope
and pray that it doesn't crash on a city rather than your desert
landing site!  Actually, it might be better to land it in shallow
coastal waters, since this gives more margin for error and should
lessen the screaming of ecologists (deserts are very fragile
ecosystems; oceans are considerably more robust).  Then, cutting big
chunks off in shallow water wouldn't be a whole lot more difficult than
cutting big chunks off on land (think of the technology developed for
the offshore oil industry).  And if you *really* got it foamed up, the
thing would float, which means you could land it way out in the ocean,
hook up a tug, and tow it to the nearest market place.

Uhh, large doses of technological assumptions throughout the above. I
think I originally read of this notion in "Spaceships of the Mind".

Jonathan Hardwick, Cambridge University Computer Lab

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

Date: 16 Jul 90 22:30:39 GMT
From: usc!elroy.jpl.nasa.gov!zardoz.cpd.com!dhw68k!ofa123![e-mail]  (David Anderman)
Subject: Re: Titan boosters

Concerning the vibrations on a Titan launch: the excessive vibrations
are caused primarily by the SRBs, which are employed on the Commercial
titan, and the Tian IV. All humans launched to date on Titans were
launched by the Titan II, which did *not* employ SRBs....


--
David Anderman
Internet: [e-mail]
BBS:      714 544-0934   2400/1200/300

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

Date: 18 Jul 90 15:44:19 GMT
From: usc!cs.utexas.edu!news-server.csri.toronto.edu!helios.physics.utoronto.ca!physics.utoronto.ca![e-mail]  (Christopher Neufeld)
Subject: Re: Is an asteroid capture possible/feasible?

In article <[e-mail]> [e-mail] (Henry Melton) writes:
>I have often wondered:
>
>    I have just moved my asteroid into a comfortable orbit and extracted
>    several tons of good quality iron from it.  Now, how do I get it
>    down on the surface of the earth, without spending a fortune.
>
   Well, I saw a plausible scheme in a science fiction book a while ago,
_Thunder Strike_ by Michael McCollum (a good book about deflecting
comets and space mining).
   The scheme used to return iron to the Earth was to produce a foam of
the material in orbit, and then drop it into the ocean. The foamed metal
had lower density than water, and bobbed to the surface where it could
be grappled and towed to land. No cargo carriers, no sophisticated
electronics, no reaction thrusters, just a push from space to drop it
onto the watery hemisphere of the planet. You'd lose some mass to
ablation, but with such a low density foam it would slow down in the
lower atmosphere.

>Henry Melton ...!cs.utexas.edu!ut-emx!hutto!henry
>1-512-8463241 Rt.1 Box 274E Hutto,TX 78634


--
 Christopher Neufeld....Just a graduate student  | "The eagle may soar, but
 [e-mail]    Ad astra! | the weasel never gets
 cneufeld@{pro-generic,pnet91}.cts.com           | sucked up into a jet
 "Don't edit reality for the sake of simplicity" | engine."  Simon & Simon

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

Date: 18 Jul 90 16:30:27 GMT
From: news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Galileo encounters with Venus and Terra

In article <[e-mail]> [e-mail] (Byron Han) writes:
>Did we get any telemetry from the Venus encounter, scientific data and/or
>images?  Are there plans to do any of this with the two Terran flybys?

Yes, to both.

Incidentally, in English, the name of the planet is "Earth". :-)
--
NFS:  all the nice semantics of MSDOS, | Henry Spencer at U of Toronto Zoology
and its performance and security too.  |  [e-mail]   utzoo!henry

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

Date: 18 Jul 90 17:22:10 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: NASA to feature aeronautics and space at EAA convention (Forwarded)

Mary Sandy
Headquarters, Washington, D.C.                      July 18, 1990
(Phone:  [phone])


RELEASE:  90-99

NASA TO FEATURE AERONAUTICS AND SPACE AT EAA CONVENTION

     NASA returns to Oshkosh, Wis., July 27-Aug. 2 for the 38th
Annual Experimental Aircraft Association (EAA) International Fly-
In Convention and Sport Aviation Exhibition with a new exhibit
entitled "NASA: Technology for America's Future."  The exhibit
will showcase the technologies being developed for future flight
vehicles for safer, more efficient flight and for space science
and exploration.

     A highlight of the exhibit is the NASA/USAF X-29 forward-
swept-wing research aircraft, scheduled for one of its first
public displays away from its Southern California base.  NASA's
participation also includes the return of technical forum
speakers and the NASA craftsmanship display.

     Supporting the NASA exhibit are the agency's aeronautics
field centers, Ames Research Center, Mountain View, Calif., Ames-
Dryden Flight Research Facility, Edwards, Calif.; Langley
Research Center, Hampton, Va.; and Lewis Research Center,
Cleveland.

     Goddard Space Flight Center, Greenbelt, Md., will provide
its SARSAT van, a mobile exhibit that tells the story of the
Search And Rescue Satellite System.  NASA's AEROVAN traveling
aeronautics exhibit also will make an appearance.

     Throughout the 7-day convention, visitors to the NASA
exhibit will be treated to a wide range of display topics,
aircraft and spacecraft models and research hardware.

     The first X-29 jet research aircraft will be displayed in
front of the NASA exhibit building.  Its distinctive wing design
and other advanced aerodynamic, structural and avionic
technologies were tested during 242 flights over a broad range of
speeds.  A second X-29 continues to gather data on
maneuverability at high angles-of-attack (a nose-high attitude
relative to the flight path).

     There will be no aerial demonstration of the X-29 at the air
show.  Pilots and support staff will be available to answer
questions.

     Inside the exhibit building, visitors will see new vehicle
shapes, materials and propulsion concepts.  They will see how
advances in supercomputers give NASA researchers breakthrough
computational codes that can better predict flight performance.

     The exhibit will depict NASA's research on weather-related
safety factors such as icing, heavy rain and windshear avoidance,
as well as studies involving human interaction in the flight
process.

     The space science area will highlight NASA's Great
Observatories, four missions that may radically alter knowledge
about the universe.  And because humans will be assisted by
robots in performing many tasks associated with the operation of
Space Station Freedom, examples of recent achievements in
robotics technology will be displayed.  Vehicles being developed
for short-haul space transportation also will be exhibited.

     More than 2 dozen NASA speakers will participate in
technical forums during the EAA convention, covering subjects as
diverse as "Research Results Using the World's Largest Motion-
Base Piloted Simulator", "Environmental Aspects of the High Speed
Civil Transport" and "The Dream Continues - Back to the Moon and
On to Mars."

     Back by popular demand is a NASA craftsmanship exhibition
operated by technicians from Langley and Lewis research
centers.  The presentation spotlights fabrication crafts with
displays of selected metal and composite structures, aeronautical
models, test equipment and data measurement hardware.

     For 75 years, the research centers of NASA and its
predecessor agency, the National Advisory Committee for
Aeronautics, have led the world in aeronautical research and
technology development.  Today, NASA scientists and engineers
work closely with industry and universities to continue that
tradition, developing technology for America's future in
aeronautics throughout the speed regime from hover to hypersonic
flight.

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

End of SPACE Digest V12 #97
*******************