Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V13_1/V13_191.TXT

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Subject: SPACE Digest V13 #191

SPACE Digest                                     Volume 13 : Issue 191

Today's Topics:
             Re: Martian mystery?
        Re: Confusion regarding "Firm Fred Decisions"
     Re: Commercially-funded Space Probes (was Re: Space Profits)
         NASA Headline News for 02/22/91 (Forwarded)
             Re: Terraforming, sun shield
             Re: Terraforming, sun shield
         Re: Technology transfer info request

Administrivia:

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

Date: 22 Feb 91 13:50:28 GMT
From: haven!wam!cville.umd.edu![e-mail]  (Robert David Bunge)
Subject: Re: Martian mystery?

Rolf Meier mentioned how it is easy for the human mind to find familar shapes
in abstract designs and how people looking at Viking photos found letters,
faces, etc..  I agree.  A couple of years ago while giving several talks on
Mars to the public for my astronomy club I tried a simple experiment.  I gave
two talks a night for three nights, each time showing the same slides,
including Viking 2 lander shots of the surface.  During the first talk, the
question of the "face" came up.  I put up the Viking 2 lander shot and asked
people to point out interesting shapes.  They (about 70 in the audience)
found three faces (including one wearing a baseball hat) a few letters and
numbers and the outline of a car.  I did the same thing during the following
talks and each time the audience found the same three faces, two of the letters
and the car.  It wasn't very scientific, but it sure convinced me as to how
fertile the human mind is when it comes to assocations.

Since then, on two occasions I've come across people who are very serious about
the "face."  On one, I was able to have the person do the same thing as above
and he found several of the same features.  I hope I helped to change his
mind (either that or I totally convinced him that there is life on Mars!)

Bob Bunge
[e-mail]

:wq

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

Date: 22 Feb 91 18:54:26 GMT
From: sdd.hp.com!cs.utexas.edu!news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Confusion regarding "Firm Fred Decisions"

In article <[e-mail]> [e-mail] (Charles Frank Radley) writes:
>>    Large doors will be required, where will they go ?
>-
>   You quote me out of context.   By door I clearly meant
>airlock which was the discussion I then presented at length.

However, you focus at length on the problems of cutting openings, not of
putting airlocks in them.  Anywhere you can bolt a hatch you can bolt an
airlock instead, without any fundamental difficulties.

>+ The ET already has access manholes, which are not as large as
>+one would like
>-
>    You can say that again

Actually, they're not bad.  To be specific, the liquid-hydrogen tank has
*two* 36-inch manholes in its base, plus a third that opens on the intertank
space.  The LOX tank has one, again in the intertank space.  This actually
should suffice for a lot of things, although it might be necessary to move
some interior equipment to make both of the hydrogen-tank-base manholes
usable.

As I may have mentioned before, the people working on the Gamma-Ray Imaging
Telescope concept have already sorted out the details of opening one of
the hydrogen-tank manholes and getting both men and equipment in through
it.  No major problems, last I heard.

>+ but should suffice for a lot of things.  Nobody builds a
>+tank that  size without a way in for work and inspection.
>-  And nobody builds a tank with airlocks in it.

Unbolt a manhole, slide in an airlock with a mounting flange matching the
outer rim of the manhole cover, and bolt it down.  Bingo.

>+  (Similarly, access to  Skylab was via what was originally an
>+access manhole in the S-IVB's  liquid-hydrogen tank.)
>-
>   Skylab was launched with the inspection hatches sealed off and
>a purpose built airlock.   And I believe access for the
>outfitting of the internal equipment was achieved through the
>open end prior to installing the bulkhead.   Kinda tricky doing
>all that through little one man inspection hatches.

A 36-inch hatch is not particularly "little".  As for Skylab, the access
manhole in the top dome of the hydrogen tank was not "sealed off"; it
was in fact where the airlock module was attached.  The fitting of the
internal equipment was originally to be done through the manhole, but
after the final "dry workshop" plan was adopted, an access door was added
in the side.  This was a convenience rather than a requirement.  Said door
was indeed sealed before launch.

(References:  "Living and Working in Space" (NASA SP-4208) and the Skylab
news reference.)

> >Breaching the intertank between the H2 and the O2 tanks is a
> >no-no...
>
>+   ???  Access to the intertank area, as with the tanks
>+themselves, is already  provided for...
>-
>   My original staement was correct as written.

Your original statement was obscure and possibly incorrect as written.
You need to give a bit more detail to justify it.  There is a 46x52-inch
access door in the side of the intertank structure (ref:  Space Shuttle
news reference), although I believe this is under the sprayed-on insulation
when delivered for flight.  Please be specific about *why* "breaching" this
area is "a no-no".
--
"Read the OSI protocol specifications?  | Henry Spencer @ U of Toronto Zoology
I can't even *lift* them!"              |  [e-mail]  utzoo!henry

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

Date: 22 Feb 91 21:37:16 GMT
From: usc!sdd.hp.com!zaphod.mps.ohio-state.edu!rpi![e-mail]  (Jim Kasprzak)
Subject: Re: Commercially-funded Space Probes (was Re: Space Profits)

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] (Charles Frank Radley) writes:
>>  Unfortunately you are too late.   The United Nations Treaty on
>>the Activities of States on the Moon and all Celestial Bodies,
>>already prohibits the private property rites which you address.
>
>This is the "Moon Treaty" which Brian in fact mentioned.  Fortunately,
>it has been ratified by almost nobody, and in particular the US has not
>ratified it and isn't going to.  It's effectively dead.  All glory to the
>late, lamented L5 Society, which singlehandedly killed it, saving space for
>free men and thereby earning the undying hatred of the US State Department.

 What did the State Department have against this? I'd think that the
US government would be glad to see the death of such a treaty, since
the US was (and probably still is) one of the few countries in a
position to actually reap some profit from the commercial development
of space.
--
 Jim Kasprzak          [e-mail] (internet)
 RPI, Troy, NY         [e-mail]
 "A spirit with a vision is a dream with a mission."  -Rush

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

Date: 22 Feb 91 22:36:45 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: NASA Headline News for 02/22/91 (Forwarded)


             Headline News
Internal Communications Branch (P-2) NASA Headquarters

  Friday, February 22, 1991    Audio Service: 202 / 755-1788

This is NASA Headline News for Friday, February 22, 1991

Kennedy Space Center launch team staff are proceeding with
preparations for Shuttle Mission STS-39.   Analysis of hinge cracks on
Discovery's fuel line door mechanisms continues.  The launch team began
hypergolic fuel loading into the orbital maneuvering system tanks last night.
No decision on whether to fly "as is" or bring Discovery off the launch
pad for repairs has been made yet.

As part of this ongoing analysis, a door closure test is scheduled for late
this weekend on Columbia's fuel door mechanisms.  This test and
analysis of the results are expected to be complete in time for management's
assessment at the STS-39 Flight Readiness Review.

Atlantis and Columbia have been examined to determine if similar
conditions exist on their door mechanisms.  No cracks have been found in
the ET door mechanism on Atlantis, now scheduled to launch in April on its
Gamma Ray Observatory deployment mission.  Inspection of the door
mechanism on Columbia has revealed three small cracks.  Analysis of
Columbia's situation continues.

                   * * * * * * * * * * * * * * * *

Scientists, using new data provided by the Magellan spacecraft, are
currently testing four competing theories concerning the nature of the
continent-sized highland region on Venus known as Aphrodite Terra.
Aphrodite Terra, the largest of the Venus' highland regions, extends nearly
two-thirds of the way around the planet.  Magellan has completed radar
mapping of this region.  Earlier data provided by Pioneer Venus Radar
Mapper suggested that Aphrodite Terra's regional topography might be
similar to Earth's continents.

The four current hypotheses state that the highland region is: 1)  An ancient
continent, formed from lighter rock that crystallized early and literally
floated on Venus' dense mantle; 2)  A spreading ridge analogous to the mid-
ocean ridges on Earth where new crust is being formed as the continents drift
apart; 3)  A hot spot similar to the hot spots beneath the island of Hawaii
where the mantle is rising, producing broad domes; and 4)  A region of
mantle downwelling where a plume of colder, more dense mantle material
causes the surface crust to compress and thicken allowing the thicker region
to stand higher.

Advocates of all four hypotheses are members of the Magellan science team
and have created a continuous "lively debate" according to project scientist
Steve Saunders.

                   * * * * * * * * * * * * * * * *

As a continuation of NASA's support for National Engineers Week,
Adm. Truly will teach a ninth grade geometry class at George
Washington Junior High School in Alexandria this afternoon.  Adm. Truly
will tell students how math and science relate to the exploration of space and
show the students how engineering can turn ideas into reality.


Here's the broadcast schedule for Public Affairs events on NASA Select TV.
All times are Eastern.  NASA Select TV is carried on GE Satcom F2R,
transponder 13, C-Band, 72 degrees W Long., Audio 6.8, Frequency 3960
MHz.**indicates a live program.

Monday 2/25/91
     9:00 am    STS-37 flight director mission briefing,
                        live from Johnson Space Center.

    10:00 am    Gamma Ray Observatory science and
                        spacecraft briefing, live from Goddard
                        Space Flight Center.

     2:00 pm    STS-37 flight crew briefing, live from  JSC.



All events and times may change without notice.  This report is filed daily,
Monday through Friday, at 12:00 pm, EST,  It is a service of NASA
Headquarters Office of Public Affairs.  Contact:  CREDMOND on NASAmail
or at 202/453-8425.

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

Date: 22 Feb 91 22:34:20 GMT
From: rochester![e-mail]  (Paul Dietz)
Subject: Re: Terraforming, sun shield

In article <[e-mail]> [e-mail] (Jonathan Leech) writes:

> [ analysis of blowing Venus's atmosphere off using comet impacts ]

I've suggested before that nuclear explosives would be cheaper.  The
binding energy of Venus's atmosphere is about the same as the energy
released by completely fusing to helium-4 about 10^8 tons of
deuterium.  The idea would be to use a large number of explosive
devices to quickly heat the atmosphere to several 10^4 K.  The
atmosphere would then expand upwards, accelerating to > escape
velocity as it cools.  A naive back of the envelope calculation
suggests radiative losses would be tolerable over the tens of minutes
required for the atmosphere to expand to ~ 1 planetary radius.

10^8 tons is about the amount of deuterium in Venus's atmosphere, I
think (deuterium there is greatly enriched relative to protium, BTW),
so it would be nice to be able to use explosives burning more common
isotopes.  That might be possible in very large bombs, where the
square/cube law lets slower reactions go farther before disassembly.

[ BTW: comet impacts would likely use comets in retrograde orbits,
  so the impact velocity would be > 20 km/s. ]

    Paul F. Dietz
    [e-mail]

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

Date: 22 Feb 91 18:45:57 GMT
From: maverick.ksu.ksu.edu!ux1.cso.uiuc.edu!bradley.bradley.edu!buhub![e-mail]  (Craig Levin)
Subject: Re: Terraforming, sun shield

In <[e-mail]> [e-mail] (Henry Spencer) writes:

>Well, not really, if what you want is a habitable planet.  If you think
>90 atmospheres of CO2 with clouds made of sulfuric acid droplets is a
>hostile environment, 90 atmospheres of *oxygen* has it beat in spades.
>High-pressure oxygen is corrosive almost beyond imagining, especially
>when hot.  The real problem with terraforming Venus, far more significant
>than the shortage of water or the nearness to the Sun, is the need to get
>rid of most of the atmosphere somehow.

    Could one use close approaches by minor planets or comets to
somehow plow off the atmosphere? I mean, if we're at a level where
you're considering huge sheets of Mylar up there, we can definitely
tug around a few comets here and there.

Craig\The Moonman\Levin      ***[]***  ///////
[e-mail]       )`-----//
The Stars-Our Destination!       ```````

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

Date: 21 Feb 91 23:56:29 GMT
From: usc!zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!pitt!nss![e-mail]  (Paul Blase)
Subject: Re: Technology transfer info request


 JD> This is a request for my daughter who is doing an advanced high
 JD> school project on technology benefits from space, i.e., how has
 JD> the space program helped improve life on earth?  We have the
 JD> standard NASA handouts but are looking for deeper information,
 JD> especially describing *recent* examples of technology benefits,
 JD> say, in the last 3-4 years.

Write to
Director, Technology Utilization Division,
Office of Commercial Programs,
NASA Headquarters, Washington, D.C. 20546
and request a copy of NASA's "Spinoff" book (published yearly).  It goes
into detail on the commercial spinoffs from space technology.

You can also contact the NASA Scientific & Technical Information Facility,
P.O. Box 8757, Baltimore, MD 21240-0757; [phone], ext 245

Go to a library and see if you can find the latest copies of
"NASA Tech Briefs".  This magazine lists the results of projects recently
accomplished under NASA auspices, and how to get reports on and license
the technology

One of the primary items in NASA's charter is that all of the technology
developed under its auspices must be made available to the public (as
opposed to the military, which hides it as long as possible).  A point that
I have been making for some time is that the really advanced R&D that drives
technological advance is VERY expensive and, in general, no private company
(with the possible exception of Bell Labs) can afford (or is willing to risk)
the 10-20 year lead times and the billions of dollars necessary.  By advanced
R&D I mean not only the research that is done at places like FermiLab but
taking that abstract knowledge and building something with it.  In general,
building the first piece of equipment to use some field of knowledge (the
first RADAR, the first computer, the first composite wing, the first
liquid hydrogen/liquid oxygen rocket engine) is the riskiest; after the
engineers figure out how to do it, building commercial applications is much
easier.

The only organization capable of supporting this long-term R&D is the U.S.
government, and the only government organizations doing so are NASA and the
military.  In war, the side with the most advanced tools wins (see the
laser-guided bombs and such being used in the current Persian Gulf conflict).
Aircraft, RADAR, radio, computers, all were initially developed with
military funds.  The problem with the military (setting aside any moral
questions) is that it tends to classify everything for as long as possible.
A not uncommon occurance is for a company to redo several years of research
that it knows has already been done at a military facility - but cannot get
at because of security.  In addition, when military budgets are slashed (as
is happening) R&D tends to be among the first to go.

This leaves NASA as THE prime source of advanced technology to drive U.S.
industry.  NASA has sponsered research into advanced materials (particularly
advanced alloys, composite materials, and plastics), all forms of
aerodynamics, advanced propulsion (reflected in most of the engines now
used by the airlines), cryogenics, computers (the computer industry would
probably be 10 years behind where it is now without Project Apollo and its
guidence systems), optics, and human-factors (how to build things so that
people can really use them efficiently).  People often refer to spinoffs
as one of the nice things about NASA, and then wonder how we can spend money
exploring space.  I say that spinoffs are one of NASA's main justifications
for existance, and that lacking them, we might as well start learning
Japanese right now.


--- via Silver Xpress V2.26 [NR]
--
Paul Blase - via FidoNet node 1:129/104
UUCP: ...!pitt!nss!Paul.Blase
INTERNET: [e-mail]

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

End of SPACE Digest V13 #191
*******************