Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V10_1/V10_125.TXT

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Date: Mon,  9 Oct 89 01:50:14 -0400 (EDT)
Subject: SPACE Digest V10 #125

SPACE Digest                                     Volume 10 : Issue 125

Today's Topics:
         Re: Titius Series / Quantum orbits?
             Group 70, the glass is here.
            Re: The End of Galileo
           How the GALILEO mission may end.
      Eye Surgery and Low Pressure (was Re: Astronaut Selection)
         Re: How the GALILEO mission may end.
              Re: Gravity Assist
        Re: What to do with the $30 billion (missions)
                Gravity Assist
               Re: Astronaut Selection
----------------------------------------------------------------------

Date: 5 Oct 89 15:08:43 GMT
From: [e-mail]  (Beckman)
Subject: Re: Titius Series / Quantum orbits?

>I should mention where I read that the moons had an interesting series.
>It was in a book called "Einstein Plus Two" by Petr Beckmann.  This book
>is about Beckmann's theory, which, IMHO, looks like it might be able to
>challenge Einstein's theory of relativity.  In any case, it presents a
>very interesting theory and I recommend the book.  Has anyone else read
>it?

    Many thanks for recommending my book! A brochure will be sent to anyone
who asks for it at Golem Press, Box 1342, Boulder, CO 80306. Or leave your
USPS mailing address ([e-mail]) and I will send you one.
    I should add that the main point of the book is not the Titius series,
but the electron oscillations that can be derived directly from the Maxwell
equations, explain a lot of things, and contradict Einstein's interpretation
of the Relativity Principle.
    Petr Beckmann

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

Date: 5 Oct 89 22:08:11 GMT
From: hpda!hpcuhb!hpscdc![e-mail]  (Jack Zeiders)
Subject: Group 70, the glass is here.


    Group 70 status 10-5-89            10-05-89

    Yes we are still alive and well. The big news is the glass is
in San Francisco, in customs.  They don't believe there are no cocain
crystals that big. We hope to convince them it really was made in the U.S.
back in 1939 at Corning.

    For those who don't know we have rented a commercial space in
Hayward, and are going to start building the grinding machine there.

    The glass will be moved there next week or as soon as we can cut
through the red tape.

    More later

    Jack Zeiders
    [e-mail]
    !hplabs!hpscdm!jackz

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

Date: 4 Oct 89 18:12:30 GMT
From: [e-mail]  (David Palmer)
Subject: Re: The End of Galileo

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] writes:
>>I have read and heard about the Galileo spacecraft's 22 month mission
>>at Jupiter, which will end about October 1997.  Does anyone know what
>>will happen then?  ...
>
>It runs out of maneuvering fuel.  (In fact, with the precautions being
>taken to avoid problems with the slightly-buggy thruster design, it may
>end up having to sacrifice one of the asteroid encounters or one or two
>of the Jupiter-satellite encounters; the new maneuvering sequences are
>less fuel-efficient.)  No fuel, no attitude control, no antenna pointing
>for communication, finis.  The Voyagers had it easy; Galileo gets to do
>a *lot* of maneuvering, even with careful use of satellite gravity assists.

Also, cumulative radiation damage also destroys the spacecraft electronics
and sensors (the intensity of radiation in Jupiter's magnetosphere is
approximately 1 hellavalotta :-)

Galileo was designed on the 'One-Hoss Shay' principle.  Everything is designed
to last two years in Jovian orbit.

The RTGs decrease their output exponentially, so as the power drops, individual
instruments and subsystems can be turned off to maintain power to the rest of
the craft.  This is not the limiting factor on its lifetime.

        David Palmer
        [e-mail]
        ...rutgers!cit-vax!tybalt.caltech.edu!palmer
    "Direct quotes don't have to be exact, or even accurate.  Truth is as
    irrelevant to a newspaper as it is to a court of law"
    - Judge Alarcon, 9th circuit court of appeals (paraphrased)

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

Date: 5 Oct 89 14:21:25 GMT
From: wrksys.dec.com![e-mail]  (CUP/ASG, MLO5-2/G1 6A, 223-3283 05-Oct-1989 1016)
Subject: How the GALILEO mission may end.


        Regarding the GALILEO's mission end at Jupiter, the following
    excerpts are from Steve Willner's August 1989 edition of CANOPUS:

        GALILEO FINALLY GETTING "OFF THE GROUND" - can890815.txt - 8/21/89

        The exact pattern for GALILEO'S tour of the moons of Jupiter will
    not be decided until after launch since delays will affect the arrival
    date (a delay of a week will also eliminate the margin for the Gaspra
    asteroid encounter in 1991).

        The tour of the Jovian moons - primarily the Galilean moons - is
    to last about 20 months.  Options for an extended mission include
    cranking the orbit to higher inclinations to observe the polar regions
    or Jupiter, polar passes over the moons, or a "death plunge" into Io,
    the volcanic moon.

        Also:

        Officials said that no Shuttle retrieval mission will be attempted
    should the IUS fail to fire, stranding GALILEO as the European
    HIPPARCOS mission has been.  Retrieval is considered too hazardous,
    they said.

        Larry Klaes  [e-mail]
             or - ...!decwrl!wrksys.dec.com!klaes
                 or - [e-mail]
                     or - [e-mail]

        EJASA Editor, Astronomical Society of the Atlantic

             N = R*fgfpneflfifaL

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

Date: 5 Oct 89 16:38:26 GMT
From: rochester![e-mail]  (Brian Yamauchi)
Subject: Eye Surgery and Low Pressure (was Re: Astronaut Selection)

In article <[e-mail]> [e-mail] (Mary Shafer) writes:
>In article <[e-mail]> [e-mail] (Brian Yamauchi) writes:
>
>>Does NASA have any official policy on using eye surgery to meet vision
>>requirements?
>
>Yes.  The policy is _NO_.

>This policy will change if the FAA accepts RK, etc, but probably not
>immediately, based on what I've heard about the JSC flight surgeons.

>How would it look if someone had a RK, went into
>space, got exposed to reduced pressure, and blew their eyeballs out?
>(This reduced pressure scenario is, I understand, the explanation of
>the FAA's hesitancy on RKs.)

While this may be a problem with radial keritonomy, which reshapes the
eye through the use of incisions, it doesn't seem like it would be a
problem with the laser ablatement treatment which reshapes the eye by
vaporizing material from the surface of the cornea.

Can anyone who is more familiar with the medical details confirm or
deny this?

_______________________________________________________________________________

Brian Yamauchi                University of Rochester
[e-mail]        Computer Science Department
_______________________________________________________________________________

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

Date: 5 Oct 89 17:40:46 GMT
From: zephyr.ens.tek.com!orca!pooter![e-mail]  (Kendall Auel;685-2425;61-028;;pooter)
Subject: Re: How the GALILEO mission may end.

In article <[e-mail]> [e-mail] (CUP/ASG, MLO5-2/G1 6A, 223-3283  05-Oct-1989 1016) writes:
>
>        Regarding the GALILEO's mission end at Jupiter, the following
>    excerpts are from Steve Willner's August 1989 edition of CANOPUS:
>
>          [] or a "death plunge" into Io, the volcanic moon.

Oh, Great!!  Just go ahead and contaminate the pristine Io with
radioactive plutonium and Earth germs!!  Wait til I tell the
Christic Institute about THIS one. :-) :-)

Kendall Auel   [e-mail]

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

Date: 5 Oct 89 22:54:50 GMT
From: nic.MR.NET!ns![e-mail]  (John Logajan)
Subject: Re: Gravity Assist

<[e-mail]> [e-mail] (Kendall Auel) writes:
>What I'm seeing is that if I orbit a probe around a planet, then
>adjust the orbit so that the probe gets very close to the planet,
>it will accelerate and then just fly off into space.

I assume you are doing quantum time slice calculations.  I did the same
thing and saw the same results.  I believe it is simply that you are
accumulating errors in each calc, and the stronger the grave field, the
worse the error for each calculation.

--
- John M. Logajan @ Network Systems;  7600 Boone Ave; Brooklyn Park, MN 55428 -
- [e-mail], [e-mail], Phn 612-424-4888, Fax [phone] -

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

Date: 5 Oct 89 05:00:04 GMT
From: ibmpa![e-mail]  (nick szabo)
Subject: Re: What to do with the $30 billion (missions)

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] (nick szabo) writes:
>>
>>What projects, specifically, do you believe are fads, what is your evidence,
>>and why is this a bad thing?
>
>I'm not saying they're fads; I'm saying there is no overall plan, no
>unifying organization, and no attempt to be systematic.  Why no Venus
>mission in the list?  Surely not because there's nothing more to learn
>about Venus!

Venus is not on there because I, Nick Szabo, member of the
fallable (but improving) species Homo Sapiens, did not think to
put it on there.  Does that mean it should be off our Official Plan forever and
ever?  Now NASA, with its thousands of wise bureaucrats, doesn't deem
Venus _or_ Jupiter _or_ Mercury worth another visit, and
asteroids are only worth a breif flyby--unless the Station decides it needs
another easy billion, in which case there goes CRAF down the tubes, just
like NASP.


>Answer:  there's no Venus mission because it's not sexy
>or fashionable.  Come to think of it, I guess I *am* accusing the list
>of being fads.  The missions are chosen because they are hot topics of
>discussion right now,

'ARCF' is a hot topic of discussion?  I wish.  :-)

>>There is nothing to stop us from developing standard buses, like the Mariner
>>Mk. II (Galileo-class) or Obsever class, and mass producing these...
>
>Except that it won't be done.  There have been *several* attempts to do this
>already, all failures -- used for one or two missions and then discarded.

CRAF will be Galileo-class, and LGO (if approved) Observer-class.  Further
missions in each class would cost about $1.0 billion and $.8 billion,
respectively; less given reasonable economies of scale.

>
>The first thing that sticks out, when you start thinking about devising a
>plan rather than just a wishlist of missions, is that continuity of effort
>and hardware requires a steady flow of missions, and the current ones are
>just plain too expensive for that to happen.

Too expensive under the current political climate, in which NASA would
rather spend $30 billion for a mission to LEO than $1 billion for a
mission to an asteroid.

>
>>We could get some solid information about which parts of the solar system
>>are most promising for space settlement by the year 2000, if we got our
>>priorities straight.  As it stands now we will be living in ignorance for
>>some time to come.
>
>Ah, is *that* what the objective is supposed to be?  Then why aren't there
>more lunar and asteroid missions on your list?  Visiting *one* asteroid is
>*not* going to tell us whether the asteroids are better than the Moon.

Sigh.  To reiterate:

1) The list only included missions to be performed by the U.S., before the
year 2000, with funds formerly targetted towards the Space Station.
Non-U.S. missions, missions performed after 2000, and missions performed
with funding beyond Space Station level not included.

2) The main purpose of the list was to point out the gross inefficiency
inherent in the Station.  It was not meant to be a definitive Plan.  If you
don't agree with some of the details, fine, substitute your own wishlist
of missions, and see how they compare.

3) _One_ direct asteroid sample mission, _one_ asteroid flyby, a telescope
survey mapping the orbits and surface characteristics of all near-earth
asteroids, and asteroid sample-returns from Antartica.  Why are you griping
at me?  That's three more missions than NASA is willing to undertake.

4) The first space settlement may not be on either the Moon or an asteroid;
it may be on Mars, on a comet, on a Galilean moon, or out in free space
using resources from any of those.  "Moon or asteroids" is almost as narrow
as "Moon or Mars".

>If the objective is to determine the best locations for space settlement,
>then the list of missions should start with two or three lunar missions
>to settle major outstanding issues, plus half a dozen asteroid-rendezvous
>missions to *start* getting some idea of what that alternative looks like.

I certainly agree we should follow up our missions.  The near-earth asteroid
sky survey will give us some info, the Antartic samples will give us some
info, CRAF will give us some info, and then we can make wise choices on
where to send ARCF and its post-2000 (or non-NASA pre-2000) follow-ons.
I don't know why we're debating here, Henry.  Let's go knock down NASA's
doors!

>Plus a space station to start serious work on long-term microgravity effects
>and suchlike, which are also of some small importance to space settlement.

Oops.  I guess _this_ is what we are debating.  :-)
The Sovs already have more info on this than "Freedom" will ever get.
Ditto with LDEF, if it gets retrieved on time.

>(Before we start sending people out to spend their lives in space, it sure
>would be nice to know, for example, what a decade in 0.3G does to bone
>structure -- 0.3G is a lot easier than 1.0G for artificial gravity, and
>also happens to be the surface gravity of Mars.  I trust I need not point
>out that we can't examine decade-long effects by running ten times as
>many one-year experiments?  If we are to have *any* data on this by the
>year 2000, we need to get started *soon*.)

Of course, "Freedom" will only (re-) answer these questions for 0-g.
After we figure out that, say, Mars is a good place
to put a colony, we can put an LDEF there for two or three  years and get
almost all the info we need.  After that, somebody has to be first anyway, so
it might as well be the first group of miners.  There is no need for
manned missions that merely research the feasibility of manned missions.


"Get to know all the good properties."
        Donald Trump

--
--------------------------------------------
Nick Szabo
uunet!ibmsupt!szabonj
These opinions are not related to Big Blue's

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

Date: 5 Oct 89 18:17:20 GMT
From: zephyr.ens.tek.com!orca!pooter.WV.TEK.COM![e-mail]  (Kendall Auel)
Subject: Gravity Assist

The Galileo probe's trajectory to Jupiter got me thinking once again
about gravity assist and how it works.  What has been posted here
to the net explained that somehow a portion of the orbital energy
of a planet is transferred to the velocity of the probe.  I have
a copy of Taff's "Celestial Mechanics", but don't see any mention
of gravity assist in there.  I wrote a little simulation program,
but the math is not handled very well - there is lots of room
for error.

What I'm seeing is that if I orbit a probe around a planet, then
adjust the orbit so that the probe gets very close to the planet,
it will accelerate and then just fly off into space.  Am I seeing
a "real" effect, or just an artifact of mathematical errors?  Is
there a textbook which covers the topic of gravity assist?

I know, this is one of the top-ten most asked questions, but I
still don't have a very good concept of what's really going on here.

Thanks -

Kendall Auel   [e-mail]

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

Date: 5 Oct 89 16:04:09 GMT
From: gem.mps.ohio-state.edu!uakari.primate.wisc.edu!aplcen!stda.jhuapl.edu![e-mail]  (Jim Meritt)
Subject: Re: Astronaut Selection


Study Russian.    :-(


"In these matters the only certainty is that nothing is certain"
                    - Pliny the Elder
These were the opinions of :
[e-mail]  - or - [e-mail]  - or - meritt%aplvm.BITNET

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

End of SPACE Digest V10 #125
*******************