Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V09_2/V9_295.TXT

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Subject: SPACE Digest V9 #295

SPACE Digest                                      Volume 9 : Issue 295

Today's Topics:
          Re: 1992 moon base - Teleoperation
    Re: LANDSAT TO BE SHUT OFF SOON--PLEASE WRITE YOUR CONGRESSMAN
               Re: Babies born in space
              Re: Babies born in space.
            Here they go again...
          Re: 1992 moon base - Teleoperation
              Re: Babies born in space.
               Re: heavylift launchers
              Re: Babies born in space.
              Re: Babies born in space.
          Re: E'Prime and news about Thiokol
               Re: Lunar Robot?
----------------------------------------------------------------------

Date: Sat, 11 Mar 89 09:40:57 EST
From: Marvin Minsky <[e-mail]>
Subject:  Re: 1992 moon base - Teleoperation
To: [e-mail], [e-mail]

I agree with Paul Dietz about this:
    I don't think this proves anything, except that a 5-second
    delay means you cannot operate a Go-Kart at normal speed.
    Need I remind you that teleoperation of a lunar rover was
    accomplished years ago by the Soviets?

I met one of the Lunakhod drivers many years ago and he said it was
fun to drive.  Why are people so skeptical of telepresence when
successful control of systems involving delay are all around us?  I
think it is because of the myth that the mind makes direct contact
with the world through the body. Bad metaphysics makes bad
engineering.  Instead, one should consider a more realistic model of
how we interact with the world:

    The human sensory-processing-motor loop takes about T= 1/6 second.
    Therefore, with delay D, we can work at speed T/(D+T).

So, with 1 second delay, you should be able to work at 1/7 real time.

For an orbiting space station, with good communication, the delay
could be held to 2/3 second using geo relays, or to 1/6 second using a
chain of earth-based or LEO relays - so we could operate between 1/2
and 1/5 real time speeds.  There might be some special difficulties at
the 1/2 speed rate.  But I have seen no evidence that there are
difficulties at slower rates.

Such delays should be very tolerable, because the power and weight
requirements for a telerobot should be, I estimate, over 200 times
smaller than for a human.  If we also recognize that a person can work
attentively less than 1/4 time (6 hours/day), we have a payload gain
of over 800.  So, even with a slowdown of order 8, telepresence gains
us a productivity advantage of 100 per unit mass in orbit!
Accordingly, I believe that a telepresence-based space laboratory
could do the same or better at a much lower cost.  "Remotely-manned"
is better than either "manned" or "automated".

The telepresence equipment could surely be developed in 4 or 5 years,
because the engineering is not especially hard.  NASA should have done
it already, but it is never too late to start.

P.S    I propose the verb to "teep", for operating things by remote control.
    Teeping is fun and safe.

    Marvin Minsky

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

Date: 12 Mar 89 00:52:45 GMT
From: vsi1!v7fs1![e-mail]  (Mike Van Pelt)
Subject: Re: LANDSAT TO BE SHUT OFF SOON--PLEASE WRITE YOUR CONGRESSMAN

In article <[e-mail]> [e-mail] (Paul Dietz) writes:
>In article <[e-mail]> [e-mail] (Allan Pratt) writes:
>>Dan Quayle, of all people, seems to have found some money to keep
>>Landsat going.
>He got it from various government agencies that use Landsat data.  So
>some customers are willing to pay for its operation.

I just heard about that, and was going to post but y'all beat me to it.

I'll have to look up that newspaper item.  The way I heard it, Quale
dug up about $5M to keep Landsat going for another couple of months.
Congressman George Brown (D-CA) has written a letter to Bush urging
that Landsat be kept going.  The letter was co-signed by a bunch of
congressmen; it might not be a bad idea to (1) find out if your
congresscritter co-signed it, and (2) give him an "attaboy" if he did.

(Why "of all people"?  You don't believe everything the newsdroids
on TV tell you, do you?)
--
Mike Van Pelt                                 "Hey, hey, ho ho,
Video 7                                       Western culture's got to go."
...ames!vsi1!v7fs1!mvp                        Stanford students and faculty.

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

Date: Fri, 10 Mar 89 10:56:10 PST
From: Peter Scott <[e-mail]>
Subject: Re: Babies born in space

vsi1!v7fs1![e-mail]  (Mike Van Pelt) writes:

> I'm not sure rats have enough brains to figure out how to
>accomplish zero-G sex.

Who needs brains when you have natural selection? :-)

Peter Scott ([e-mail])

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

Date: 12 Mar 89 07:11:43 GMT
From: jarthur![e-mail]  (John H. Kim)
Subject: Re: Babies born in space.

This is my first posting so please excuse any botches :-)

I vaguely recall (sorry, don't remember where) a study that found out
that fetal development in bird eggs involved the cells at the bottom of
the undifferentiated cell mass *always* differentiated into the head (or
some other specific body part--I don't remember).  The obvious
conclusion would be that gravity provides a sort of compass for the same
types of cells (neural, muscular, etc) to aggregate in the same place.
I think the source went on to say something about babies conceived and
developed without gravity possibly ending up as just a mass of cells.

I think the next shuttle flight (or one forthcoming) involves an
experiment about this.

John H. Kim
[e-mail]
uunet!muddcs!jarthur!jokim

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

Date: 12 Mar 89 21:43:27 GMT
From: rochester![e-mail]  (Paul Dietz)
Subject: Here they go again...

I noticed an article in today's (3/12/89) NY Times about the shuttle.
The article comments on the tight schedule of launches this year due
to all the constraints from interplanetary launch windows, the decay
of LDEF's orbit, and delays so far.  The Dec. launch of HST is
described as "success oriented" (read: don't count on it).

The article observes that NASA is back to its old practice of
cannibalizing orbiters to get spare parts, a practice that the Rogers
commission explicitly criticized.  The MEC replacement for the current
launch came from Columbia.  Other examples were alluded to but not
decribed.  I guess buying an adequate supply of spare parts was just
too expensive.

    Paul F. Dietz
    [e-mail]

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

Date: 12 Mar 89 18:44:37 GMT
From: mist![e-mail]  (Ritchey Ruff)
Subject: Re: 1992 moon base - Teleoperation

In article <[e-mail]> [e-mail] (Marvin Minsky) writes:
>[...] NASA should have done
>it already, but it is never too late to start.

Well, some people at NASA Ames Human Factors are working on the hardware
for this.  Mike McGreevy and Scott Fisher have been working on a
"virtual workstation environment".  It includes 3D head mounted display
with motion and positional sensing, gloves that allow the computer to
track the hands (it's "shape"---finger positions---and its location)
and they are working on sound (so that as you walked around in the
virtual environment any sounds would seem to stay stationary).

They are also working in cooperation with JPL on a remote controlled
hand: you move your hand in the glove, and the robotic hand mimics
your action.

There was a Scientific American (10-87) that talks of this work.

They list possible applications like:
    - ad hoc repair and/or retrieval of GEO-sync satellites,
    - remote exploration of planets from orbit,
    - supervising automaticed robots.

>P.S    I propose the verb to "teep", for operating things by remote control.
>    Teeping is fun and safe.
>    Marvin Minsky

I always liked "waldo" (trivia: which sci-fi author came up with this term?).

--Ritchey Ruff            [e-mail]

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

Date: 13 Mar 89 00:42:58 GMT
From: silver![e-mail]  (Lucius Chiaraviglio)
Subject: Re: Babies born in space.

_

    This is actually in response to several of the recent sci.space
articles about embryonic development in zero gravity.

In article <[e-mail]> [e-mail] (John H. Kim) writes:
>I vaguely recall (sorry, don't remember where) a study that found out
>that fetal development in bird eggs involved the cells at the bottom of
>the undifferentiated cell mass *always* differentiated into the head (or
>some other specific body part--I don't remember).  The obvious
>conclusion would be that gravity provides a sort of compass for the same
>types of cells (neural, muscular, etc) to aggregate in the same place.
>I think the source went on to say something about babies conceived and
>developed without gravity possibly ending up as just a mass of cells.

    The problem with generalizing observations of birds, reptiles, and
amphibians to all vertebrates is that these vertebrates (and at least most if
not all fish) have very large yolky eggs whose cell division is distorted by
the yolk, which is itself influenced by gravity (it is heavier, so non-yolky
parts of the egg float over it.  Thus it makes sense that embryonic
development in these animals might evolve to take cues from gravity.  Effects
of gravity on Xenopus development have already been demonstrated, but of
course the effect of zero gravity has not been tested.  Thus, even this is
not necessarily an example of Xenopus (or its ancestors) having evolved
specifically to take a cue from gravity, but may just be an example of
development proceeding abnormally as a result of gravity in the wrong
direction.  Reason for suspecting the latter comes from the same experiments
showing the effects of gravity in the wrong direction, in which some of the
eggs are immune to these effects -- the immunity has been shown to be directly
correlated with rigidity of the cytoplasm of the eggs, which tends to prevent
the cytoplasm from being sheared out of alignment with the cortex (which is
what usually happens to eggs held at the wrong orientation).  I got this
information in personal communication with the principal investigators
performing these experiments and discovering the effect of cytoplasmic
rigidity:  Tony Neff and George Malacinski at Indiana University.  (This
information is also published, but I can't remember which journal it was
published in.)

    Even if the above-mentioned vertebrates do take actual developmental
cues from gravity, it is unlikely that mammals do so.  First of all, mammalian
eggs are very small (microscopic) and do not have much yolk, so forces of 1
gravity are unlikely to effect them unless they have a specific gravity
detection capability.  Even more important, it would be very detrimental for
mammalian embryos (other than those of monotremes such as platypuses) to
depend on gravity in order to develop properly, because they are carried
within their mother, which provides them with many advantages but also means
that it is impossible to guarantee a constant direction of gravity in any but
the largest mammals (and even these roll over occasionally) and impossible to
guarantee even a predominant direction of gravity in highly active mammals
such as tree-climbers and burrowing mammals.  Therefore it seems highly likely
that early mammalian embryonic development will be much affected by zero
gravity unless the physiological state of the mother is altered too much.

    The upshot of all this is that if you want to eat pork or beef in
space you need only have enough room to grow the animals (-: and some
appropriate device to alleviate the obvious problems that will develop in a
barn in zero-gravity :-), but if you want chicken or frog legs you are going
to have to import these items or bring a centrifuge.  8-)

--
|  Lucius Chiaraviglio   |  ARPA:  [e-mail]
BITNET:  [e-mail] (IUBACS hoses From: fields; INCLUDE RET ADDR)
ARPA-gatewayed BITNET:      [e-mail]
Alt ARPA-gatewayed BITNET:  [e-mail]

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

Date: 11 Mar 89 21:45:57 GMT
From: attcan!utzoo![e-mail]  (Henry Spencer)
Subject: Re: heavylift launchers

In article <[e-mail]> [e-mail] writes:
>    I'm still missing something - why not start cranking out Saturn V's
>again? Would it be as difficult as building a new launcher? ...

No, but it's not orders of magnitude easier, either.  A substantial amount
of the engineering would have to be re-done, especially the development
and testing of the engines.  The Boeing/Hughes "Jarvis" study very badly
wanted to use Saturn V engines rather than Shuttle engines, but eventually
had to give up on the idea.  "When we dropped it, it broke."

Don't forget that all the launch facilities have been rebuilt for the
Shuttle, too.

>... Are the designs for the Saturn available to space companies?

I imagine so.  What's lacking is the capital to do anything about it.
It would cost a lot, and there are no guaranteed customers.
--
Welcome to Mars!  Your         |     Henry Spencer at U of Toronto Zoology
passport and visa, comrade?    | uunet!attcan!utzoo!henry [e-mail]

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

Date: 13 Mar 89 00:47:18 GMT
From: amara![e-mail]  (S. Khai Mong)
Subject: Re: Babies born in space.

What about the position of the fetus in the womb?  And the orientation of
the baby during delivery?  Surely gravity factors into these.
--
Sao Khai Mong:   Applied Dynamics, 3800 Stone School Road, Ann Arbor, Mi48108
[phone] (uunet|sharkey)!amara!khai  [e-mail]

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

Date: 13 Mar 89 05:23:32 GMT
From: texbell!nuchat![e-mail]  (Elizabeth Nuchia)
Subject: Re: Babies born in space.

In article <[e-mail]> [e-mail] writes:
>    I saw a report recently that had a Get-Away-Special mission that was
>sending up half of a set of ``identical'' chicken eggs, the other half staying
>on the ground as a control group. While not exactly human development, I'd
>say it's certainly a first step in such research.

I believe that this experiment is a student experiment and will be flying
in the crew cabin middeck area.  Get-Away-Specials are not necessarily
student experiments and are flown in cannisters located in the payload bay.

The sponsor of the chicken egg experiment is Kentucky Fried Chicken.  It was
originally manifested on 51-L, this one is a replacement.
--

Elizabeth Nuchia      Lockheed Engineering Sciences Company
uunet!nuchat!eliz     2400 NASA Rd. 1,  Houston, Texas  77258
[phone]          I don't speak for Lockheed or NASA, and vice versa.

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

Reply-To: mordor!rutgers!pnet01.cts.com![e-mail]
Date: Thu, 9 Mar 89 08:20:56 PST
From: mordor!rutgers!pnet01.cts.com![e-mail] (Jim Bowery)
To: ucsd!nosc!crash![e-mail]
Subject: Re: E'Prime and news about Thiokol

Bob Pendleton writes:
> ... What do you mean by "MX booster segment?"
> The MX is a 3 stage booster, none of the stages are segmented.

The configuration table I gave was incorrect.  Bob is correct that the
MX is a 3 stage configuration.

E'Prime (after talking directly to a company representative) is
using the first 2 stages of the MX configuration exactly as currently
manufactured.  The third stage will be contract/mission specific.

The strap-ons will be the same as the first stage.

I'm curious as to how E'Prime gets away with saying that out of 17 test
flights none have failed when Bob claims that the MX booster produced by
Thiokol has killed several people.  Were the ground tests a disaster followed
up by a streak of good luck?  What sort of quality controls were imposed by
Thiokol on the flight-bound boosters to make them so reliable?  What
additional safety measures were imposed by the Air Force?  Since a decent
solid rocket inspection system costs a small fraction of a launch (only about
$2million amortized over many launches) I would guess E'Prime could afford
to put all Thiokol's boosters through their own inspections.
---------------------------------------------------------------------------
Jim Bowery    Phone: [phone]
PO Box 1981                  Join the Mark Hopkins Society!
La Jolla, CA 92038   (A member of the Mark Hopkins family of organizations.)

UUCP: {cbosgd, hplabs!hp-sdd, sdcsvax, nosc}!crash!pnet01!jim
ARPA: crash!pnet01![e-mail]
INET: [e-mail]

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

Date: 13 Mar 89 16:47:35 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Lunar Robot?

In article <191700020@trsvax> [e-mail] writes:
>There is an article in the March 5th EE Times about a radio astronomy
>observatory on the moon that will be erected and maintained by a robot
>vehicle...
>Does anyone out there have any idea on the likelyhood of this coming to pass?

It's just another design study.  Probability near zero in the current climate.
--
Welcome to Mars!  Your         |     Henry Spencer at U of Toronto Zoology
passport and visa, comrade?    | uunet!attcan!utzoo!henry [e-mail]

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

End of SPACE Digest V9 #295
*******************