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Subject: SPACE Digest V12 #474

SPACE Digest                                     Volume 12 : Issue 474

Today's Topics:
             Re: Theories needed on life
             planetary longitudes
             Re: Theories needed on life
            Voyager/Triton Article
          Re: more talk about space stations
                  Re: Names
              Galileo Update - 10/19/90

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

Date: 20 Oct 90 07:35:12 GMT
From: agate!shelby!helens!hanauma![e-mail]  (Joe Dellinger)
Subject: Re: Theories needed on life

In article <[e-mail]> [e-mail] (Bruce Worden) writes:
>I am under the impression that there are relatively few ways for organisms
>to adapt to a given environment.  An often cited example is the physical
>characteristics of desert plants some of which appear nearly identical to
>plants on another continent even though the two are completely different
>species.

You might want to read "Wonderful Life" by Stephen J Gould. Basically he
paints a picture of evolution having a large random component. Species
diversify for a while, and then WHAM, something comes along and randomly
wipes out entire branches of the evolutionary tree. The survivors diversify
again, but some of the diversity is well and truly lost forever.

All the animals we normally think of, things like lizards, bears, dogs, whales,
horses, people, monkeys, snakes etc, are variations on a remarkably consistent
theme. A backbone with vertebrae, 4 limbs, five digits per limb, one head,
one tail, etc etc. Sure there are some variations: snakes suppressed all the
limbs, whales two of them. People have modified two limbs for manipulation,
and suppressed the tail. Giraffes have greatly lengthened some of the
vertebrae. Horses have suppressed all but 1 digit on each limb. Etc, etc.
But the basic body plan is the same. This basic plan has been around a long
time now, and the originator of it was probably like nothing alive today.
It's just far faster for evolution to keep ringing variations on the old
themes as needed than it is to invent something new from scratch. New
inventions don't stand a chance competing against the old established
monopolies.

That's not to say that some traits or organs can't get invented again and
again: how many times have eyes evolved independently? Your eyes and
horses' eyes and whales' eyes and fishes' eyes are all under the same patent,
as it were. We all inherited our eyes from our common vertebrate ancestor.
However the Octopus, an invertebrate, evolved its eyes independently. And
even though Octopus eyes LOOK pretty much like ours their independent origin
shows: many of the internal details are quite different.

On the other hand, it didn't have to go that way. Insects evolved something
completely different for eyes. Some molluscs even evolved reflecting telescopes
for eyes instead of refractors like ours, I've read.

So my guess is that IF the basic body plan that gets established early on
happens to have 4 limbs, a head, and a tail, you MIGHT end up with something
very human-looking in appearance at some point. But there's no reason to expect
that basic body plan will win the lottery very often. And even if you got
something that looked human the details would probably be different. The human
food and air tubes stupidly have to CROSS each other to get to the lungs and
stomach. Rather silly design; how many times have you nearly choked? Human eyes
strangely put the detector layer BEHIND the layer that feeds the detector
layer. Stupid design; we have to look through all that junk. Octopus eyes got
lucky and evolved it the other way around.

One last point: by some standards we aren't even all that successful. Where
are all the species closely related to us? We're the only species left in
our genera! And the few reasonably close relatives we still have, Gorillas
and Chimpanzees, are only just hanging on. Lucky for us we figured out
these tool-using and speech tricks, and managed to pull it out pretty well
these last few ten thousand years. Of course, ten thousand years is NOTHING...
come back in a few million years and see how we're doing. Probably we'll
either have colonized the local group by then, or we'll be extinct. Anybody
want to make a bet?
\    /\    /\    /\/\/\/\/\/\/\.-.-.-.-.......___________
 \  /  \  /  \  /Dept of Geophysics, Stanford University \/\/\.-.-....___
  \/    \/    \/Joe Dellinger [e-mail]  apple!hanauma!joe\/\.-._
** tick ****** tick **** tick! *** tick! ** tick! tick! tick! RING! **** WHAM **

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

Date: 19 Oct 90 13:59:39 GMT
From: ubc-cs!news-server.csri.toronto.edu!utgpu!watserv1!ria!uwovax![e-mail]
Subject: planetary longitudes

Several comments on recent postings:

     Longitude measurement on any world, Earth included, is purely arbit-
rary. There are really two basic approaches: on any body in synchronous
rotation around another, the prime meridian used by cartographers is that
which faces the primary (i.e. on the Moon it is the mean position of the
sub-Earth point, on Phobos the mean position of the sub-Mars point and so
on). For objects not in synchronous rotation the choice is more arbitrary,
and the prime meridian's position is determined simply by calculating the
number of rotations since some standard time at which the prime meridian
was pointing in a specified direction. However, these 'dynamic' definitions
are not reliable unless we know the rotation state and librations very well
indeed. So, for cartographic purposes it is better to identify some very
small but clearly definable point such as the centre of a small circular
crater, and making that the 'Greenwich' of the planet. This is done whenever
suitable images are available. This 'Greenwich' might not be on the prime
meridian if that region (according to the original dynamic definition) has
not been photographed yet.

Examples:

Mercury      - crater HUN KAL defines  20 deg. long.
Venus        - crater Ariadna defines   0 deg. long.
Mars         - crater Airy-0  defines   0 deg. long.
Ganymede     - crater Anat    defines 128 deg. long.

     For more detail, see a paper by M.E. Davies and others in the journal
CELESTIAL MECHANICS, Vol. 39, 1986. Revisions are no doubt on the way.



Phil Stooke,
Department of Geography,
University of Western Ontario,
London, Ontario, Canada N6A 5C2

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

Date: 19 Oct 90 20:35:03 GMT
From: munnari.oz.au!uhccux!hale![e-mail]  (Alan Whinery)
Subject: Re: Theories needed on life

In article <[e-mail]> [e-mail] writes:
>Could someone theorize on what humanoid life would be like on a planet 3 or 4
>times the size of the Earth.  I'm looking for theories on body structure,
>societies, technology, psychology, etc.  Thanks, I appreciate any speculation.
>
>                    dml
This isn't going to be another one of THOSE questions, is it?

I postulate : If a planet were 3 to 4 time the size (let's say radius) of the
earth with similar density, it would not be a very nice place for any
thing resembling humanoids.

Since a factor of 4 in the radius would increase the surface area by a factor
of 16 and the volume (and thus the mass at a specific density ) by a factor
of 64!

I suppose the questions at hand are, does your theoretical planet need to be
all THAT big? And -- do the creatures need to be humanoid? If you lowered the
density considerably so that the creatures could move around a little,
maybe a mini gas giant -- a Gas Midget!  All of this raises a question
of planetary stability, of course...

Alan the night Janitor
The Institute for Astronomy
Somewhere in the central Pacific
_constantly reading Asimov's non-fiction_
[e-mail]

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

Date: 19 Oct 90 22:22:29 GMT
From: swrinde!zaphod.mps.ohio-state.edu!sdd.hp.com!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Voyager/Triton Article

Associated Press -- 10/18/90
"Voyager-Triton"
By Lee Siegel

"Five-mile-tall black plumes that look like volcanic geysers
erupting on Neptune's moon Triton really may be swirling
funnels of dust, gas and nitrogen ice, some Voyager 2
spacecraft scientists now believe."

The AP's Los Angeles science writer reports that California
Institute of Technology and Voyager scientist Andrew
Ingersoll argues in today's issue of the journal Science that the
plumes are really dust devils, just the same as similar
occurrences on Earth and Mars.

The report quotes Ingersoll as saying "the majority theory is
still that they're geysers.  But we're having a live debate."  The
story further states that the debate won't be settled until
further analysis of the Voyager 2 data allows an
understanding of Triton's atmospheric temperature as it
relates to altitude.

The story states that if the temperatures in Triton's
atmosphere are colder at higher altitudes, as they are on
Earth, the slightly warmer icy fog in geysers could float
upward.  But preliminary evidence, according to the report,
suggests the opposite -- which further suggests there might be
warm bare spots on the moon's surface.

According to the AP, Ingersoll and colleagues at CalTech
argue that bare spots on Triton's surface would be conducive to
dust devils, which theory Ingersoll says is further supported by
the fact that the plumes remain constricted in diameter as they
rise, exactly like dust devils do elsewhere in the solar system.

The report cites Ingersoll's remark that dust devils on Earth
rise some 2,000 feet, on Mars they rise nearly four miles and
could rise even further on Triton.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|
     | | | |  __ \ /| | | |      Ron Baalke         | [e-mail]
  ___| | | | |__) |/  | | |___   Jet Propulsion Lab | [e-mail]
 /___| | | |  ___/    | |/__ /|  M/S 301-355        |
 |_____|/  |_|/       |_____|/   Pasadena, CA 91109 |

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

Date: 19 Oct 90 03:24:32 GMT
From: news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: more talk about space stations

In article <[e-mail]> [e-mail] writes:
>   Last, and this one has been touched on before (but I missed the answer),
>what is the problem with simply adding logistics/support to a new shuttle
>that has the entire cargo bay as a lab (as opposed to retrofitting with
>spacelab) and blasting the sucker permenantly into orbit?

The orbiter systems are not built for long stays in space, or for
maintenance and resupply in orbit (with a few exceptions).  You'd
have to revise many things.  You'd also have to build *something* to go
in the cargo bay, since the orbiter has to open its bay doors in orbit
(the heat radiators are on the inside of the doors) and in any case
the cargo bay is not built to hold pressure.  What you will end up
doing is building all the bits and pieces of something like SII's
Industrial Space Facility or a Spacelab-based station, and there will
be little point to leaving an orbiter wrapped around it.
--
The type syntax for C is essentially   | Henry Spencer at U of Toronto Zoology
unparsable.             --Rob Pike     |  [e-mail]   utzoo!henry

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

Date: Fri, 19 Oct 90 22:15:06 EDT
From: John Roberts <[e-mail]>
Disclaimer: Opinions expressed are those of the sender
    and do not reflect NIST policy or agreement.
Subject: Re: Names


>From: sdd.hp.com!wuarchive!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!watserv1!ria!uwovax![e-mail]
>Subject: planetary north and names

First of all, let me point out that Phil is describing things as they *are*,
while I am presenting a viewpint of how I think things *should* be.
There doesn't seem to be any rule against occasional griping on the
net. :-)

>Latin names on planets are useful when dealing with an international
>community of scientists. How can we use 'vernacular' names like 'Mariner
>valleys' in an international setting without being offensive?

By providing translations.

I think the chief advantage of Latin feature names is that I can read a
paper by an astronomer from Finland, written in his/her native language,
and instead of being unable to understand a single word, I'll be able
to pick out the place names, and nothing else. I suppose it's silly of me to
think that feature descriptions could be translated along with the rest of
the paper.

>Look at
>medical terminology for all those squishy things inside us, or the latin
>names of genera and species of living things - latin is not really a dead
>language in science after all.

Maybe someday there will be a philological horror movie: "Night of the
Living Dead Language". In the movie, a ponderous, decrepit creature dressed
in tattered rags will grab screaming high school coeds and suck the blood
from their brains, causing them to flunk out of science and become
cosmetologists.

>Besides, it is just as easy to learn words
>like 'tessera' or 'tholus' as simple terms like 'graben' or 'caldera',
>without thinking of them as words in a foreign language.

But they *are* foreign words. Unlike many terms of Greek and Latin
origin that have become "anglicized" over the centuries, these words
require Latin rules for plurals and other manipulations. What would be
the Latin equivalent of the transition from "crater" to "craterization"?
While I would like someday to learn Latin for its own sake, I don't
much appreciate being forced to pick up so much to follow astronomy, and
I suspect it's a total turn-off to many members of the general public
who might otherwise become enthusiasts and proponents of astronomy.

>Incidentally, on a planetary subject, I have just received the new soviet
>atlas of Venus (ATLAS POVERKHNOSTY VENERY) from Sojuzkarta.
>... The text portion is only in russian
>but a gazetteer at the end lives latin equivalents.

That's another problem - the character set has changed over the milennia.
The English alphabet has several significant differences. Cyrillic
is completely different at least in appearance, and Japanese has no
relation whatsoever.

>Phil Stooke,
>Department of Geography,
>University of Western Ontario,
>London, Ontario, Canada N6A 5C2
             John Roberts               (lingua somewhat in cheek)
             [e-mail]

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

Date: 19 Oct 90 18:34:42 GMT
From: sdd.hp.com!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Galileo Update - 10/19/90


                          GALILEO STATUS REPORT
                            October 19, 1990

     Yesterday was the first anniversary of the Galileo launch from STS-34.
Spacecraft performance and health are excellent; plans for the Earth flyby
activities on December 8 are proceeding well.

     As of noon (PDT) Thursday, October 18, 1990, the Galileo spacecraft is
27,913,650 miles from the Earth and traveling at a heliocentric speed of
54,110 miles per hour; distance to the Sun is 111,233,990 miles (1.21 AU).
Round trip light time is 5 minutes, 4 seconds.

     A NO-OP command was sent on October 15 to reset the Command Loss Timer
to 264 hours, the planned value for this mission phase.

     A series of Delayed Action Commands (DACs) were sent to the spacecraft on
October 16.  The first DAC reconfigured the downlink telemetry data rate from
1200 bps, which was automatically selected by the stored sequence, to 40 bps
(uncoded) to enable positive verification of subsequent DACs.  The data rate
change was necessitated by a recent DSN (Deep Space Network) coverage change
which provided the 70-meter station to Ulysses for its TCM (Trajectory
Correction Maneuver) resulting in Galileo using the 34-meter station in
Australia.

     As a further consequence of Ulysses related coverage changes, the planned
delta DOR (Differential One-way Ranging) on October 16 was moved to October 17
requiring DACs to reconfigure the radio frequency subsystem and the Telemetry
Modulation Unit for the delta DOR activity and then reconfiguring the hardware
back to normal operating state.

     The last DACs sent on October 16 involved powering off the NIMS (Near
Infrared Mapping Spectrometer) electrical heater to preclude a possible
thermal violation of the SSI (Solid State Imaging) detector limit resulting
from positioning the scan platform at large cone angles (above 165 degrees).
The high cone angle positions were required to support UVS (Ultraviolet
Spectrometer) Lyman Alpha data collection on October 18.  Subsequent to the
Lyman-Alpha activity, the NIMS heater was reactivated.  Since the heater was
powered off for a short time (about 3 hours) there was minimal effect to the
thermal control of the RPM (Retro Propulsion Module).

     The EUV (Extreme Ultraviolet Spectromter), DDS (Dust Detector) and MAG
(Magnetometer) Cruise Memory Readouts (MROs) planned for October 16 were
commanded via the stored sequence but about a 95 percent of the data was lost
due to Australia 70 meter coverage provided to Ulysses; however, the cruise
science MROs on October 18 were successfully performed and collected.

    A Command Detector Unit (CDU) Signal-to-Ratio (SNR) test was successfully
completed on October 16.  This periodic test provides continuing trend
information characterizing the telecommunications hardware used for uplink
commanding.

     Another delta DOR activity was successfully completed on October 17.
This activity again was a North/South pass using the 70 meter antennas in
Australia and Goldstone.  This was the seventh of 27 planned delta DOR
activities prior to Earth closest approach.  Delta DOR is an additional
navigation data source in addition to doppler and ranging data.

     The VE-9 (Venus-Earth-9) Part I memory sequence load was successfully
transmitted and received by the spacecraft on October 18.  This sequence
controls spacecraft activities from October 22 to December 7 and includes
time windows for TCM-7, TCM-8, TCM-8A, the PLS (Plasma Instrument) shade
retraction, Probe Checkout, and the playback of Venus data activities.
Part II of the VE-9 sequence memory load was successfully transmitted and
received by the spacecraft today.  The entire VE-9 sequence memory load is
now on-board Galileo and will become active on October 22.

     UVS Lyman Alpha data collection continued as planned on October 18.
This data is stored on the spacecraft tape recorder for playback along with
Venus Encounter data planned for November 19-21.

     The AC/DC bus imbalance measurements exhibited some minor activity.
The AC measurement fluctuated 1 to 2 DN during a period of no spacecraft
activity and is stable near 48.6 volts.  The DC measurement dropped about
10DN and is stable near 18.8 volts. All other power-related and subsystem
telemetry measurements are normal.

     Sometime between the end of the DSN track on October 17 and the start of
track on October 18, the ninth despun CDS (Command Data Subsystem) Critical
Controller 2A POR (Power on Reset) telemetry indication was observed.  The
signature was the same as that observed in the previous eight occurrences.
Actions to reset the telemetry indication were completed later on October 18.
All actions were successfully completed and a NO-OP command was sent to reset
the Command Loss Timer to 216 hours, the planned value for this mission phase.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|
     | | | |  __ \ /| | | |      Ron Baalke         | [e-mail]
  ___| | | | |__) |/  | | |___   Jet Propulsion Lab | [e-mail]
 /___| | | |  ___/    | |/__ /|  M/S 301-355        |
 |_____|/  |_|/       |_____|/   Pasadena, CA 91109 |

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

End of SPACE Digest V12 #474
*******************