Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT_ZIP/spacedig/V15_0/V15NO025.ZIP/V15NO025

Internet Message Format | 1993-07-13 | 29KB

Date: Thu, 23 Jul 92 05:00:01
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #025
To: Space Digest Readers
Precedence: bulk


Space Digest                Thu, 23 Jul 92       Volume 15 : Issue 025

Today's Topics:
              2nd (last)  RFD sci.space.planets (2 msgs)
              Answers to PLANES of the ecliptic question
                        antimatter explosions
        Antiproton-Boosted Microfission (was: Antimatter ...)
                              ESA Future
                   first man on moon date and time
                      Galileo Update - 07/22/92
Magellan successors? (was Re: Support Lunar Resource Mapper Too!) (5 msgs)
                    Propulsion questions (2 msgs)
           Testers for Astronomy Lab: NEW E-MAIL ADDRESS!!!
                         U.S. Black Programs
                 UFO-pic from Phobos2-probe posted !
                        Visual acuity (2 msgs)
                    Visual acuity in microgravity
                                Whales
                         Whales and dolphins

    Welcome to the Space Digest!!  Please send your messages to
    "[e-mail]", and (un)subscription requests of the form
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    (THENET), or [e-mail] (Internet).
----------------------------------------------------------------------

Date: 22 Jul 92 15:13:05 GMT
From: "Richard H. Miller" <[e-mail]>
Subject: 2nd (last)  RFD sci.space.planets
Newsgroups: sci.space,news.groups,sci.astro

In article <[e-mail]>, [e-mail] (David Knapp) writes:
>
> One thing that almost all posters ignored was that one of my main
> reasons for suggesting a new group would be to *stimulate* planetological
> discussion, not solely to move traffic around.  Cross posting is always
> (unfortuntely) an option.  Right now, wading through a bunch of
> vague subject lines in sci.astro that may or may not have interesting
> planetary contexts is time consuming and unenlightening.  With a group
> devoted just to planetary issues, we could all just read that group!

This is never a good reason for forming a group. The presence of a newsgroup
will almost never generate discussion. In general, newsgroups follow rather
than lead topics. If you want to stimulate the discussion, the normal was is
to either

    1) Start topics threads in existing news groups and when you have
           enough traffic. spawn your new newsgroup off.

    2) Start a mailing list; When you have enough people [around 100] then
           you can form a news group.

The idea that a newsgroup will generate posting has resulted in several low
usage news groups such as comp.edu.composition,comp.internet.library,
comp.lang.idl-pvwave,comp.lang.sigplan,comp.org.issnnet and  sci.comp-aided.
Let's not create another one



--
Richard H. Miller                 Email: [e-mail]
Asst. Dir. for Technical Support  Voice: [phone]
Baylor College of Medicine        US Mail: One Baylor Plaza, 302H
                                           Houston, Texas 77030

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

Date: 22 Jul 92 15:36:02 GMT
From: Ilana Stern <[e-mail]>
Subject: 2nd (last)  RFD sci.space.planets
Newsgroups: sci.space,news.groups,sci.astro

I would just like to point out that David Knapp appears to have either
gotten me confused with someone else (partially) or mis-edited an article
I followed up, as he has credited me with a few words I did not write.
His quotes of my email and articles are basically correct, except I
did not say:

>"...I agreed to withdraw my objection
>if (1) an effort be made to allow access by non-Usenet people (comparable to
>SPACE Digest), and (2) Earth be excluded from discussions involving politically
>hot topics like ozone depletion and global warming, not because these topics
>are unworthy, but so this won't become yet another fiery political group."

He has correctly stated my basic position (that I would only support
sci.space.planets if it would not duplicate sci.geo.meteorology).

--
/\        Ilana Stern DoD#009 | Whoever first said, "Things are seldom as they
  \_][    [e-mail] | seem," was wrong.  Things are usually as they
      \_______________________| seem.  Otherwise, they wouldn't seem that way.

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

Date: Wed, 22 Jul 1992 10:01:58 GMT
From: Hartmut Frommert <[e-mail]>
Subject: Answers to PLANES of the ecliptic question
Newsgroups: sci.space,sci.astro

I wrote:

>The galactic North Pole is at
>
>L=0.018      B=-29.81   degrees in Solar System Main Plain coord's.

>[ calculated from
>   Solar System North P: R.A.= 18 h 00 m = 270.00 deg, Dec = + 66.55 deg
>   Galactic North Pole:  R.A.=  0 h 49 m =  12.25 deg, Dec = - 27.40 deg ]

I took J2000 coord's if I rem' right (now I took from my 1986 MS thesis).

>This implies an *inclination* of

>i_g = 119.81 degrees

>(and a node Omega_g = 90.018 degrees). So the inclination of both axes/
>equators is approx. 60 degree, the direction of rotation is opposite.

[..]

>-----------
>From: Bill Gawne, Space Telescope Science Institute

>The galactic north pole (J1950 coordinates) is at
>right ascention 12 h 49 m, declination 27 degrees 4 minutes.

which is my galactic SOUTH pole to good approximation. Look at the direction
of rotation (right hand rule..).

[..]

Hope this clears.
--
 Hartmut Frommert, LS Dehnen, Physics, | E-Mail: <[e-mail]>
 Univ of Constance, P.O.Box 55 60,     |     or  <[e-mail]>
 D-W-7750 Constance, Germany  | + SAVE THE WHALES ! BOYCOTT NORWAY !        +
 Phone: [phone]   | + Whales R intelligent. Whale killers not.  +
+ Whale killing is murder. Eating whales is cannibalism. Eat whale killers. +

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

Date: Wed, 22 Jul 92 16:43:13 BST
From: [e-mail]
Subject: antimatter explosions

According to Dr. Forward, antimatter explosions of small quantities
are not a big problem.

Anti-matter doesn't make a good bomb because it doesn't really
detonate. It blows itself into a cloud that annihilates over too
large a space and time to cause damage commenserate with its' energy
density. ie, it is a big fizzle.

Also, it is fairly clean because there are not lots of heavy
nucleotides created. So you get a slow flash with a nasty dose of
line of site gammas. The neutrinos flash off into the universe and
not much else happens. If you are close enough to get hit by the
muons,etc you are probably close enough that the muons were the least
of your worries...

As to the Kg on the farside: It probably would not be quite the
damaging GT explosion you are imagining. It would blow itself and the
plant to kingdom come, but it would still be reacting as peices went
upwards. Since the moon is surrounded in vacuum, I would guess that a
great deal of it would not even annihilate at all, unless it went
suborbital. If that were the case, we could follow the bouncing
antimatter fragments...



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

Date: 22 Jul 92 13:05:55 GMT
From: Blake Philip Wood <[e-mail]>
Subject: Antiproton-Boosted Microfission (was: Antimatter ...)
Newsgroups: sci.space

All the postings so far have missed the most realistic application of
antimatter to space propulsion:  antiproton-boosted microfission.
This is being investigated by a number of folks at Penn State, in
collaboration with some people at Phillips Lab in Albuquerque.
The Penn State lead is R.A. Lewis.  The reference I happen to have
on hand is from Nuclear Science and Engineering, (109) p.411 (1991).

The basic idea is that hitting a U235 or Plutonium nucleus with an
antiproton makes it so unstable that you get an average of 16 neutrons
out of the resulting fission, as opposed to the usual 2-3.  This means
that the critical mass which can be completely fissioned is very
small.  The paper I referenced above discusses using an ICF
arrangement to compress a Plutonium pellet, then irradiate it with
antiprotons at peak compression.  The advantage of this approach
is that you can do it with quantities of antimatter which can be
produced today in large accelerators.  The article above quotes
results from another paper which suggests that fissioning one
70mg Plutonium pellet per second in this fashion, each event requiring
only 2e8 antiprotons, could yield 5GW of power in a complete propulsion
system with a specific mass of only 0.07 kg/kW.

--
                 Blake P. Wood - [e-mail] [phone]
                 Group P-1, MS-E526, LANL, Los Alamos, NM  87545

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

Date: 22 Jul 92 14:04:12 GMT
From: Matthew DeLuca <[e-mail]>
Subject: ESA Future
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:

>Should look up terms like "in kind" aid. And "cheaper facilities." And
>"hypersonic wind tunnels."  And other goodies which could be rented at cost.

This is probably the best bet for cooperation between Russia and the ESA,
but there is going to be a *very* strong domestic lobby for keeping jobs
of this nature within the host countries, and not shipping them off to Russia,
no matter how much money is saved.  If you think U.S. labor interests are
bad, you should look at Europe...
--
Matthew DeLuca                      "I'd hire the Dorsai, if I knew their
Georgia Institute of Technology      P.O. box."
Office of Information Technology                - Zebediah Carter,
Internet: [e-mail]              _The Number of the Beast_

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

Date: 22 Jul 92 16:08:38 GMT
From: Henry Spencer <[e-mail]>
Subject: first man on moon date and time
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:
>at what time the first man stepped on the moon and when it wass
>televised...

2256 EDT 20 July 1969.  The TV coverage was live (well, subject to the
speed-of-light lag...).
--
There is nothing wrong with making      | Henry Spencer @ U of Toronto Zoology
mistakes, but... make *new* ones. -D.Sim|  [e-mail]  utzoo!henry

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

Date: 23 Jul 92 00:22:13 GMT
From: Ron Baalke <[e-mail]>
Subject: Galileo Update - 07/22/92
Newsgroups: sci.space,sci.astro

Forwarded from:
PUBLIC INFORMATION OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109.  TELEPHONE [phone]


                     GALILEO MISSION STATUS
                          July 22, 1992

     The Galileo spacecraft is more than 204 million kilometers
(about 127 million miles) from Earth, and some 269 million
kilometers from the Sun; its speed in orbit is 20,651 meters per
second or 46,194 miles per hour.  The spacecraft has flown about
2.13 billion kilometers (1.32 billion miles) since launch.

     This week Galileo is conducting exploratory activities with
the high-gain antenna deployment motors and retracting its rear-
view low-gain antenna.  On Monday, the flight team sent the mini-
sequence for these operations to the spacecraft.

     Tuesday, the spacecraft turned to a warming attitude (31
degrees off the Sun) and turned on the antenna-deploy motors for
less than 2 seconds, and today, Wednesday, the motors are being
turned on for another 2 seconds after 24 hours of warming.  (The
first deploy-motor pulse was done April 29, when the antenna
tower region was somewhat cooler).

     Thursday, July 23, the spacecraft's second low-gain antenna,
which pivots down on a long mast from one of the RTG booms, will
be driven back up to its stowed position.  This action will exert
small forces on the spacecraft, which will be measured using the
spacecraft gyros.

     Engineering telemetry for these events will be captured on
the spacecraft tape recorder and played back each day.  The
engineers believe these activities may provide a better under-
standing of the antenna situation to support future action.

                              #####
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Most of the things you
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | worry about will never
|_____|/  |_|/       |_____|/                     | happen.

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

Date: 22 Jul 92 10:13:20 GMT
From: Bill Higgins-- Beam Jockey <[e-mail]>
Subject: Magellan successors? (was Re: Support Lunar Resource Mapper Too!)
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Hartmut Frommert) writes:
> [e-mail] writes:
>>Support Lunar Resource Mapper as well [...]
>>Do you know that after Mars Observer's mission is over, that we will
>>know more about Mars and Venus than about the Moon! That is tragic and
>>must be corrected.

> On the other hand, that our knowledge on the Moon needs improvement, and,
> therefore, LRM, should in *NO* way mislead anybody to think that we know
> *ALL* interesting things (or even too much) on Mars and/or Venus. So also a
> successor of Magellan, as well as Mars Observer (and LRM) should be taken
> into consideration.

I asked Dr. Gordon Pettengill this question last year: "Is there a
successor to Magellan?"  The answer is no.  Magellan is giving such a
stupefying quantity of radar mapping data that it will take decades to
sort it out, and no system giving, say, higher spatial resolution is
currently planned.

Venus orbiters and landers have given a pretty good view of the
planet.  I suppose having an orbiter in place to give long-term
information about the atmosphere and magnetosphere would be a good
idea-- Pioneer Venus Orbiter is about to die.   The U.S. program is
not ready to build landers, and the Russian program has put the planet
on the back burner in favor of long-neglected Mars. A Venus rover
would be neat, but a rather tough engineering challenge.  Maybe more
balloons?  Anyway, I think you're going to see a long hiatus in Venus
exploration.

Flying a Magellan-type mission to Mars or the Moon would be neat, too,
but synthetic-aperture radar demands a heavy committment of
tracking-network resources.  It was the *only* way to get maps of the
Venerian surface; since optical methods work well on other bodies,
it's much less urgent to try SAR.  Titan is an obvious choice, and
indeed Cassini-- which will orbit Saturn, but encounter Titan multiple
times during its mission-- is intended to carry SAR which will map a
handful of narrow strips of Titan as it swoops by.

I think Mars Observer and Mars 94 are appropriate, but I'm really
unhappy about the lack of priority given to studies of small bodies.
CRAF is dead, Vesta doesn't look too healthy, and Rosetta seems
awfully far away.  Maybe there is hope in the new smaller, faster,
allegedly-cheaper probes like SDIO's Clementine or the one APL is
supposed to be cooking up for NASA (LEAP, was it?).

The Moon definitely needs a going-over with Nineties instrumentation.
But you've heard me say that for years-- even *before* I met Dennis
Wingo. (-:

"Do you know the asteroids, Mr.Kemp?...    Bill Higgins
Hundreds of thousands of them.  All
wandering around the Sun in strange        Fermilab
orbits.  Some never named, never
charted.  The orphans of the Solar         [e-mail]
System, Mr. Kemp."
                                           [e-mail]
"And you want to become a father."
  --*Moon Zero Two*                        SPAN/Hepnet: 43011::HIGGINS

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

Date: Wed, 22 Jul 92 14:55:44 GMT
From: Doug Mohney <[e-mail]>
Subject: Magellan successors? (was Re: Support Lunar Resource Mapper Too!)
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Bill Higgins-- Beam Jockey) writes:

>Flying a Magellan-type mission to Mars or the Moon would be neat, too,
>but synthetic-aperture radar demands a heavy committment of
>tracking-network resources.

Why?

If you say "due to the large amounts of data sent back from the mission," I
got a great come-back for you :-)

   Previous signature chastized by Canadian Grad Student who flayed the United
   States as a bully from his bastion of free speech in Pittsburgh, PA.
                    Yes, fact IS stranger that fiction.
  -- >                  [e-mail]                        < --

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

Date: 22 Jul 92 15:16:03 GMT
From: Martin Connors <[e-mail]>
Subject: Magellan successors? (was Re: Support Lunar Resource Mapper Too!)
Newsgroups: sci.space

In article <[e-mail]> [e-mail]
(Bill Higgins-- Beam Jockey) writes:
> I asked Dr. Gordon Pettengill this question last year: "Is there a
> successor to Magellan?"
> The answer is no.

In a way, there is a successor to Magellan, but not for Venus. It is the
Canadian Space Agency's RADARsat, which will do SAR mapping of Earth. The
launch is scheduled in 1994.

It is not certain, however, that the data will be so widely or freely
distributed as that of Magellan, as RADARsat has a profit motive. We may
end up in more of a Landsat or SPOT-like situation, where there is great
interest in the data but thinking people cannot afford to get them.

Martin Connors - Space Research - University of Alberta

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

Date: 22 Jul 92 15:56:54 GMT
From: Martin Connors <[e-mail]>
Subject: Magellan successors? (was Re: Support Lunar Resource Mapper Too!)
Newsgroups: sci.space

In article <[e-mail]>
[e-mail] (Martin Connors) writes:
> It is not certain, however, that the data will be so widely or freely
> distributed as that of Magellan, as RADARsat has a profit motive. We may
> end up in more of a Landsat or SPOT-like situation, where there is great
> interest in the data but thinking people cannot afford to get them.

I note with interest in the EOS (Jul 7 1992) that arrived just after I
posted this, the new US National Landsat Policy Act, which will change how
Landsat data is available...to quote from the article:

"The Landsat Policy Act repeals provisions concerning commercialization of
Landsat data and requires that all data gathered by federal agencies be
made available to non-profit organizations at marginal cost, provided the
agency that collected the data deems that it will not be used
commercially."

The comments on RADARsat may still hold though. Even if Canada follows in
the US' footsteps in this, RADARsat is actually to be run by a separate
corporation...

 Martin Connors - Space Research - University of Alberta

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

Date: 23 Jul 92 00:33:29 GMT
From: Ron Baalke <[e-mail]>
Subject: Magellan successors? (was Re: Support Lunar Resource Mapper Too!)
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Bill Higgins-- Beam Jockey) writes...
>
>I asked Dr. Gordon Pettengill this question last year: "Is there a
>successor to Magellan?"  The answer is no.  Magellan is giving such a
>stupefying quantity of radar mapping data that it will take decades to
>sort it out, and no system giving, say, higher spatial resolution is
>currently planned.

The former Soviet Union was planning a Venera mission to Venus around
the year 2005, but those plans apparently have been dropped.  NASA has
no plans for a followup mission to Venus.  Because there won't be any
more Venus missions for at least 15 to 20 years, this is a good enough
reason to keep the Magellan mission going as long as possible, and to not
turn off the spacecraft next May which is what is currently planned.

>I think Mars Observer and Mars 94 are appropriate, but I'm really
>unhappy about the lack of priority given to studies of small bodies.
>CRAF is dead, Vesta doesn't look too healthy, and Rosetta seems
>awfully far away.  Maybe there is hope in the new smaller, faster,
>allegedly-cheaper probes like SDIO's Clementine or the one APL is
>supposed to be cooking up for NASA (LEAP, was it?).

Galileo's flyby of the asteroid Ida has been approved and will occur
on August 28, 1993.  The proposed NEAR mission has a very high likelyhood
of being approved and will be launched in 1998 and arrive at the Nereus
asteroid in 2000.
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Most of the things you
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | worry about will never
|_____|/  |_|/       |_____|/                     | happen.

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

Date: 22 Jul 92 14:37:41 GMT
From: James Davis Nicoll <[e-mail]>
Subject: Propulsion questions
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Nick Janow) writes:
>[e-mail] (Michael Ott) writes:
>
>> Just exactly how do you store antimatter?  I would think perhaps magnetically
>> suspended in a vaccuum, but can "vaccuum-enough" vaccuums be created?
>
>Sure.  Pump out most of the air, then spray in some antimatter to remove the
>rest of the air molecules.  :-)

    Which brings up the question of 'how hard a vaccuum is space and
how often will molecules impact the antimatter  fuel?' Even a block of
am in lunar orbit should lose *some* material due to interaction with the
solar wind, and  such.

                            James Nicoll

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

Date: 22 Jul 92 16:14:06 GMT
From: Henry Spencer <[e-mail]>
Subject: Propulsion questions
Newsgroups: sci.space

In article <cbeale.711757918@vela> [e-mail] (Christopher Beale) writes:
>I think there is some research going on somewhere with inertial propulsion.
>As it turns out, the old right-hand-rule with spinning disks appears to
>exert a minute force without the classical mass expulsion conservation of
>momentum deal...

I'd be very surprised to see any reputable research being done on such
subjects.  The slightest hint of a violation of conservation of momentum
would be screaming front-page news in physics, and there's been no such
news as far as I know.
--
There is nothing wrong with making      | Henry Spencer @ U of Toronto Zoology
mistakes, but... make *new* ones. -D.Sim|  [e-mail]  utzoo!henry

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

Date: Tue, 21 Jul 92 22:00:20 GMT
From: "Kalle T. Tuulos" <[e-mail]>
Subject: Testers for Astronomy Lab: NEW E-MAIL ADDRESS!!!
Newsgroups: comp.windows.ms,comp.windows.ms.programmer,comp.sys.ibm.pc.misc,sci.astro,sci.space,sci.edu

[e-mail] (Eric Bergman-Terrell) writes:

>*** Beta Testers Needed for Windows 3.X Astronomy Program ***

>Name: Kalle T. Tuulos
>US Mail Address: Pirttilahteenkatu 37, 20320 Turku, Finland
>E-Mail Address: [e-mail]
>Version of MS-Windows: 3.1
>Version of MS-DOS: 5.0
>CPU: 486DX2-50 + SX-12
>Math Coprocessor (not required): - + -
>Memory: 8MB + 2MB
>Graphics Card: Trident 8900C SVGA 1MB + IBM LCD-VGA
>Printer: Panasonic KX-P1124

--
Kalle T. Tuulos        [e-mail]
- a physics student from University of Turku, Finland

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

Date: Wed, 22 Jul 92 12:32:38 EST
From: [e-mail]
Subject: U.S. Black Programs

On 22 Jul 92 07:16:34 GMT Andrew Palfreyman asked:

>Please would you indicate the location of this "Antelope Valley"
>location?

Antelope Valley, California, 34.45 N 118.20 W, next to Edwards A.F.B.

J. Pharabod

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

Date: 22 Jul 92 11:59:17 GMT
From: Colby Kraybill <[e-mail]>
Subject: UFO-pic from Phobos2-probe posted !
Newsgroups: alt.alien.visitors,sci.space,alt.paranormal,sci.skeptic

In article <[e-mail]> [e-mail] (Stefan Hartmann) writes:
>Hi,
>
>I have posted the much discussed UFO-pic from the phobos 2 probe into
>
>alt.binaries.pictures.misc     and   alt.alien.visitors   newsgroups !
>

I am posting a follow up image to this "UFO-pic" that I think many people might
find to be interesting.  The image is in gif format and will be posted to
the same two groups mentioned above.


--
Colby Kraybill
Space and Planetary Image Facility
University of New Mexico

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

Date: 22 Jul 92 12:41:37 GMT
From: John Roberts <[e-mail]>
Subject: Visual acuity
Newsgroups: sci.space

-From: [e-mail]
-Subject: Re: Visual acuity for MS
-Date: 21 Jul 92 00:54:06 GMT
-Organization: NASA/JSC/GM2, Space Shuttle Program Office

-But there's a whole lot more than just the one number to be
-considered.  Astronauts, like pilots, can't be colorblind.  They
-have to be able to recognize warning colors.

--- Ken "20/200" Jenks, NASA/JSC/GM2, Space Shuttle Program Office
-      [e-mail]  [phone]

There are many degrees of color blindness ("challengedness"? :-), and very
few people are *totally* color blind. Is the restriction against *any*
degree of color blindness, or are there intermediate standards?

Are the Shuttle warning lights and color displays selected for maximum
visibility to partially color blind people (like traffic lights are supposed
to be)? There *are* legal standards for color selection in safety signals.

John Roberts
[e-mail]

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

Date: Wed, 22 Jul 1992 14:46:06 GMT
From: James Davis Nicoll <[e-mail]>
Subject: Visual acuity
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (John Roberts) writes:
>
>There are many degrees of color blindness ("challengedness"? :-), and very
>few people are *totally* color blind. Is the restriction against *any*
>degree of color blindness, or are there intermediate standards?
>
>Are the Shuttle warning lights and color displays selected for maximum
>visibility to partially color blind people (like traffic lights are supposed
>to be)? There *are* legal standards for color selection in safety signals.

    Hmmm. There are (according to a biologist I know) two possible
types of receptors for the colour green in human eyes (Peak reaction is
at two different frequencies). I wonder whether the slight difference
ever makes a difference in reading displays...

                            James Nicoll

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

Date: 22 Jul 92 12:07:07 GMT
From: John Roberts <[e-mail]>
Subject: Visual acuity in microgravity
Newsgroups: sci.space

-From: [e-mail] (Edward V. Wright)
-Subject: Re: Visual acuity for MS
-Date: 21 Jul 92 22:49:05 GMT
-Organization: Engineering, CONVEX Computer Corp., Richardson, Tx., USA

-As a side note, even astronauts with perfect vision (on Earth)
-usually wear contact lenses on orbit because the shape of the
-eyeball changes when there is no gravity to distort it.

A person who follows such things more closely than I do has told me that
wearing contacts in space is fairly unusual, because of the trouble handling
them in microgravity. One person on STS-50 did wear contacts, and they made a
point of showing him cleaning them and putting them in on the video downlink,
as though that were something fairly unusual.

Many of the astronauts wear glasses while in orbit. There are ongoing tests
of changes in visual acuity in microgravity, but I don't know whether anything
definitive has been found yet. I think the current theory is that fluid
shift may have some influence on the shape of the eyeball, rather than direct
gravitational distortion.

John Roberts
[e-mail]

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

Date: Wed, 22 Jul 1992 08:33:32 +0000
From: Geir Warhaug <[e-mail]>
Subject: Whales

Thanks to John Robert.

The whale we now hunt, is treathning to wipe out the Bluewhale.
There are more than one side in this case.

Geir

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

Date: Wed, 22 Jul 92 16:33:08 BST
From: [e-mail]
Subject: Whales and dolphins

The social structure of dolphins is among the most complex on Earth,
right up there with Homo Sapiens and Pan.

Dolphins form small cooperative groups that will sometimes form
coalitions with other cooperative groups. What is interesting is that
they may be the only other species that understands the double-cross
in the Machiavellian sense.

They will work with a group until it becomes in their interest to
work with yet another group against the first group.

This is often used by groups of males to kidnap (forcefully) and rape
female porpoises, and by female groups to attempt to prevent same.

So much for the peaceful, lovable porpoises... But they definitely
are far, far up the scale of social evolution.

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End of Space Digest Volume 15 : Issue 025
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