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Date: Wed, 22 Jul 92 05:02:07
From: Space Digest maintainer <digests@isu.isunet.edu>
Reply-To: Space-request@isu.isunet.edu
Subject: Space Digest V15 #023
To: Space Digest Readers
Precedence: bulk
Space Digest Wed, 22 Jul 92 Volume 15 : Issue 023
Today's Topics:
2nd (last) RFD sci.space.planets
Answers to PLANES of the ecliptic question
Astonomy Lab posted on comp.binaries.ibm.pc
Compiling a list of Internet/BITNET Physics Education resources
ESA Future
first man on moon date and time
Galileo Antenna. What's left to try?
No markets in space? (was Re: Chemical unit operations in space)
Propulsion questions (3 msgs)
Solar Events and Earthquakes
Solar Power Satellites
Visual acuity for MS
Whales (SETI)
Welcome to the Space Digest!! Please send your messages to
"space@isu.isunet.edu". Please do **NOT** send (un)subscription
requests to that address! Instead, send a message of the form
"Subscribe Space <your name>" to one of these addresses:
listserv@uga (BITNET), RICE::BOYLE (SPAN/NSInet),
UTADNX::UTSPAN::RICE::BOYLE (THENET), or
space-REQUEST@isu.isunet.edu (Internet).
----------------------------------------------------------------------
Date: 21 Jul 92 22:25:48 GMT
From: David Knapp <knapp@spot.Colorado.EDU>
Subject: 2nd (last) RFD sci.space.planets
Newsgroups: sci.space,news.groups,sci.astro
Another poke in the side to stimulate discussion of the formation of a
.planets group. The following has been discussed so far:
roberts@cmr.ncsl.nist.gov
Mentioned that people subscribing to SPACE Digest may be left in the dust
since they may want to read a .planets group, but couldn't access it. Seemed
optimistic that we could arrange to have them included somehow.
ctuel@zeus.calpoly.edu, ctuel@nike.calpoly.edu and *many others*
Suggested naming the group sci.space.planets or sci.astro.planets. I
considered sci.space.planetology to ilana@kiowa.scd.ucar.edu but was
told planets is better than planetology.
ilana@kiowa.scd.ucar.edu
Expressed concern that a .planets group might become a group full of religious
discussions and that
"there are
several existing groups which adequately cover all of your proposed
discussion areas. Creating a new group to bring all of these fairly
diverse areas (vulcanism [sci.geo.geology?], magnetospheres [sci.physics?],
pollution [sci.environment]) under one umbrella is confusing, will
dilute the discussions of those subjects in those groups, and is unnecessary,
IMHO."
and would also
">I would like very much for you to restate the charter such that the
>meteorological subjects (at least for terrestrial meteorology) are not
>included. We like them right here in sci.geo.meteorology, and would
>prefer to keep them in one place. I would imagine that planetary
>atmospheres might be an appropriate topic for sci.planets, but probably
>would be cross-posted to sci.geo.meteorology."
and reminds me that some of the topics in my original post are already
discussed in more terrestrially focussed groups. Topics like Ozone loss
global warming, and pollution might be good to keep out of a .planets
group.
adds that
"...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."
(which makes good sense and which we can certainly accomodate)
miller@rcf.rsmas.miami.edu
agrees with ilana@kiowa.scd.ucar.edu ,
"I agree completely with Ilana. In addition, if I am not mistaken, the
charters of both sci.geo.meteorology and sci.geo.fluids specifically
include discussion of atmospheres on other planets. In fact. s.g.f includes
discussion of all geophysical fluids which despite the "geo" includes
other planets in practice."
slb@slced1.nswses.navy.mil
was understandably shaken by my misconduct in netsemantics
"I am confused. The "formal" vote was negated for some reason, but this
got posted a second time. Will someone please clarify this situation."
(but we are all hip now, right?)
roberts@CMR.NCSL.NIST.GOV says that
"I am interested in it, too, but planetary science is also a major component
of sci.astro, which has an even larger bandwidth than sci.space. It would
help tremendously, I beleive, to have a .planets group, which would reduce
traffic on both groups, and also tend to make the subject matter on all
three (sci.astro, sci.space, and the new .planets group) more specific."
In response to slb@slced1.nswses.navy.mil's saying that
">Planetary science is a major component of sci.space, and I'm very interested
>in it. If you create sci.planets, then the people who have only limited
>Usenet access (me, for instance, at the moment, plus all the people on SPACE
>Digest once that's working again) won't be able to read it or post to it,
>thus limiting the participation in sci.planets and reducing the value of
>sci.space."
msb@sq.sq.com points out that
"If people can't keep their newsgroups straight with two closely related
groups, I think that having three will just make it worse. We will have
to read all three groups instead of two to get all the relevant articles,
and even more articles will be cross-posted inappropriately." and that
" I would also like to see terrestrial environmental
topics, which tend to get political even in sci.environment (or did before
I unsubscribed), kept separate from, uh, astronomical planetary science."
(something we probably would all like.)
roberts@cmr.ncsl.nist.gov reminds us that:
"There are at least two situations in which posting planetary material to
sci.space is entirely appropriate:
- In the context of a discovery by a space-related device (i.e. "Magellan
discovers active volcano on Venus").
- In the context of space exploration (i.e. "Mars is very cold and has a thin
unbreathable atmosphere, so environmental management will be a very
important for any visits by humans")."
otto@vaxb.acs.unt.edu
liked my idea about .planetology! and points out that having this name
will help because
"That way, we'll keep the postings of "Where
in the sky is Jupiter tonight?" and "Searching for planets around other stars"
in sci.astro where they belong."
These are just a few of the posted responses which went along with many
personal mail messages which may have contained less detail.
With all this, and other input, I conlcude that:
1) It would be important to make clear
that subjects in the .planets group *not* include fiery, politcally
charged terrestrial subjects like ozone loss and global warming unless
it was discussed strictly in a scientific conext as part of the larger
subject of planetary atmospheres.
2) The group should be called sci.astro.planets or sci.space.planets.
3) The group is perceived to be a potenetial threat to sci.space as
it might funnel away some subject matter but that it also might help
ease the traffic in the high volume .space and .astro groups.
4) Many feel that planetology can be covered in the currently existing
groups although some feel that much can be gained from having one group
with a focus on the subject.
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!
If there is specific input as to the charter of the group, please post
or mail it to me.
There will be a *real* CFV soon. Stay tuned.
Perhaps we should just try alt.sci.planetology and see how it goes?
--
David Knapp University of Colorado, Boulder
Highly Opinionated, Elderly and knapp@spot.colorad.edu
Perpetual Student of Chemistry and Physics.
Write me for an argument on your favorite subject.
------------------------------
Date: 21 Jul 92 09:35:44 GMT
From: Steven Robiner <srobiner@pollux.usc.edu>
Subject: Answers to PLANES of the ecliptic question
Newsgroups: sci.space,sci.astro
Thanks to all who responded to my question about the solar
system's plane of ecliptic relative to the galaxies. Almost
everyone who responded agreed that the number was about
60 degress. The rest of the details were most consisely
summed up by the following to respondents.
Thanks agian to all who responded.
=steve=
----------------
From: Hartmut Frommert
Dept. of Physics, University of Constance
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 ]
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.
Changes are due to
- galactic rotation (order of 200 million years, 0.2 arc secs per century)
This changes mainly only the node line. Only the inclination of solar
system's orbit around the galactic center changes *i_g* (periodically).
- angular momentum transfer to other stars/clusters/the Galaxy
which I assume you can forget.
-----------
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.
So the galactic equator is a plane going thru the galactic center
in Sag A perpendicular to this direction. It is outlined in
star atlases such as Wil Tirion's Sky Atlas 2000.0
Roughly, its a 63 degree tilt. Yes, this changes as the sun orbits
the galactic center. The solar motion is not simply circular, it also
moves up and down thru the disk of the galaxy. Look at an introductory
astronomy book for the period of the sun's orbit about the GC.
------------------------------
Date: 22 Jul 92 00:31:49 GMT
From: Bill Seward <seward@ccvax1.cc.ncsu.edu>
Subject: Astonomy Lab posted on comp.binaries.ibm.pc
Newsgroups: sci.space
I'm not sure if this is the program that has raised all the hoopla, but
a program called Astronomy Lab has been posted in 5 uuencoded parts on
comp.binaries.ibm.pc.
-------------------------------------------------------------------------------
| Bill Seward | |
| SEWARD@CCVAX1.CC.NCSU.EDU | Pithy saying wanted. Inquire within. |
| SEWARD@NCSUVAX.BITNET | |
-------------------------------------------------------------------------------
------------------------------
Date: 21 Jul 92 21:44:54 GMT
From: "Daniel L. MacIsaac" <danmac@maxwell.physics.purdue.edu>
Subject: Compiling a list of Internet/BITNET Physics Education resources
Newsgroups: sci.physics,sci.astro,sci.space,sci.edu
[descriptions of physhare, phys-l, tap-l, chemed-l, Spacelink, SpaceMet,
Newton deleted for brevity]
Thanks, Dave!
...maybe it is a trivial task to assemble an annotated bibliography on such
resources via email (if you will permit me the bandwidth). I would LOVE to
edit together and repost/redistribute such an annotated bibliography if others
are willing to provide material for it.
***HERE IS THE PUNCHLINE***
If YOU have or know of a Physics education related resource available via
the internet or bitnet (such as textfiles, databases, BBS, listserv, news-
groups, telnet sites etc), please send its name, complete access/joining info
and a short (1-3 line) description to me. (see examples appended)
I will assemble a 2 or 3 page catalogue and repost it. After it has
settled somewhat, I will determine some method of achiving it so it is
accessible to all Bitnet and Internet users, and I will update it periodic-
ally with new information as it is made available to me. I can cope with
being an archivist in the interest of remaining current on the topic of
physics education/the internet.
ADVthanksANCE
Dan
[Physics] '...is a narrow and rigid education, probably more so than any other
except perhaps in orthodox theology'
-- T.S. Kuhn, The Structure of Scientific Revolutions
Dan MacIsaac, Science Ed/Physics Grad Student, danmac@physics.purdue.edu
Examples:
> Listserves
>
> physhare
> subscribe at listserv@psuvm
> sharing resources for high school physics teachers
>
> phys-l
> subscribe at listserv@uwf
> college physics teachers with some K-12 participation
>
> tap-l
> subscribe at mailserv@appstate
> questions about physics, lab equipment - welcome K-12 questions
Catalogue so far (21 July 92):
physhare, phys-l, tap-l, chemed-l, Spacelink, SpaceMet, Newton
[Physics] '...is a narrow and rigid education, probably more so than any other
except perhaps in orthodox theology'
-- T.S. Kuhn, The Structure of Scientific Revolutions
------------------------------
Date: 21 Jul 92 21:14:53 GMT
From: "Philippos A. Peleties" <dominop@en.ecn.purdue.edu>
Subject: ESA Future
Newsgroups: sci.space
In article <63998@hydra.gatech.EDU> ccoprmd@prism.gatech.EDU (Matthew DeLuca) writes:
>In article <1992Jul21.160023.20724@en.ecn.purdue.edu> dominop@en.ecn.purdue.edu (Philippos A. Peleties) writes:
>>In article <63941@hydra.gatech.EDU> ccoprmd@prism.gatech.EDU (Matthew DeLuca) writes:
>
>>The point is this: ex-Soviet (Russian/Ukranian) technology most likely
>>will be used in some rather substantial capacity and some combination
>>of the above countries will become ESA members whether they are geographically
>>located in Europe or not.
>
>>It makes sense economically, politically and any other way there is to
>>measure things.
>
>I think the real point here is that you completely ignored what I wrote and
>simply poted what you would *like* to see.
>
>In principle, it would be good for the former Soviet states to cooperate
>with the ESA and contribute their storehouse of experience and knowhow.
>
>In practice, it's extremely unlikely. Funding for the ESA comes from contri-
^^^^^^^^^^^^^^^^^^^^^^^
I admire your confidence ;-) Am I the only one to be accused for wishful
thinking? :-)
>butions by the member nations, and there is no way the ex-Soviet states can
>afford it. The only way they could even consider it is if they completely
>scrapped their current space program and subordinate themselves to the ESA,
>which is unlikely, to say the least.
Yes, I'm aware of the funding mechanism inside ESA. And, yes, the ex-Soviet
states will not contribute money, but it's not money that ESA want's them
to contribute anyway. The most likely short-term arrangement they will
have for the time being is ESA putting the money and ex-Soviets putting the
knowhow and facilities as you so nicely put it. It is still a cost-effective
measure for ESA. The long-term arrangement will most likely be that of a
member state. There's nothing new here.
>
>I think what we are going to see happen is a fairly signifigant scaleback in
>Russian space activity for several years, followed by a gradual resumption to
>former levels around the turn of the century, when their economy starts to
>function again. As for the ESA, God only knows what is going to happen to
>them...probably bicker themselves to death.
>
Don't count on it. Standard politics in Europe. There will be a period of
minimal expenditure since Germany politically cannot afford not to scale back
as far as ESA funding is concerned... which points even more to the above
mentioned short and long-term approach.
>--
>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: ccoprmd@prism.gatech.edu _The Number of the Beast_
Philip Peleties
--
I speak for myself, I think for myself, I work for myself ... but I don't want
to play by myself ... so bring your toys and let's share ...
------------------------------
Date: 22 Jul 92 00:13:49 GMT
From: meyers@mcclb0.med.nyu.edu
Subject: first man on moon date and time
Newsgroups: sci.space
Can someone E-mail me the following information. I wouldlike to know
at what time the first man stepped on the moon and when it wass
televised. Direct ansewrs to : Meyers@mcclb0.med.nyu.edu
Thank you
OAM
------------------------------
Date: 21 Jul 92 20:44:53 GMT
From: Henry Spencer <henry@zoo.toronto.edu>
Subject: Galileo Antenna. What's left to try?
Newsgroups: sci.space
In article <1992Jul21.190805.4575@ucsu.Colorado.EDU> knapp@spot.Colorado.EDU (David Knapp) writes:
>What is the confidence (of the NASA team, not some net-philosophers)
>that thermal cycling will help?
Reportedly, it is now fairly low. It's always possible that the thing is
just about to pop out and one more cycle will do it... but the lack of
results is getting pretty discouraging.
>What else can be attempted? Thruster bursts? Fast rotation?
It's hard to exert much force with Galileo's teeny little thrusters.
And there are limits on the rotation rate the booms can take, which is
problematic because the antenna is much closer to the center of rotation.
About the best that can be done in this direction will be at Jupiter
orbit insertion, when the big -- well, relatively big -- maneuvering
engine is fired up, and spin is increased for better stability during
the engine firing.
You can shake the spacecraft a bit by moving other things, which is
going to be tried.
You can also try hammering on the deployment motor. It stalls quickly
when turned on steadily, but pulsing it might jerk things loose. That
too is going to be tried.
>What is the confidence that *some* technique will succeed?
Not too high.
>What is the schedule for more dramatic attmempts at freeing the antenna?
Nothing endangering the spacecraft will be tried until after the atmosphere
probe goes into Jupiter and its data is relayed back. That's a major mission
objective, and it can be done without the high-gain antenna.
Given the work being done right now on things like data compression, I
wouldn't give very high odds on anything endangering the spacecraft being
tried, ever. Much of the mission can be flown as is.
--
There is nothing wrong with making | Henry Spencer @ U of Toronto Zoology
mistakes, but... make *new* ones. -D.Sim| henry@zoo.toronto.edu utzoo!henry
------------------------------
Date: 21 Jul 92 23:44:51 GMT
From: Shari L Brooks <slb@suned1.nswses.navy.MIL>
Subject: No markets in space? (was Re: Chemical unit operations in space)
Newsgroups: sci.space
In article <63791@hydra.gatech.EDU> ccoprmd@prism.gatech.EDU (Matthew DeLuca)
writes:
>In article <1992Jul19.075544.29047@techbook.com> szabo@techbook.com (Nick
>Szabo) writes:
>>In article <1992Jul15.175830.1@fnalc.fnal.gov> higgins@fnalc.fnal.gov (Bill
>>Higgins-- Beam Jockey) writes:
>[Without lower costs for launching stuff from Earth, not a lot is going to be
>happening in space anytime soon]
>>An otherwise fine post, but this statement is a popular misconception.
>>The economics of space activity depend on both cost/lb. of transportation
>>and value/lb. of the goods transported (eg comsats). Value/lb. (eg
>>telephone circuits) has been increasing at a rate several orders of
>>magnitude higher than the decrease in cost/lb. If that trend continues
>>or accelerates, we will be processing materials in space long before
>>launch cost/lb. comes down significantly.
>You're mixing apples and oranges, Nick. Beaming signals up and sending them
>back down is in no way comparable to materials processing. In space-based
>telecommunications, once you have put your satellite in space, your transport
>costs are finished: you never have to launch anything again. Materials
>processing, on the other hand, is likely to be a continuing series of launches
>and retrievals, meaning that launch costs are going to be an ongoing expense.
While this may be true, nevertheless the basic comparison Nick makes is sound.
It is not merely dependent upon launch costs. This can again be extrapolated
from everyday ground-based life: there was recently a rail strike in these
parts, and the local agriculture suffered because the market value of the
goods did not cover the higher transportation costs of trucks.
While the value of COMSATs has nothing to do with materials processing, and
thus their value is immaterial to the discussion, I might remind you of the
recent shuttle experiments in growing the GaAs crystals. If production of
these can be set up in space, then perhaps transportation costs to market
will not be as large as other materials; as I recall one of the larger markets
for GaAs is for solar panels.
>I think Bill was right; we're going to need to see a signifigant drop in
>launch costs before the market really opens up.
I think that there will be no compelling reason to drop the launch cost until
there is an established market.
As an aside. The value (or rather, usefulness) of COMSATs is decreasing, not
increasing; also, they are getting more expensive relative to the superior
communications offered by fiber optics. While fiber optics will never replace
the usefulness of COMSATs in wide area broadcasting and in reaching mobile
users, I think that the days of point-to-point telecommunications utilizing
COMSATs are numbered.
--
Shari L Brooks | slb%suned1.nswses.navy.mil@nosc.mil
NAVSOC code NSOC323D | shari@caspar.nosc.mil
NAWS Pt Mugu, CA 93042-5013 |
--> All statements/opinions above are mine and mine only, not the US Navy's.
------------------------------
Date: 21 Jul 92 16:14:29 GMT
From: Michael Ott <astroatc!ott>
Subject: Propulsion questions
Newsgroups: sci.space
Just exactly how do you store antimatter? I would think perhaps magnetically
suspended in a vaccuum, but can "vaccuum-enough" vaccuums be created?
-michael "Back off man, I'm an Engineer"
ott%astroatc.uucp@cs.wisc.edu
Nope, I'm not speaking for Astronautics...
No really, I'm not.
------------------------------
Date: Tue, 21 Jul 1992 22:31:58 GMT
From: Christopher Beale <cbeale@vela.acs.oakland.edu>
Subject: Propulsion questions
Newsgroups: sci.space
rdouglas@cs.wpi.edu (Rob Douglas) writes:
>We were sitting around discussing this and not getting any where, so I decided
>to ask the experts.
Well, I'm far from an expert and actually consider myself in the dark about
life in general but...
>1) If a space ship used a fusion reactor for propulsion, how would that work?
>Doesn't there have to be something sent out the back of the ship, so
>that the ship has to conserve momentum and move forward? If so, then the
>amount of forward acceleration is limited by the weight carried by the ship
>at the start, and there is no way to have a very long term propulsion source.
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. Granted acceleration would be slow but theoretically it
could be sustained even in deep space. This may end up right there with
cold-fusion, the unicorn, and OSF1 so don't quote me. Heck, I may have
even imagined it during a recent airplane food-induced hallucination.
-chris
--
Christopher A. Beale | beale@grumpy.ksc.nasa.gov
Engineer, McDonnell Douglas Space Systems | cbeale@vela.acs.oakland.edu
I don't want anybody else, when I think of UNIX I touch myself.
--
--
Christopher A. Beale (non-prophet) | cbeale@vela.acs.oakland.edu
Engineer, McDonnell Douglas Space Systems | beale@grumpy.ksc.nasa.gov
"It's not the years honey, it's the milage."
------------------------------
Date: 22 Jul 92 01:56:58 GMT
From: John Roberts <roberts@CMR.NCSL.NIST.GOV>
Subject: Propulsion questions
Newsgroups: sci.space
-From: rmartin@yosemite.Rational.COM (Bob Martin)
-Subject: Re: Propulsion questions
-Date: 21 Jul 92 16:44:15 GMT
-nickh@CS.CMU.EDU (Nick Haines) writes:
->In article <rmartin.711643766@thor> rmartin@thor.Rational.COM (Bob Martin) writes:
-> What about Arthur C. Clarke's A-Drive. Blow a small stream of
-> reaction mass past a mini-black hole (A few tons??, the size of a
-> proton??)
-clearly you want to make sure that the singularity is massive enough
-such that its evaporation rate is slower than its accretion rate.
-Does anybody know what the relationships of mass to evaporation rate
-is? I was under the impression that explosive evaporation only took
-place when the singularity was very very small, i.e. < 1e6g or so.
I read it somewhere, but I don't remember the numbers. A black hole is rated
by its "temperature", which is a function of mass - the more massive the
black hole, the "colder" it is, and the slower its evaporation rate. A
black hole the mass of a star should take many times the current age of the
universe to evaporate. I seem to recall an estimate that a black hole the
mass of a "mountain" would be radiating fiercely, and very close to a final
"detonation". It sounds like a black hole large enough to do what you want
would be too massive for a reasonable-size spacecraft.
(Just to be on the safe side, please don't create any black holes in *this*
solar system until we know for sure. :-)
John Roberts
roberts@cmr.ncsl.nist.gov
------------------------------
Date: Tue, 21 Jul 1992 21:00:35 GMT
From: Charles Stuart <gtsrcls@srseis1.unocal.com>
Subject: Solar Events and Earthquakes
Newsgroups: sci.physics,ca.earthquakes,sci.space
>>>>> On 9 Jul 1992 20:14:43 -0700, srobiner@pollux.usc.edu (Steve Robiner) said:
Steve> NNTP-Posting-Host: pollux.usc.edu
Steve> Has anyone ever studied solar activity in relation to Earthquake
Steve> events?
Steve> =steve=
Ron and Nancy Reagan seem preoccupied with armagedon. Perhaps
their astrologer has dabbled in solar vs. seismicity
"relationships". But I'd call Pat Robertson and Oral Roberts to
verify this.......
------------------------------
Date: 21 Jul 92 23:51:59 GMT
From: Shari L Brooks <slb@suned1.nswses.navy.MIL>
Subject: Solar Power Satellites
Newsgroups: sci.space
In article <14d6jmINN65f@agate.berkeley.edu> gwh@soda.berkeley.edu (George William Herbert) writes:
>*Re: costs; Interesting new work suggests that it's possible to build
>a SPS in the 5 gigawat range (sort of standard sized) with about 85,000
^^^^^^^
>tons of mass, 99.4+-% of which can be lunar. Thus the potential cost
>is as low as 540 tons to GEO, plus lunar & L2 factories, plus the space
>transportration infrastructure to move stuff from a L2 factory to GEO.
>Which is half to an eighth of what earlier estimates looked like.
>The estimated cost of building an SPS is coming down, presuming that
>lunar materials work...
Does this new work assume that more than one will be built? The 540 tons
to GEO, does that cover only building the powersat or is it also including
whatever materials necessary to build the factories? Or is it assumeing
the infrastructure has already been in place and this is what it takes to
build one?
--
Shari L Brooks | slb%suned1.nswses.navy.mil@nosc.mil
NAVSOC code NSOC323D | shari@caspar.nosc.mil
NAWS Pt Mugu, CA 93042-5013 |
--> All statements/opinions above are mine and mine only, not the US Navy's.
------------------------------
Date: 21 Jul 92 22:49:05 GMT
From: "Edward V. Wright" <ewright@convex.com>
Subject: Visual acuity for MS
Newsgroups: sci.space
In <Brr7K9.BGn@zoo.toronto.edu> kcarroll@zoo.toronto.edu (Kieran A. Carroll) writes:
>Good point. One practical use of such a requirement, however, might
>be to provide a guideline for deciding when an active astronaut
>should retire. A number of the astronauts wear glasses on-orbit;
>likely many of them due to deteriorating eye-sight as they grow
>older. Even if all new-hires had 20-20 uncorrected vision, once they're
>in their 40's it'd start getting worse. The requirement may apply
>less to new-hires than to old hands.
On the contrary, the requirements are for new hires are much stricter
than the requirements for old hands. NASA, like the USAF, requires
*uncorrected* 20/20 for all pilot candidates, but a number of pilot
astronauts (including John Young, who was head of the astronaut office)
started wearing glasses as they got older. To the best of my knowledge,
none were ever dropped from the program because of deteriorating vision.
Requirements for perfect uncorrected vision are pretty silly;
the chances of a pilot having to fly with uncorrected vision
are pretty remote. (There are many thousands of civilain pilots
with less-than-perfect vision, and I have never heard of a plane
crashing as a result.) But NASA wants to maintain the image of
astronauts as physically perfect supermen and women for public-
relations purposes.
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.
------------------------------
Date: 22 Jul 92 01:44:55 GMT
From: John Roberts <roberts@CMR.NCSL.NIST.GOV>
Subject: Whales (SETI)
Newsgroups: sci.space
-From: phfrom@nyx.uni-konstanz.de (Hartmut Frommert)
-Subject: Re: Whale killing for "science" -- so for what?
-Date: 21 Jul 92 14:50:39 GMT
-Organization: Dept. of Physics, University of Constance
There was a discussion on sci.space about whale intelligence (wrt SETI) a
few years ago, but any files I saved on the subject are not currently
accessible, so this response is from memory.
-As a response to your statement I mention that I only listed few examples
-for the manifestation of the intelligence of whales. As was stated on
-sci.misc in the meantime, even the weight ratio brain/body is similar to
-human (!) for dolphins and orcas.
-FYI: The language of whales is based on sound (I think infra sound) and in
- the case of dolphins sufficiently developed so that they can communicate
- even without sight contact, and over larger distances. Covering the eyes
- of one dolphin and giving optical signals to a second is communicated to
- the first so that s/hecan react appropriately. Also think of the
- "songs of the whales" -- some people compare it to culture/art.
I believe they use mainly the audible frequency range, and perhaps up into
the ultrasonic. Keep in mind that many animals communicate by sound, and
it's no clear indicator of intelligence. It's necessary to analyze the
sounds for modulation characteristics, individuality, and degree of variation.
Many of the baleen whale songs, for instance, appear to be straightforward
repetitive patterns, and may well be no more communicative than bird calls.
I believe one baleen whale (the grey whale?) exhibits slow changes in its
songs over a period of months, which may (or may not) be indicative of
slightly higher intelligence.
-Message-ID: <phfrom.202@nyx.uni-konstanz.de>
-Date: 21 Jul 92 14:57:28 GMT
-I assume that many of the readers here are deeply interested in SETI,
-extra-terrestrial life (in particular, intelligent), etc.. How can one hope
-that there may be *any* useful (and peaceful) contact with ETI's if we
-are not even able to peaceful co-existence with the other TI's (the whales) ?
The usual argument is that we will be judged by the space aliens on how we
treat our lower species, so for instance if we expect to parasitize the
presumed greater learning and technology of alien species, we should be kind
to our own parasites - allow various blood-sucking creatures to live on our
bodies, let flies and rats eat off our plates before we do, etc. You seem to
be arguing that mistreating our whales makes us callous of the needs of other
species, and thus less likely to get along well with other species - so your
view at least shows some originality.
If we meet up with space aliens, they'll probably judge us on something we
consider really weird - like whether we punish our criminals fiercely enough,
or how piously we honor the memory of Elvis. :-)
-Please, no flames here. The discussion should stay on sci.misc.
So you can post your views here (and incorporate them in your signature),
but we're not allowed to reply here?
- Phone: +49-(0)7531-88-3747 | + Whales R intelligent. Whale killers not. +
Saying "whales are intelligent" is only slightly less general than saying
"mammals are intelligent". I believe there's considerable variation - most or
all of the baleen whales appear to be fairly stupid. Sperm whales may be
moderately intelligent, and also dolphins. (I've heard estimates of dolphin
intelligence put at somewhere between that of a very bright dog to "several
times that".) Perhaps the most intelligent non-primate (or even non-human)
animals on Earth are the killer whales (orcas). I'd like to know what the
current body of knowledge is on killer whale communications - some people
seem to think its complexity is akin to what we might call speech. Dolphins
and killer whales are both fierce predators, and both have shown considerable
promise in interacting with humans (maybe we think alike :-). I object to
the killing of killer whales and dolphins on these grounds.
My main objection to the killing of the less intelligent whales is that they
have traditionally been "over-harvested", thus depleting the population and
threatening a potentially valuable resource. (Tuna are also a very valuable
resource currently being over-harvested - you should feel guilty whenever
you eat tuna, if you're concerned about such things.) I would support a
moratorium or large cutback on whaling until the populations get back to
what they should be (I gather that even the species currently being harvested,
though they may have stable populations, have lower population than they once
had). In the meantime, studies can be conducted to determine whether any
species are particularly intelligent, and thus deserving of special
consideration.
-+ Whale killing is murder. Eating whales is cannibalism. Eat whale killers. +
Are we to enforce higher standards for our behavior toward whales than we
expect of them? Killer whales hunt and eat other whales. Does that mean
we should eat the "cannibal" killer whales?
John Roberts
roberts@cmr.ncsl.nist.gov
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End of Space Digest Volume 15 : Issue 023
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