Date: Fri, 16 Oct 92 05:00:05    
From: Space Digest maintainer <digests@isu.isunet.edu>
Reply-To: Space-request@isu.isunet.edu
Subject: Space Digest V15 #318
To: Space Digest Readers
Precedence: bulk


Space Digest                Fri, 16 Oct 92       Volume 15 : Issue 318

Today's Topics:
               Bootstrap hardware for LunaBase (3 msgs)
                         DCX Status? (2 msgs)
              Diesen sphere or Strungen Sphere (2 msgs)
                          HRMS/SETI Answers
                            Jobs-Aerospace
Mass driver/railgun literature (was Re: Transportation on the Moon.) (2 msgs)
         Math programs with arbitrary precision for the Mac?
                          NASA bugets....etc
                          orbital lifetimes
                  Query Re: pluto direct/ o (4 msgs)
                       SETI functional grammer
                Two-Line Orbital Element Sets, Part 2
                           V-2 anniversary
         With telepresence, who needs people in Earth orbit?
                        X-Ray Maps of Earth ?

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

Date: 15 Oct 92 13:04:55 GMT
From: Nick Szabo <szabo@techbook.com>
Subject: Bootstrap hardware for LunaBase
Newsgroups: sci.space

In article <ewright.719013536@convex.convex.com> ewright@convex.com (Edward V. Wright) writes:

>You snub comm sats in favor of mining the asteroids.

Huh?  Not at all.  I promote them both.  Furthermore, I think that
asteroid mining missions (and the volatile extraction missions that
will likely precede them) should use the same launchers as comsats,
instead of demanding their own special-purpose hardware.  That's
one big reason why comsats and the military are so important.  New 
large-scale commercial enterprises can't afford to build from scratch, 
and with a thriving, sharing space community there is no need for them to 
do so.  I have a big problem with proposals like SSF and FLO that soak up 
huge chunks of the budget in their own enclosed, built-from-scratch world, 
the result being they don't provide any benefits or economies of scale 
for other space users.  They are parasitic instead of symbiotic.

>Or maybe, just maybe, Nick, they have enough imagination to believe
>that space is big enough for more than *one* businesses.

I've dreamed up over a dozen original concepts which I've posted here,
while you repeat ancient dogma.  I've got you beat cold in the
imagination category. The issue here is the economic validity of these 
plans, the net present value that pops out of the spreadsheet.  That, 
more than any other single factor, is what will turn imagination into reality.

>Meanwhile, you refuse to be pinned down about any of the holes
>in your scheme, which depends on the commercial availability of
>AI technologies that don't exist even in the laboratory.

Automated volatile extraction requires good controls and high
reliability.  It does not require "AI", the definition
of which seems to be "the hard problems" -- as soon as
they're solved they're no longer AI.


-- 
Nick Szabo					 szabo@techboook.com
Hold Your Nose: vote Republocrat  ////////  Breathe Free: vote Libertarian

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

Date: 15 Oct 92 13:57:28 GMT
From: Nick Szabo <szabo@techbook.com>
Subject: Bootstrap hardware for LunaBase
Newsgroups: sci.space

In article <ewright.719011934@convex.convex.com> ewright@convex.com (Edward V. Wright) writes:

>[lotsa heated rhetoric]

Neither asteroid or lunar enterprises have any signficant commercial
funding.   Neither are ready for that yet.  My point is that these
enterprises can and should be analyzed from an industrial and
commercial viewpoint, and NASA should support them with exploration 
and tech R&D accordingly.  It is ridiculous to devote most of the resources 
to the moon because of obsolete "next logical step" dogma, or because
one wants to include astronauts. We need diveristy -- lunar exploration 
_and_ asteroid exploration _and_ comet exploration.  Doing them all
can be quite cheap if we start taking a sophisticated, in-depth look
at the problem and the technology available, instead of dogmatically
insisting on the traditional, ridiculously huge and expensive methods.  

We also need to look at the material needs of industry and start designing 
future commercial scenarios around the bottom line.  It is ridiculous
to focus on the moon when the vast majority of industrial processes
require volatiles, and by far the largest industrial input is volatiles,
and volatiles are not found on the moon.

>Every time someone mentions a potential
>project that is not backed by Nick Szabo Enterprises, you tell us
>that it's already been rejected by private enterprise. 

This is nonsense.  I've rejected two or three kinds of proposals,
out of a vast universe of possibilities.  You keep proposing the
same failed or grossly uneconomical strategies over and over again,
and I keep rejecting them over and over again.

>Why is anyone who advocates a manned space program, even one that's
>not run by the government, denounced as a socialist

Not by be.  But the economically ludicrous "private enterprise astronaut"
plays right into the hands of those who insist that government knows
best when it spends the majority of NASA $$$ on astronauts, and that
the needs of astronauts should dominate regardless of the needs
of our commerical and military space needs.  I'm objecting to NASA
dictation of the direction of space industry, especially the style that 
snubs the real users of space in commerce and the military.  I'm not 
objecting to rational, diverse government support for space R&D and 
exploration, or private attempts to do whatever they want with their
own money.  

>And why do you wax poetic about how your asteroid-mining robots 
>will allow thousands or millions of people to live in wonderful 
>colonies in space, with robots serving their every need, when you 
>so strongly deny that man is ever cost-effective in space.

I don't deny "ever", I deny "is".  It's not just me that strongly denies 
it; it is also in practice military and commercial users of space and 
most scientists.  And "is" does not mean "will always be".  One of the 
big benefits of extracting volatiles and organics, and after that metal 
regoliths, is that the cost of space habitation comes way down.  Ice 
rockets alone provide enough propellant and shielding to drop the cost 
of an astronaut Mars mission by a factor of ten.  So it turns out
that automation is critical to affordably living in space, not the 
enemy as the Luddite "manned is more flexible than unmanned" bozos portray 
it.


-- 
Nick Szabo					 szabo@techboook.com
Hold Your Nose: vote Republocrat  ////////  Breathe Free: vote Libertarian

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

Date: 15 Oct 92 16:24:08 GMT
From: Matthew DeLuca <ccoprmd@prism.gatech.EDU>
Subject: Bootstrap hardware for LunaBase
Newsgroups: sci.space

In article <1992Oct15.130455.9862@techbook.com> szabo@techbook.com (Nick Szabo) writes:

>I've got you beat cold in the imagination category. 

Absolutely correct.  Just look at the cost figures you post to this group. :-)
-- 
Matthew DeLuca             "We should grant power over our affairs only to
Georgia Tech                those who are reluctant to hold it and then only
Information Technology      under conditions that increase the reluctance."
ccoprmd@prism.gatech.edu              - Coda of the Bene Gesserit

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

Date: 15 Oct 92 14:59:57 GMT
From: Ian Taylor <se_taylo@rcvie.co.at>
Subject: DCX Status?
Newsgroups: sci.space

Allen Sherzer's countdown signature is telling us that the first DCX
flight is only six months from now, anyone know the current project status?

+-- I -------- fax +43 1 391452 --------------------- voice +43 1 391621 169 --+| T a y l o r  Alcatel-ELIN Research, 1-7 Ruthnergasse, Vienna A-1210 Austria  |+-- n ---- ian@rcvie.co.at --- PSI%023226191002::SE_TAYLOR --- 20731::ian -----+

                                    TBD

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

Date: 15 Oct 92 15:31:58 GMT
From: "Allen W. Sherzer" <aws@iti.org>
Subject: DCX Status?
Newsgroups: sci.space

In article <1992Oct15.145957.1003@rcvie.co.at> se_taylo@rcvie.co.at (Ian Taylor) writes:

>Allen Sherzer's countdown signature is telling us that the first DCX
>flight is only six months from now, anyone know the current project status?

Things are going on pretty well. My countdown may be off by a day or two
but there have been no serious problems with deisgn or construction.

On the political front, all the current threats have been eliminated and
in doing so, we showed Congress that there is considerable support for
SSTO (much to their supprise).

Focus is not moving to the DC-Y vheicle. Insiders are briefing Air force
people to convince them they need it. Sources say they are getting good
reviews from everybody they brief.

On the public front for DC-Y, a program has begun to visit every incoming
Congresscritter by early next year. A briefing packet to use has just been
completed and we are beginning to call (with good results) NSS chapters and
others looking for volunteers. If you are a US citizen and want to help,
drop me a line and I'll send you a packet.

  Allen


-- 
+---------------------------------------------------------------------------+
| Allen W. Sherzer | "A great man is one who does nothing but leaves        |
|  aws@iti.org     |  nothing undone"                                       |
+----------------------192 DAYS TO FIRST FLIGHT OF DCX----------------------+

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

Date: 14 Oct 92 18:18:11 GMT
From: Greg Hennessy <gsh7w@fermi.clas.Virginia.EDU>
Subject: Diesen sphere or Strungen Sphere
Newsgroups: sci.astro,sci.space

Henry Spencer writes:
#Use the outside, not the inside.  Arranging indirect lighting is left
#as an exercise for the student. :-)

Oh, in that case you get the gravitational field of the star at
whatever radius you build the SAS thing.

--
-Greg Hennessy, University of Virginia
 USPS Mail:     Astronomy Department, Charlottesville, VA 22903-2475 USA
 Internet:      gsh7w@virginia.edu  
 UUCP:		...!uunet!virginia!gsh7w

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

Date: 15 Oct 92 15:47:45 GMT
From: Henry Spencer <henry@zoo.toronto.edu>
Subject: Diesen sphere or Strungen Sphere
Newsgroups: sci.astro,sci.space

In article <1992Oct14.181811.29168@murdoch.acc.Virginia.EDU> gsh7w@fermi.clas.Virginia.EDU (Greg Hennessy) writes:
>#Use the outside, not the inside...
>
>Oh, in that case you get the gravitational field of the star at
>whatever radius you build the SAS thing.

Unfortunately, it's pretty feeble.  Solar gravitational acceleration at
Earth's orbit, for example, is under a milligee.
-- 
MS-DOS is the OS/360 of the 1980s.      | Henry Spencer @ U of Toronto Zoology
              -Hal W. Hardenbergh (1985)|  henry@zoo.toronto.edu  utzoo!henry

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

Date: Thu, 15 Oct 1992 09:49:25 GMT
From: Ian Taylor <se_taylo@rcvie.co.at>
Subject: HRMS/SETI Answers
Newsgroups: sci.space,sci.astro

In article <NICKH.92Oct14173825@VOILA.VENARI.CS.CMU.EDU> nickh@CS.CMU.EDU (Nick Haines) writes:
>In article <1992Oct14.161418.5759@rcvie.co.at> se_taylo@rcvie.co.at (Ian Taylor) writes:
>
>   Why can't HRMS detect a current earth-like technology leakage at
>   interstellar distances? Isn't this the most likely case?
>
>Why is this the most likely case? 
My assumption is that technologies using microwave communications will do so 
primarily for their own benefit, not to send interstellar messages. Using 
the one observation available as supporting evidence is clearly unfair, so
I won't :-) 

>We can't assign any probabilities to levels of technology or power use by ETs.
Why not? Doing so of course is risky, but that is part of the fun :-) 
BTW SETI work is partly justified by Drake's equation, which explicity assigns
probabilities to assumptions about the fraction of intelligently-inhabited
planets using radio technology.

+-- I -------- fax +43 1 391452 --------------------- voice +43 1 391621 169 --+
| T a y l o r  Alcatel-ELIN Research, 1-7 Ruthnergasse, Vienna A-1210 Austria  |
+-- n ---- ian@rcvie.co.at --- PSI%023226191002::SE_TAYLOR --- 20731::ian -----+

                                  TBD 

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

Date: 15 Oct 92 17:03:01 GMT
From: William Fabanich <WAF102@psuvm.psu.edu>
Subject: Jobs-Aerospace
Newsgroups: sci.space

Anyone have an approx. number for the number of people employed by gov and indu
stry who do any related work with the space program ?

   Thanx...Bill Fabs    waf102@psuvm.psu.edu

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

Date: 15 Oct 92 03:22:14 GMT
From: Keith Harwood <keithh@tplrd.tpl.oz.au>
Subject: Mass driver/railgun literature (was Re: Transportation on the Moon.)
Newsgroups: sci.space

In article <1992Oct13.001407.1@fnala.fnal.gov>, higgins@fnala.fnal.gov (Bill Higgins-- Beam Jockey) writes:
. . . Put manufacturing plant at the Lunar north pole.
. . .
> mirrors on a tall tower can give you power 28 days around the clock
> there, too.)

I was under the impression that the moon's axis had much
the same obliquity to the ecliptic as the Earth's, so either
you have very tall towers or six month's light and six
month's dark. (If the moon's axis was normal to the ecliptic
we would get about 28 degrees of north-south libration and
I'm sure it's only about five degrees.) 

Keith Harwood.

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

Date: 15 Oct 92 15:49:52 GMT
From: Henry Spencer <henry@zoo.toronto.edu>
Subject: Mass driver/railgun literature (was Re: Transportation on the Moon.)
Newsgroups: sci.space

In article <1992Oct15.132708.14377@tpl68k0.tplrd.tpl.oz.au> keithh@tplrd.tpl.oz.au (Keith Harwood) writes:
>I was under the impression that the moon's axis had much
>the same obliquity to the ecliptic as the Earth's...

Nope, wrong.  The Moon's axis is almost precisely perpendicular to the
ecliptic; the Sun is permanently just on the horizon at the lunar poles.
This is one reason for optimism about frozen volatiles at the poles --
the bottoms of polar craters never see sunlight.
-- 
MS-DOS is the OS/360 of the 1980s.      | Henry Spencer @ U of Toronto Zoology
              -Hal W. Hardenbergh (1985)|  henry@zoo.toronto.edu  utzoo!henry

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

Date: Wed, 14 Oct 1992 17:56:00 GMT
From: IGOR <i0c0256@rigel.tamu.edu>
Subject: Math programs with arbitrary precision for the Mac?
Newsgroups: sci.space

In article <seal.719016011@leonardo>, seal@leonardo.Jpl.Nasa.Gov (David Seal) writes...
>Having been duly inspired by an episode of northern exposure i tried
>fiddling with ramanujan's and borwein and borwein's formulas for 
>computing pi on my mac.  however, the floating point accuracy
>for MATLAB (which i was using) isn't settable and i can't get past
>the sixteenth decimal place or so.  other mac programs or ways of computing
>pi?  thanks.


a very simple way of computing pi is as follows:
pi/4=4*atan(1/4)+atan(1/239) i may actually mess up the argument in front
of the atan so you would have to check on a calculator.

The fancy thing about this instead of using pi=4*atan(1),  one can expand
the atan in term of series atan =x -x^3/3+x^5/5-x^7/7 with a radius of 
convergence of r=1, which means it this specific case that the acceleration of
convergence will be tremendous if you are using arguments less than 1 such as
1/4 and 1/239. With this formula, the problem of finding pi is to develop
routines doing subtraction,addition and division of infinitely long numbers...\
which is a problem that one probably solved in sixth grade...
I think that after the third term computed i was able to get a seven digit 
accuracy... not bad




Igor
Texas A&M University
--------------------------------------------------------------------------
Its a nice bike
	terminator 2
-----------------------------------------------------------------------------

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

Date: 15 Oct 92 16:40:55 GMT
From: William Fabanich <WAF102@psuvm.psu.edu>
Subject: NASA bugets....etc
Newsgroups: sci.space

I would like any info you experts might know of the top of your heads...or wher
e to find it...about NASA bugets/ Military space bugets...and any comparison wi
th other governement agencies....something for me to show that the amount we sp
ent on space is not really enough to solve all our countries ills.
  Thanx!
    Bill Fabs

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

Date: 14 Oct 92 23:36:40 GMT
From: Bruce Watson <wats@scicom.AlphaCDC.COM>
Subject: orbital lifetimes
Newsgroups: sci.space

In article <BvtKsG.HAD@zoo.toronto.edu| henry@zoo.toronto.edu (Henry Spencer) writes:
|In article <28396@scicom.AlphaCDC.COM| wats@scicom.AlphaCDC.COM (Bruce Watson) writes:
|||How many of these moons have stable orbits?  In this case, I define stable
|||to mean that they will stay in orbit for 100+ years...
||
||Anything above 1000 km will stay up for 100+ years...
|
|At lower altitudes there's a nice set of rules of thumb...
|
|At 100km your orbit lasts about an hour.
|At 150km your orbit lasts about a day.
|At 200km your orbit lasts about a week.
|At 250km your orbit lasts about a month.
|At 300km your orbit lasts about a quarter.
|At 350km your orbit lasts a bit under a year.
|
|Don't plan missions on this basis. :-)  Furthermore, don't try to extrapolate

|it further:  the more-or-less semilog relationship you would infer from it
|is visibly failing on both ends.  It's actually more like log-log, and the
|constants vary a lot with how dense your satellite is.

I put together some data from the graph on p. 153 of Bate, Meuller, and
White and some empirical data (all of it less than 35 years, of course)
and came up with results very much like these. My best fit is:

log_10 t_years = 7.4 log_10 a_km - 19.1

where t is time and a is altitude above the surface of the earth of the
circular orbit (except for Molniyas virtually all are these days).

Of course the atmospheric density varies daily, tidally with the sun
and the moon, annually and with the sun spot cycle, so the fit can
only be approximate.

As you say, the density of the satellite matters. Especially with the
balloon satellites of the 60's. Echo I lasted 8 years from its 1600 km
orbit. Had it been more iron than air it would still be up there with
10's of thousands of years to go.

-- 
Bruce Watson (wats@scicom)  Tumbra, Zorkovick; Sparkula zoom krackadomando.  

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

Date: Wed, 14 Oct 1992 18:37:00 -0500
From: Tomas Svitek <Tomas.Svitek@f118.n109.z1.fidonet.org>
Subject: Query Re: pluto direct/ o
Newsgroups: sci.space

HS>>Aerobrake?

HS>In what? :-)  Pluto does have an atmosphere of sorts at the moment, but
HS>I'd guess it's too thin to do much aerobraking in, even if we knew its
HS>properties well enough to plan an aerobraking mission, which we don't.
HS>And we'd have to kill a lot of velocity; Pluto is roughly 150 km/s-years
HS>away (how's that for strange units? :-)), so for a reasonable trip time
HS>we're talking about killing maybe 20 km/s, which is high.

Actually, there is a fairly serious proposal (albeit very tentative)
from GE Reentry Systems regarding aerobraking at Pluto.  Surprisingly,
they claim that it can be done, with the inflatable heat shield.  I guess
that because you are moving so fast, the atmospheric drag is very high.

I cannot judge the proposal on its technical details, but they sound quite
serious, and they *know* about heat shields.  It is, however, true that
by far the biggest problem is absolute uncertainity about the postulated
Pluto atmosphere.

                        Tomas Svitek
  OLX 2.1 TD  Back Up My Hard Drive? I Can't Find The Reverse Switch!

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

Date: Wed, 14 Oct 1992 18:38:00 -0500
From: Tomas Svitek <Tomas.Svitek@f118.n109.z1.fidonet.org>
Subject: Query Re: pluto direct/ o
Newsgroups: sci.space

HS>It is extremely difficult to combine a reasonable payload and a manageably
HS>short trip time with an orbiter mission.  Pluto is *a long way away*; to
HS>get there in under a decade, the probe has to be fast.  Killing all that
HS>velocity is inordinately expensive in mass.  You really cannot do a Pluto
HS>orbiter in a reasonable amount of time with 1960s propulsion technology,
HS>which is what all currently-planned missions use.

Unless you use a *very* close Jupiter flyby, around 2003 timeframe.

                        Tomas Svitek
  OLX 2.1 TD  Back Up My Hard Drive? I Can't Find The Reverse Switch!

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

Date: 15 Oct 92 13:46:00 GMT
From: Greg Macrae <spgreg@mars.lerc.nasa.gov>
Subject: Query Re: pluto direct/ o
Newsgroups: sci.space

I missed the original post or I would have followed up by mail...
>HS>It is extremely difficult to combine a reasonable payload and a manageably
>HS>short trip time with an orbiter mission.  Pluto is *a long way away*; to
>HS>get there in under a decade, the probe has to be fast.  Killing all that
>HS>velocity is inordinately expensive in mass.  You really cannot do a Pluto
>HS>orbiter in a reasonable amount of time with 1960s propulsion technology,
>HS>which is what all currently-planned missions use.

NASA JPL and NASA LeRC studies show that a Pluto orbiter is possible with 
a 10 year or less time frame, launching with an expendable, chemical first
stage if you are willing to fly nuclear electric propulsion.  
--------------------------------------------------------------------
     MacRae                  |      Bright red pepper pod...
                             | It needs but shiny wings and look...
  spgreg@mars.lerc.nasa.gov  |        Darting dragonfly!
                             |                      -Basho
--------------------------------------------------------------------

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

Date: 15 Oct 92 16:29:50 GMT
From: Doug Mohney <sysmgr@king.eng.umd.edu>
Subject: Query Re: pluto direct/ o
Newsgroups: sci.space

In article <15OCT199209461657@mars.lerc.nasa.gov>, spgreg@mars.lerc.nasa.gov (Greg Macrae) writes:
>I missed the original post or I would have followed up by mail...
>>HS>It is extremely difficult to combine a reasonable payload and a manageably
>>HS>short trip time with an orbiter mission.  Pluto is *a long way away*; to
>>HS>get there in under a decade, the probe has to be fast.  Killing all that
>>HS>velocity is inordinately expensive in mass.  You really cannot do a Pluto
>>HS>orbiter in a reasonable amount of time with 1960s propulsion technology,
>>HS>which is what all currently-planned missions use.
>
>NASA JPL and NASA LeRC studies show that a Pluto orbiter is possible with 
>a 10 year or less time frame, launching with an expendable, chemical first
>stage if you are willing to fly nuclear electric propulsion. 

I suspect you can't get much mileage out of this but...

Couldn't you use a chemical first stage, then deploy a solar sail to add on
some speed, dump it when dragging the mass around is more of a penalty than the
speed you get from it...?


                 Play in the intelluctual sandbox of Usenet 

  -- >                  SYSMGR@CADLAB.ENG.UMD.EDU                        < --

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

Date: Thu, 15 Oct 1992 05:06:43 GMT
From: Robert J Woodhead <trebor@foretune.co.jp>
Subject: SETI functional grammer
Newsgroups: sci.space

jbh55289@uxa.cso.uiuc.edu (Josh 'K' Hopkins) writes:

>I ran across a thought experiment once where the prototype teleporting machine
>ends up on an alien planet and won't come back.  How do you tell the aliens
>to press the right (manual override) button and not the left (self destruct)
>button?  I couldn't figure a way out.

Describe it in terms of physical properties, including the RIGHT-HAND
rule.

Physics is the same (almost) everywhere.
-- 
+---------------------------------------------------------------------------+ 
| Robert J. Woodhead, Biar Games / AnimEigo, Incs.    trebor@foretune.co.jp |
|  Fundamental Mistakes in the design of the World's User Interface, #3217  |
|                   "Elevators don't have CANCEL buttons"                   | 

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

Date: Thursday, 15 Oct 1992 08:50:37 CET
From: TNEDDERH@ESOC.BITNET
Subject: Two-Line Orbital Element Sets, Part 2
Newsgroups: sci.space

Thanks for posting the elements.

    -Thorsten-

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

Date: 14 Oct 92 17:45:46 GMT
From: Bruce Watson <wats@scicom.AlphaCDC.COM>
Subject: V-2 anniversary
Newsgroups: sci.space

In article <2560007@hpdmd48.boi.hp.com+ rrr@hpdmd48.boi.hp.com (Rudi Rynders) writes:
+###/ hpdmd48:sci.space / techno@zelator.in-berlin.de (Frank Dahncke) / 10:37 am  Oct  4, 1992 /
+###In <28165@scicom.AlphaCDC.COM- wats@scicom.AlphaCDC.COM (Bruce Watson) writes:
+###
+###-Trivia question: Which city was targeted and hit by the most number
+###-of V-2s?
+###
+###Amsterdam, Holland.
+###
+###							  Techno
+###-- 
+###| techno@zelator.in-berlin.de ||| Please do not e-mail from outside Germany ! |
+###| techno@lime.in-berlin.de   / | \  Hardcore ST user ! ====================== | 
+###| Nothing that's real is ever for free, you just have to pay for it sometime. |
+###|                                       (Al Stewart)                          | 
+###----------
+You can be sure that is was NOT Amsterdam. I witnessed many launchings of V-2's
+during 1944 and the first half of 1945 from around The Hague, and while some
+malfunctioning ones landed in The Hague, I can not remember any falling on
+Amsterdam. Furthermore Amsterdam is more than 90 degrees from the bearing for
+England from  most launching sites.
+London was the biggest target within the actionradius of the V-2,
+and it took quite a few hits. However since this is a trivia question , the poser
+is probably thinking of one the industrial cities in southern England.
+
+Rudi Rynders (rrr@hpdmd48.boi.hp.com)

Amsterdam in incorrect and Antwerp took more hits than London. See my previous post.

-- 
Bruce Watson (wats@scicom)  Tumbra, Zorkovick; Sparkula zoom krackadomando.  

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

Date: 15 Oct 92 07:41:38 GMT
From: Gary Coffman <ke4zv!gary>
Subject: With telepresence, who needs people in Earth orbit?
Newsgroups: sci.space

In article <Cohena-061092082023@l30346.mdc.com> Cohena@mdc.com (Andy Cohen) writes:
>I'm not sure...but it seems that Allan doesnt support the notion of
>telerobotic exploration....consider this...
>If the location can be scanned with enough detail,..then the data
>transmitted back to Earth.... a vitual simulation can be constructed
>Earthside.  Use of telerobotic interfaces using a form of batch commanding
>can be feasible...  Earthside builds the batched commands using the virual
>simulation then transmits...  The scan is performed again after the
>completion of the commands as feedback again to the virtual simulation
>Earthside....
>The technical challenges include the scanning device, the throughput for
>the scanned data back to Earth and the simulation Earthside....all are
>easily solved...

I can't speak for Allan, but I certainly think that telerobotics is
handicapped by lack of force feedback and kinesthetic sensing. Over 
dependance on visual scanning misses too much information necessary 
for control. You can't tell by visual scanning if that rock will turn 
if weight is placed on it. You can't tell by visual scanning if the 
surface ahead will subside. You can't tell if a cliff edge is just the 
other side of that rock you just told the robot to climb. Etc. 
It's likely that most of these issues can be dealt with on board the
robot, but it certainly isn't *easily* solved.

Plus there are issues of the lack of on board curiosity that would
cause one to look quickly in the direction of an odd sound or notice
an odd shading on a rock that the visual scanner might miss due to
spectral limitations. I deal with television every day on a professional
basis. I know how limiting a TV view is. Telerobotic exploration is lots 
cheaper for a quick look at a surface than manned exploration, but not as 
through and more likely to miss anomalies that it was not programmed to 
find. The most important discoveries are often the ones you *aren't*
looking for.

Gary

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

Date: 15 Oct 92 09:37:18 GMT
From: Alan Carter <agc@bmdhh286.bnr.ca>
Subject: X-Ray Maps of Earth ?
Newsgroups: sci.space

In article <965529.16757@ABBS.zer.sub.org>, m.breunig@abbs.hanse.de (Max Breunig) writes:
|> 
|> 
|> From: UUCP/Sci/Astro
|> >Betrifft         : X-ray map of N. California
|> >Erstellungsdatum : 07.10.92 18:08
|> >
|> >From: J103680@LMSC5.IS.LMSC.LOCKHEED.COM
|> >Message-Id: 92279.49812.J103680@LMSC5.IS.LMSC.LOCKHEED.COM
|> >Organization: Lockheed Missiles & Space Company, Inc.
|> >
|> >I am searching for an X-ray map of Northern California to
|> >reveal caves and caverns underground.  Know of any sources?
|> >
|> Sounds interesting !
|> I have never heard of any X-ray maping of earth.
|> Knows anyone of such a project and some details on it ?

Er... Guys, how *hard* are these X-rays going to be? 
Should I hide the family jewels behind the moon, or would 
a small asteroid be sufficient :-)

   Alan

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   Maidenhead itself is too snobby to be pleasant. It is the haunt of the
   river swell and his overdressed female companion. It is the town of showy
   hotels, patronized chiefly by dudes and ballet girls. 

   Three Men In A Boat, Jerome K. Jerome, 1889
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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End of Space Digest Volume 15 : Issue 318
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