Message-ID: <sZSqCg-00VcJ898k5f@andrew.cmu.edu>
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From: space-request+@Andrew.CMU.EDU
To: space+@Andrew.CMU.EDU
Date: Tue,  5 Dec 89 01:43:56 -0500 (EST)
Subject: SPACE Digest V10 #311

SPACE Digest                                     Volume 10 : Issue 311

Today's Topics:
	   Re: Electronic Journal of the ASA, Vol. I, No. V
		Re: Manned vs Unmanned Mission to Mars
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Date: 4 Dec 89 17:47:29 GMT
From: bfmny0!tneff@uunet.uu.net  (Tom Neff)
Subject: Re: Electronic Journal of the ASA, Vol. I, No. V

From article <149@chara.UUCP>:
> THE ELECTRONIC JOURNAL OF THE ASTRONOMICAL SOCIETY OF THE ATLANTIC
> Volume 1, Number 5 - December 1989

> HOW TRUE IS OUR ASTRONOMICAL KNOWLEDGE? / THE CASE OF THE PLANETS
> by William G. Bagnuolo, Jr.

> How "sure" is our current astronomical knowledge?  Could firmly held
> beliefs by most astronomers be completely mistaken?  Sometimes it is
> instructive to look at the past record.  Patrick Moore's book, GUIDE TO
> THE PLANETS shows the state of "conventional wisdom" about our solar
> system in the year 1960.  Now, nearly thirty years later, we can see how
> many of those "facts" turned out to be true. ...

Here is an example of why confusing the popular and scientific
literature can be dangerous.  Judging the state of expert knowledge
in 1960 by what Patrick Moore (a fine guy to be sure) put in his book
is not really fair.  For one thing, the inherent *uncertainty* in
the various models active at the time is of necessity given short
shrift in a popular account.  It's not the job of GUIDE TO THE PLANETS
to tell you precisely how uncertain we are of each observation or
theory: only to pick the best theory and present it in layman's terms.
When the data is sketchy, the continuum of reasonable models tends to
be huge, and the "best" theory usually won't turn out to have been all
that great once lots of refining data arrives.

It would be interesting from the science historian's point of view if
perfectly unambiguous data on, say, the Martian surface were being
grossly *misinterpreted* or the existing data stretched *by scientists*
significantly further than the element of certainty could support.  I
have seen no evidence that this is so, nor does Bagnuolo supply any.
Browse through the stacks in your physics department some time: it is
clear that your working scientist was far more interested in deriving
meaningful numbers from polarimetry, radio measurements and whatnot,
than in playing Chesley Bonestell.

Perhaps the "our" in "OUR ASTRONOMICAL KNOWLEDGE" needs to be defined a
little better.  Whose knowledge is being questioned?  The people whose
job it is (and was) to find out -- astronomers and planetologists -- or
the casual layman who picks up snippets and hints of things from the
popular and entertainment media?  If the former, I claim that few were
"wrong," though many now have the detailed information they always knew
they needed in order to be "right."  If the latter, I claim that not
only was John Q Public "wrong" about the planets in 1960, he is quite
probably still "wrong" about them in 1989!  As for that middle ground of
"popularizers" and "artist's conception" makers, they print what looks
good according to the dictates of fashion (1960 or 1989), leavened with
actual mundane data where embarassment cannot otherwise be avoided.

-- 
There's nothing wrong with Southern California that a    || Tom Neff
rise in the ocean level wouldn't cure. -- Ross MacDonald || tneff@bfmn0.UU.NET

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Date: 4 Dec 89 17:40:43 GMT
From: attcan!utgpu!utzoo!henry@uunet.uu.net  (Henry Spencer)
Subject: Re: Manned vs Unmanned Mission to Mars

In article <1989Dec3.194731.23588@cs.rochester.edu> yamauchi@cs.rochester.edu (Brian Yamauchi) writes:
>>The best way to do an in-depth preliminary investigation of Mars would
>>probably be a mixed approach:  teleoperation from a manned vessel in
>>Mars orbit.
>
>A better alternative which would satisfy both camps might be a manned
>landing with multiple fully autonomous rovers (or even fliers)...

Well, note that I said "preliminary".  The definitive way to investigate
Mars is the same technique applied to Antarctica, North America, etc.:
send people.

A manned landing plus autonomous robots actually strikes me as the worst
of both worlds:  all the headaches of trying to design autonomous robots,
plus the practical problems of mounting a human expedition.
-- 
Mars can wait:  we've barely   |     Henry Spencer at U of Toronto Zoology
started exploring the Moon.    | uunet!attcan!utzoo!henry henry@zoo.toronto.edu

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End of SPACE Digest V10 #311
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