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From: fcrary@rintintin.Colorado.EDU (Frank Crary)
Newsgroups: sci.space.policy,sci.astro,alt.sci.planetary,sci.astro.amateur
Subject: Re: Sagan (was Re: AAAS News Release! The Details!! Signs of Past Life 
	on Mars)
Date: 11 Aug 1996 17:03:07 GMT

In article <4uh2r3$e9e@rosebud.sdsc.edu>,
Mike Gannis  <mgannis@sdsc.edu> wrote:
>:... As far as Sagan is concerned, most astrophysicists I know
>:don't have a problem with his popularization of science.  What my 
>:associates seem to find distasteful is the perception by the
>:general populace that Sagan is a brilliant astrophysicist.  He's very
>:good at writing science on a level for those without doctorates in
>:the field, but my astro friends don't have much respect for the actual
>:science he's *done*. ...

>Where are your astro friends?  Sagan is respected in the field of
>planetary science, has made some worthwhile discoveries (and predictions
>based on theory that were later borne out by the data), and founded a
>major journal in the field (_Icarus_).

Have you actually read any of Sagan's papers? As far as I know, he
hasn't made any discoveries or predictions borne out by later data,
and his works include such gems as:

Assuming ice is completely transparent, no matter how thick it is...
	(From a paper on ice covered rivers to explain the valley
	networks on Mars)

Assuming the shape and interconnections between seas do not affect
	tidal dissipation... (From a paper on the existence or
	nonexistence of oceans on Titan)

(Note that he did not say either of those things in the paper. He
just made those assumptions without mentioning it, even though they
are incorrect and drastically alter the results.)

He identified the "colors" in the Voyager images of Io with high-temperature
	alotropes of sulfur, despite the fact that those temperatures
	are totally inconsistent with IR measurements and without
	bothering the check about the details of the images. It
	turns out that they aren't true color images (frames were
	taken with the red, blue and violet filters and displayed
	as red, green, blue.) 

I don't even want to get into the "nuclear winter" business, except
	to mention that it's wrong and most atmospheric scientists
	consider the paper to be a joke.

                                                         Frank Crary
                                                         CU Boulder



From: Geoffrey A. Landis <geoffrey.landis@lerc.nasa.gov>
Newsgroups: sci.space.policy,sci.astro,alt.sci.planetary,sci.astro.amateur
Subject: Re: Sagan
Date: 14 Aug 1996 13:24:03 GMT

In article <4usfrv$eie@cwis-20.wayne.edu> Michael Edelman,
mje@pookie.pass.wayne.edu writes:
>...
>And of course Sagan is not a meteorologist. He was recruited for his 
>popular reputation, not for any skills he brought ot the project. 
>...

To the contrary, Sagan's actual scientific field was the study of dust on
Mars.  If you look at the early papers on Mars atomospherics, you will
see Toon, Pollack, and Sagan (the TPS part of TTAPS) all over the place.  

Since original the "nuclear winter" scenario was initially the result of
looking at the effect of suspended particulates on climate on *Mars*,
it's completely reasonable that Sagan would be one of the authors.

____________________________________________
Geoffrey A. Landis,
Ohio Aerospace Institute at NASA Lewis Research Center
physicist and part-time science fiction writer



Newsgroups: sci.space.policy,sci.astro,alt.sci.planetary
From: Henry Spencer <henry@zoo.toronto.edu>
Subject: Re: Nuclear Winter (was: AAAS News Release! The Details!! Signs of 
	Past Life on Mars)
Date: Wed, 14 Aug 1996 17:19:47 GMT

[I've made some selective deletions from the Newsgroups line.]

In article <4up5ef$a1i@dfw-ixnews9.ix.netcom.com> tomspain@ix.netcom.com (Tom Spain) writes:
>From what I saw of Sagan's views he was simply trying to point out the
>absolutely lunatic position all mankind was in because of the doctrine
>of MAD (mutually assured destruction)...

Most of us didn't need this pointed out, actually.  (And note, by the way,
that MAD was no longer US doctrine at the time, and had never been Soviet
doctrine at all.  Far too many people greatly diminished the effectiveness
of their protests by never bothering to learn the details of what they were
protesting against.)

>I rather think that the nuclear winter scenario after a major
>thermonuclear exchange was overstated only slightly, if at all...

Try "seriously" or even "heavily".  Sagan et al did do us all a major
service by pointing out an issue that had formerly been overlooked -- the
potentially serious effects of releasing large amounts of soot into the
upper atmosphere -- but they couldn't resist exaggerating the numbers for
PR purposes. 

>Didn't the Shoemaker-Levy impacts on Jupiter have much greater (and
>scarier) effects than predicted by virtually all of the scientists
>beforehand? ...

Not quite.  The effects were much more *visible* than anyone had thought,
but they seem to have actually been rather below prediction in most other 
ways, to the point where estimates of the actual size of the SL9 pieces
have shifted sharply downward.

>To err in any direction except on the side of caution in
>this regard would be more madness.

That depends on the price of erring on the side of caution, which
typically is not zero.  You have to evaluate these things carefully,
bearing in mind that you pay the price for precautions even if the evil
you are taking precautions against never comes.  There is such a thing
as paying too much for too little gain.

>...the danger is actually increasing. There is certainly no shortage of
>individual, organizational and national 'terrorist nuts' in the world
>today who would not hesitate to use such 'tools' if they could get
>their hands on them.

While this is certainly a serious issue, note that it is *not* the same
problem.  Now we are concerned about isolated acts of destruction, rather
than the possibility of civilization-destroying global holocaust.

Note also that intelligent, sophisticated terrorists do not need nuclear
weapons to cause widespread destruction and massive death tolls.  There
are easier ways.  The fact that we don't *already* have a problem suggests
that either (a) terrorists generally lack intelligence and sophistication,
or (b) they (or perhaps their sponsors) perceive such large-scale attacks
as counterproductive. 
-- 
 ...the truly fundamental discoveries seldom       |       Henry Spencer
occur where we have decided to look.  --B. Forman  |   henry@zoo.toronto.edu



Newsgroups: sci.space.policy,sci.astro,alt.sci.planetary
From: Henry Spencer <henry@zoo.toronto.edu>
Subject: Sagan politics (was Re: AAAS News Release! ...)
Date: Thu, 15 Aug 1996 14:46:39 GMT

In article <Dw2u2y.AGE@novice.uwaterloo.ca> sen@sun14.vlsi.uwaterloo.ca (Subhajit Sen) writes:
>>And Sagan's and Russell's views were dangerous, considering the very real 
>>threat that the Soviet Union posed to the world...
>
>	The British used to say the same thing about Germany
>(i.e. they were a threat to the world) before WW-I and WW-II...

Yes, and the British were *right*, particularly before WW2.

>...All Sagan said, in
>the book "The pale blue dot" is that international cooperation and
>peace are necessary if mankind is to achieve the glory of inter-planetary
>space travel...

A peculiar statement, considering that the interplanetary space travel
which has been accomplished to date was mostly spurred by international
competition and ideological warfare.  Sagan is letting his agenda warp
his judgement; he wants international cooperation so badly that he sees
it as the answer to everything.
-- 
 ...the truly fundamental discoveries seldom       |       Henry Spencer
occur where we have decided to look.  --B. Forman  |   henry@zoo.toronto.edu



From: fcrary@rintintin.Colorado.EDU (Frank Crary)
Newsgroups: sci.space.policy,sci.astro,alt.sci.planetary
Subject: Re: Sagan
Date: 20 Aug 1996 00:35:29 GMT

In article <4vadut$c70@rosebud.sdsc.edu>,
Mike Gannis  <mgannis@sdsc.edu> wrote:
>:  Can you provide some evidence for this?  I've never heard of
>:any breakthrough science done by him.  I'm not convinced he had
>:any reputation whatsoever, good or bad, outside the scientific
>:community prior to his science popularization attempts.

>Well, let's see.  Sagan is the author of numerous scientific papers...

I know lots of people who have published numerous scientific papers,
but who have made no major breakthroughs, nor have any particular
reputation outside their own specialty. 

>...founded the largest professional journal for planetary science...

Actually, I think the Journal of Geophysical Research publishes
more planetary science papers than Icarus. In any case, founding
a journal is an organizational and administrative achievement, 
not a scientific one.

>...held positions at Cornell, JPL, and Caltech...

My first comment, above, applies to this as well: Holding
positions at three institutions, even two at institutions
that are quite prominent in planetary science, implies
neither major breakthroughs nor any reputation to speak of.

>...and was Principal Investigator on several NASA planetary 
>probe experiments...

Could you please be more specific? As far as I know, Sagan
has been a co-investigator or interdisciplinary scientist
on a number of missions, but never a principal investigator.
I can name a dozen people, off the top of my head, with 
similar experience. None of them have the reputation
Sagan has, so it looks like his reputation didn't come
from this aspect of his career.

                                                  Frank Crary
                                                  CU Boulder


From: fcrary@rintintin.Colorado.EDU (Frank Crary)
Newsgroups: sci.space.policy,sci.astro,alt.sci.planetary
Subject: Re: Colors of Io (Was:Re: Sagan (was Re: AAAS News Release! The 
	Details!! Signs of Past Life on Mars)):
Date: 13 Aug 1996 01:03:09 GMT

In article <4ulhoh$2le@infoserv.rug.ac.be>,
Filip De Vos <fidevos@eduserv1.rug.ac.be> wrote:
>: Have you actually read any of Sagan's papers? As far as I know, he
>: hasn't made any discoveries or predictions borne out by later data,
>: and his works include such gems as:
>[]
>: He identified the "colors" in the Voyager images of Io with high-temperature
>: 	alotropes of sulfur, despite the fact that those temperatures
>: 	are totally inconsistent with IR measurements and without
>: 	bothering the check about the details of the images. It
>: 	turns out that they aren't true color images (frames were
>: 	taken with the red, blue and violet filters and displayed
>: 	as red, green, blue.) 

>This is something I have noted about Io photographs: the pics released 
>shortly after the Voyager fly-bys showed Io in very bright colors 
>from Yellow over Red to Brown 'the planet like a pizza'. 

The initial ones at least. In (I think) the late 1980s, McEwen
made a best-guess correction to the true colors, by using
averages of the existing images through the various filters.

>The latest pictures I have seen, published just before Galileo was to 
>arrive at Jupiter, and presumably based on the same Voyager shots, show 
>much more subdued colors, more grays and browns. 

With the browns and darker greys mostly in the polar regions,
and the lighter greys/whites evenly distributed? That sounds
like McEwen's analysis.

>How _are (or have been) teh Voyager pictures color-corrected? 

See above. There was quite a bit of doubt about how accurate
those colors were, but the one Galileo image released so far
seems to confirm them.

>This brings to mind the first picture of the surface of Mars, taken by 
>Viking, that was wrongly mixed by technicians. The Viking carried a stand 
>with colors, that could be (and was) used to color-correct the photos. 
>(That _was recounted by Sagan, in his _Pale Blue Dot_ book)
>How is this done with Voyager and other interplanetary probes? 

It depends on the instrument. Mostly, I think they just check
the calibration and transmission of each filter before launch
and assume it won't change in flight. The instruments are
more modern than the Viking imager, so it's not as bad an
approach as it might sound given the Viking problem. Other
than that, Galileo has a big advantage: There is a big
campaign of Earth and Earth-orbit observations to enhance
the Galileo mission. Those images are _much_ easier to 
calibrate, and you could probably use the results to
both check the Galileo calibrations and provide additional,
scientific information. However, I don't know about all
the details. I _think_ PPR will be analyzed in this way
and I'm reasonably sure UVS/EUV will be. But neither of those
instruments is a visible light imager.

                                                 Frank Crary
                                                 CU Boulder



Newsgroups: sci.space.history
From: henry@spsystems.net (Henry Spencer)
Subject: Re: CARL SAGAN: POTHEAD
Date: Wed, 25 Aug 1999 13:46:50 GMT

In article <MPG.122d31e01350306f98983e@news.swcp.com>,
Russell Stewart <spamtrap2@yahoo.com> wrote:
>> I can't think of any professional scientists who are anything but
>> grateful for the popularizing efforts of people like Isaac Asimov and
>> Arthur C. Clarke.
>
>Of course. Asimov and Clarke were not professional scientists, so they
>were allowed to be popularizers. Sagan, OTOH, had a Ph.D. and did real
>research. Therefore, he was not. It's a ridiculous double-standard.

Asimov had a PhD, and was a professor at Boston University for his entire
working life (although after 1958 it was basically honorary).  He did even
do a bit of research, before he realized (by his own admission) that he
was no good at it.

I think much of the dislike for Sagan comes from the medium he chose:  TV
is a good way to reach lots of people, but a poor way to convey complex
ideas.  The level of oversimplification and dramatization needed to hold
viewers' attention is enough to bother professionals, and TV's emphasis on
the presenter rather than the material presented is strong enough to rouse
suspicions that it's being done for self-promotion rather than for
science.  Sagan's political agenda also made itself annoyingly obvious in
some of his later work (including some of his science).

There is no shortage of professional scientists doubling as popularizers
who have not provoked a fraction of the hostility people felt toward
Sagan.  Their popularizing activities often are not highly regarded, but
it doesn't extend to the scientists themselves being disliked.  Details
matter; Sagan was disliked because of the approach he took and the way he
did things, not because scientists hate scientist-popularizers in general.
--
The good old days                   |  Henry Spencer   henry@spsystems.net
weren't.                            |      (aka henry@zoo.toronto.edu)


Newsgroups: sci.space.history
From: henry@spsystems.net (Henry Spencer)
Subject: Re: 2001: And in the plus column .... ?
Date: Fri, 2 Feb 2001 15:29:54 GMT

In article <3a6c66fc.74428990@news.seanet.com>,
Derek Lyons <elde@hurricane.net> wrote:
>"Terrell Miller" <terrellmiller@mindspring.com> wrote:
>>actually, that theory is now in disfavor, kind of like nuclear winter...
>
>Huh?  Since when is nuclear winter in disfavor?  It's been well proven
>to be true, (if not quite as bad as Sagan et al predicted).

Sagan's oversimplified and biased model was thoroughly trashed soon after
it appeared, and likewise the severe predictions that resulted from it,
but the issue -- effects on climate of dust and smoke from a large-scale
nuclear war -- is real and serious, and had been largely overlooked until
Sagan et al made a fuss about it.
--
When failure is not an option, success  |  Henry Spencer   henry@spsystems.net
can get expensive.   -- Peter Stibrany  |      (aka henry@zoo.toronto.edu)

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