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Posted by jacob navia on December 21, 2009, 4:12 am
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Using more advanced instruments, NASA reviews the evidence in marsian meteorites.
This was briefly mentioned last month. The news media did not give it the
importance
this news merits.
If you want to read the scientific papers, and see the electronic microscope
photographs please go to:
http://www.nasa.gov/centers/johnson/home/mars_meteorite.html
And when you read this material please remember:
"There is no blinder person as the man that doesn't want to see".
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Posted by Kent Paul Dolan on December 23, 2009, 7:20 am
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jacob navia wrote:
show/hide quoted text
> Life in Mars confirmed by NASA
Well, no.
show/hide quoted text
> Using more advanced instruments, NASA reviews the
> evidence in marsian meteorites. This was briefly
> mentioned last month. The news media did not give
> it the importance this news merits.
show/hide quoted text
> If you want to read the scientific papers, and see
> the electronic microscope photographs please go
> to:
show/hide quoted text
The two main papers linked from that web page were a
very long read indeed, especially to someone with no
particular expertise in geochemistry.
show/hide quoted text
> And when you read this material please remember:
show/hide quoted text
> "There is no blinder person as the man that
> doesn't want to see".
Pre-insulting anyone who disagrees with your
favored conclusions only raises hackles and
increases determination in those thus insulted
to find some way to oppose those conclusions.
The authors seemed to do a splendid job in detail of
demolishing arguments others had put forward earlier
against the authors' earlier speculations, and I'm
modestly persuaded by the pictures that the present
conclusions of "life once existed on Mars" may be
correct.
Well but, Mars is quite a different environment from
Earth, in particular the composition of its
atmosphere is mostly CO2 with only a trace of O2, in
particular, its mantle (and core) has cooled and
solidified resulting in different mineral types and
compositions there than in the molton mantle of
Earth, and so presumably the solid mantle of Mars
has very different impact chemistry when large
meteor excavations reach mantle-deep than does the
fluid mantle of Earth. It is thus perhaps
unreasonable to expect that large meteor impacts
produced the identical chemical results on Mars as
they have done on Earth.
In any case, stepping back a bit, the overall
argument forms these papers convey creates
great unhappiness.
They are, after all, purely arguments from
ignorance.
Consider the arguments of Genesis: we don't know a
natural mechanism by which the dry land, the great
waters, the sky, the heavens, and the abundant forms
of life on Earth were created.
Therefore, "goddidit".
Compare the arguments in the linked papers: we don't
know how the nanoscale carbonate disks and threads,
the very pure magnetite microcrystals, could
possibly be created by abiotic means.
Therefore, "lifedidit".
In both cases, some favorite evidence-free
hypothesis for the origin of observations in hand is
"confirmed" only by being unable to find alternative
solutions supported by existing evidence, yet there
are infinitely many favorite speculative alternative
hypotheses, equally evidence-free, that could just
as easily have been chosen to be declared as
"proved" by such a flawed argument style.
In each case, maybe waiting to see if a more
complicated but correct explanation could be found
would have been wise.
It is also more than a little depressing to think
that the universe, and chemistry, are so
unimaginative that "life on Mars" should be such a
dreary imitation of "life on Earth" that "pure
magnetite" would be a tool developed for use by
tiny organisms on each, that disks and threads
should be the shapes of discovered lifeforms on Mars
as they are on Earth.
Why did Mars life not shape itself into pentagons,
or dodecahedrons, or hollow rings, or fiber bundles?
Why did Mars life not use some diamagnetic or
gyroscopic steering mechanism?
Emotionally, this identity of developed mechanisms
used by life rather argues that "life on Earth" and
"life on Mars" arose from a single abiogenesis
event, developed for quite a while and to quite a
level of sophistication containing these common
mechanisms, and then traveled one way or the other
by meteor=borne cross-contamination.
That doesn't do much to remove the lingering
suspicion that "we are alone in the universe", now
amended with: "except for replications and
distributions of our own life chemistry and forms to
nearby worlds".
FWIW
xanthian.
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Posted by jacob navia on December 24, 2009, 3:45 am
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Kent Paul Dolan a écrit :
show/hide quoted text
Please, that statement means that you should read those papers with an
objective, scientific attitude, not at all as an insult.
Treating that as an insult starts the discussion in a polemic note
that is not justified.
show/hide quoted text
> The authors seemed to do a splendid job in detail of
> demolishing arguments others had put forward earlier
> against the authors' earlier speculations, and I'm
> modestly persuaded by the pictures that the present
> conclusions of "life once existed on Mars" may be
> correct.
OK.
show/hide quoted text
> Well but, Mars is quite a different environment from
> Earth, in particular the composition of its
> atmosphere is mostly CO2 with only a trace of O2, in
> particular, its mantle (and core) has cooled and
> solidified resulting in different mineral types and
> compositions there than in the molton mantle of
> Earth, and so presumably the solid mantle of Mars
> has very different impact chemistry when large
> meteor excavations reach mantle-deep than does the
> fluid mantle of Earth. It is thus perhaps
> unreasonable to expect that large meteor impacts
> produced the identical chemical results on Mars as
> they have done on Earth.
>
Sure. But that has nothing to do with biology.
show/hide quoted text
> In any case, stepping back a bit, the overall
> argument forms these papers convey creates
> great unhappiness.
>
> They are, after all, purely arguments from
> ignorance.
What else do you expect?
A detailed biochemical explanation based on marsian life biochemistry?
We do not know at all what kind of biochemistry marsian organisms have.
We know that each spring, methane is released TODAY by "unknown
processes", so the descendants of those organisms must be still around,
and in the near future we will be able to argue with more facts than
we have now.
show/hide quoted text
> Consider the arguments of Genesis: we don't know a
> natural mechanism by which the dry land, the great
> waters, the sky, the heavens, and the abundant forms
> of life on Earth were created.
>
> Therefore, "goddidit".
>
> Compare the arguments in the linked papers: we don't
> know how the nanoscale carbonate disks and threads,
> the very pure magnetite microcrystals, could
> possibly be created by abiotic means.
>
> Therefore, "lifedidit".
>
Excuse me but that is a preposterous argument. Magnetite findings, where
the chemical composition is similar to magnetite build by living
organisms on earth can't be compared with a religious "argument"
that exists only in some "holy" books. This is precisely trying
to argue without any scientific argument.
show/hide quoted text
> In both cases, some favorite evidence-free
> hypothesis for the origin of observations in hand is
> "confirmed" only by being unable to find alternative
> solutions supported by existing evidence, yet there
> are infinitely many favorite speculative alternative
> hypotheses, equally evidence-free, that could just
> as easily have been chosen to be declared as
> "proved" by such a flawed argument style.
>
If there are infinetely many, you should be able to name one...
The magnetite evidence, together with the photographs, together
with the methane emissions today, together with many other
observations give a consistent direction.
show/hide quoted text
> In each case, maybe waiting to see if a more
> complicated but correct explanation could be found
> would have been wise.
>
Why a more complicated explanation would be more correct?
This shows just an "apriori" against the life hypothesis.
show/hide quoted text
> It is also more than a little depressing to think
> that the universe, and chemistry, are so
> unimaginative that "life on Mars" should be such a
> dreary imitation of "life on Earth" that "pure
> magnetite" would be a tool developed for use by
> tiny organisms on each, that disks and threads
> should be the shapes of discovered lifeforms on Mars
> as they are on Earth.
>
This is a philosophical answer. You do not like the idea
of marsian organisms should use similar solutions to detect a
magnetic field than organisms on earth. Because...
Well yes, because
is also more than a little depressing to think
that the universe, and chemistry, are so unimaginative
But if you agree that the laws of physics are the same here and
there, that iron is very abundant both here and there WHY it should
be different?
show/hide quoted text
> Why did Mars life not shape itself into pentagons,
> or dodecahedrons, or hollow rings, or fiber bundles?
> Why did Mars life not use some diamagnetic or
> gyroscopic steering mechanism?
>
Who knows?
Maybe both forms of life have the same origin?
show/hide quoted text
> Emotionally, this identity of developed mechanisms
> used by life rather argues that "life on Earth" and
> "life on Mars" arose from a single abiogenesis
> event, developed for quite a while and to quite a
> level of sophistication containing these common
> mechanisms, and then traveled one way or the other
> by meteor=borne cross-contamination.
>
Maybe.
We have no data to prove or disprove that hypothesis.
show/hide quoted text
> That doesn't do much to remove the lingering
> suspicion that "we are alone in the universe", now
> amended with: "except for replications and
> distributions of our own life chemistry and forms to
> nearby worlds".
>
> FWIW
>
> xanthian.
When NASA takes us to the next star, we will be able to know
for sure
:-)
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Posted by Kent Paul Dolan on December 27, 2009, 2:46 pm
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jacob navia wrote:
[snipped in toto, see prior posting]
You gave nothing persuasive, sufficiently countering
to my prior statements, sufficiently indicating that
you had even considered my prior statements before
responding, or worthy of detailed response.
In general, yours was the "true believer" response.
I don't think that's a useful way to do or to
evaluate science.
This conversation is terminated, at least from my
end.
xanthian.
I'm compelled to answer one strange query from you,
though:
in the case of producing the explanation of the
origin of the universe from a knowledge base of
pure ignorance, "god did it" can as easily be
replaced by "krishna did it" or "the tribe ancestors
did it",
and in the case of your meteorites, "life did it"
can as easily be replaced by "advanced purpose
designed abiotic nanotechnology did it", by "magic
did it", or by "fred did it.
Arguments from ignorance are _worthless_ in exact
particular because they provide NO differentiation
between explanations for the area where ignorance
prevails, so that absolutely _any_ bogus
explanation can be stuffed into the gap left by
ignorance to replace the unexplained causations.
That's why such arguments are unacceptable as
science.
Proving all the ways something _couldn't_ have
happened is not a way of proving how it _did_
happen, because the explanations of how it did
happen are potentially uncountably infinite,
removing any possibility that the effort of
disproving them one by one will ever terminate.
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Posted by Juergen Barsuhn on January 5, 2010, 4:06 am
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I cannot introduce new arguments to the previous dispute
which at least appears to be interrupted. Rather I would
like to take this oppurtunity to update what I have learnt
so far on meteorites from Mars - to a large part in this
newsgroup and especially by J Th more than 5 years ago.
I learnt that tha Martian origin of the meteorite ALH84001
and others is derived from isotope ratios in small gas
buubles contained in the meteorites. These ratios were
different from those in other meteorites but consistent with
the atmospheric isotope ratios found by the Viking landers
in 1976 and 77. Since those days several new instruments
have been landed on Mars in different regions (Pathfinder
with Sojourner, the two rovers Spirit and Opportunity,
Phoenix) supplying new and probably more accurate data on
the atmosphere of Mars. Do the new results support the
Martian origin of these meteorites?
If ALH84001 wears signs of ancient microbial life on Mars,
it might originate from a wet past with a denser
atmosphere, i.e. an environment more friendly for life than
present. On the other hand, if the observed isotope ratios
are those of the present atmosphere, doesn't this support
the assumption that the atmosphere in the past was
essentially the same as today? Moreover, a grazingly
incident meteorite would probably fail to expedit a chunk of
surface matter into space through a dense atmosphere. Even
if sucessful, the chunk should be thoroughly molten thereby
destroying any delicate signatures of life. The situation is
different, if the meteorites result from catastrophic
impacts like that giving rise to the Hellas Basin.
Let us now consider the piece of Martian soil or regolith
that landed in Antarctica. How sure can we be that
terestrial microbes do not find their way into its interiar
through narrow fissures, producing those signstures that
have later on be found inside the meteorite in the
laboratory? Life is everywhere on Earth, and if the first
microbial "attack" failed, there would be sufficient time
for many more trials.
I would be grateful for any comments and/or links to more
information.
All the best Jurgen (Barsuhn)
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