Life in Mars confirmed by NASA
jacob navia
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".
Jonathan Thornburg
Subject: Re: Life in Mars confirmed by NASA
Newsgroups: sci.astro.research
References: <mt2.0-4800...@hydra.herts.ac.uk>
jacob navia <ja...@nospam.org> wrote:
> 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
Ryan Anderson has an interesting discussion at
http://martianchronicles.wordpress.com/2009/12/01/life-on-mars/
which also includes links to the original research papers.
The authors of the latest claims are essentially the same group who
claimed to have found evidence for (past) life in the meteorite
ALH84001 back in 1996. My impression is that most of the planetary-
-science community remains unconvinced by that claim. So... part of
the reason for the lack of a more enthusiastic response to the latest
claims may be the "Boy Who Cried Wolf" effect. As Carl Sagan famously
said, "Extraordinary claims require extraordinary evidence."
In this context, claiming to have found evidence of life on Mars
(either past or present) is such a big (in the sense of "if it is
indeed true, it's a *big* discovery") claim that I think Sagan's rule
applies. It will be very interesting to see the responces to the
latest claims from other people working in the life-on-Mars area.
jacob navia <ja...@nospam.org> wrote:
> And when you read this material please remember:
>
> "There is no blinder person as the man that doesn't want to see".
Most astronomers & astrobiologists (myself included) would absolutely
*love* to see life on Mars confirmed! The detailed study of such life
would be, to put it mildly, of great scientific interest!
Or, if you want to just consider pure self-interest, such a discovery
would very likely lead to better job prospects for astronomers &
astrobiologists, and to boosts in funding for a wide variety of
planetary-science projects (including the NASA/ESA
plans-with-no-solid-funding-yet for a robotic Mars Sample Return
mission
http://futureplanets.blogspot.com/2009/12/new-mars-sample-return-plan.html
http://futureplanets.blogspot.com/2009/12/new-mars-sample-return-mission-part-two.html
to fly in ~2025).
But precisely because our natural biases run towards "yes", we need to
be skeptical to ferrit out the actual truth, uncontaminated by our natural
biases. In particular, in this context false positives are very damaging
to the credibility of all involved.
I think Ryan Anderson's closing paragraph sums things up nicely:
| So, what does it all mean? Is this evidence for life on Mars? I
| give it a definitive "maybe". It's clear that the debate is far
| from over, and I expect to see some interesting rebuttal papers in
| the next few years. There's a fine line to walk here. If this really
| is evidence of life on Mars, we should be shouting it from the
| rooftops! But it is so easy to trick ourselves into seeing what we
| want to see that we have to be cautious. Carl Sagan summed this up
| nicely: "Extraordinary claims require extraordinary evidence." Right
| now I think the evidence is not extraordinary, but it may be getting
| there.
--
-- "Jonathan Thornburg [remove -animal to reply]" <jth...@astro.indiana-zebra.edu>
Dept of Astronomy, Indiana University, Bloomington, Indiana, USA
"Washing one's hands of the conflict between the powerful and the
powerless means to side with the powerful, not to be neutral."
-- quote by Freire / poster by Oxfam
Kent Paul Dolan
> Life in Mars confirmed by NASA
Well, no.
> 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
The two main papers linked from that web page were a
very long read indeed, especially to someone with no
particular expertise in geochemistry.
> And when you read this material please remember:
> "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.
jacob navia
>
> Ryan Anderson has an interesting discussion at
> http://martianchronicles.wordpress.com/2009/12/01/life-on-mars/
> which also includes links to the original research papers.
>
> The authors of the latest claims are essentially the same group who
> claimed to have found evidence for (past) life in the meteorite
> ALH84001 back in 1996. My impression is that most of the planetary-
> -science community remains unconvinced by that claim. So... part of
> the reason for the lack of a more enthusiastic response to the latest
> claims may be the "Boy Who Cried Wolf" effect. As Carl Sagan famously
> said, "Extraordinary claims require extraordinary evidence."
>
> In this context, claiming to have found evidence of life on Mars
> (either past or present) is such a big (in the sense of "if it is
> indeed true, it's a *big* discovery") claim that I think Sagan's rule
> applies. It will be very interesting to see the responces to the
> latest claims from other people working in the life-on-Mars area.
>
Please, let's discuss the scientific arguments. Magnetite is a
sure sign of life. The people at NASA disprove the only counter-argument
advanced by the opponents to marsian life: an unorganic origin of the magnetite.
The authors from Johnson's space center disprove that. If you agree with the thesis of
the paper (and it will be difficult to disagree) then the origin of the
magnetite can only be biological!
If your "impression is that most of the planetary science
community remains unconvinced" that may be true, but it is not
a scientific argument. Science doesn't get done by opinion polls.
The authors say:
<quote>
The unique properties of these magnetites (elongated along the c-axis, single domain grain size,
extremely pure Fe oxide, tightly sorted grain size distribution) remains a suite of properties
absolutely unique to magnetotactic magnetites on Earth.
<end quote>
That is clear. And they prove that can't be contamination. So, life on mars is a
fact.
jacob navia
> jacob navia wrote:
>
> > Life in Mars confirmed by NASA
>
> Well, no.
>
> > 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
>
> The two main papers linked from that web page were a
> very long read indeed, especially to someone with no
> particular expertise in geochemistry.
>
> > And when you read this material please remember:
>
> > "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.
>
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.
> 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.
> 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.
> 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.
> 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.
> 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.
> 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.
> 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?
> 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?
> 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.
> 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
:-)
Kent Paul Dolan
[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.
Juergen Barsuhn
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)
Jonathan Thornburg [remove -animal to reply]
> 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?
I don't know (I'm not an expert in this area).
However, I do know that the transit time for a meteorite from Mars to
get to Earth is quite short -- typically only 10s of millions of years.
(This is predicted by celestial-mechanics simulations of meteorite
orbital dynamics, and confirmed by explicit measurements of the
cosmic ray exposures of these meteorites.) So ALH84001 (and the other
dozen-or-so Martian meteorites) only give us samples of the Martian
atmosphere from (geologically) present times. Alas, we know almost
nothing about what the Martian atmosphere was like billions of years
ago. :(
> 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.
Yes, this is a hard problem. My understanding (again with the
caveat that I'm emphatically not an expert in this area) is that the
researchers try rule out terrestrial contamination by looking at how
the purportedly--non-terrestrial features are distributed through the
volume of the meteorite: If they're more common towards the surface
or on fissures, that would argue for Earth-life contamination being
plausible. On the other hand, if the features are found even
"sealed" inside single mineral grains of non-porous material, and
are *not* preferentially found near the meteorite's surface or near
fissures, that would argue against Earth-life contamination as their
origin.
When amino acids have been found in other meteorites, one argument
that they were of extra-terrestrial origin was (is) that they're an
equal mixture of left- and right-handed stereo-isomers, whereas all
Earth life is left-handed. Of course, this argument only proves that
those amino acids didn't come from the Earth -- it doesn't say anything
about whether natural chemical processes could have produced them
elsewhere in the solar system (which is indeed what people who study
this say is by far the most likely hypothesis).
[Just to be clear, the arguments for and against ancient Martian life
traces in ALH84001 et al didn't involve amino acids; I don't think any
amino acides have been found in Martian meteorites.]
--
-- "Jonathan Thornburg [remove -animal to reply]" <jth...@astro.indiana-zebra.edu>
Dept of Astronomy, Indiana University, Bloomington, Indiana, USA
"Only one carry on? No electronics for the first hour of flight?
I wish that, just once, some terrorist would try something that
you can only foil by upgrading the passengers to first class and
giving them free drinks." -- Bruce Schneier