[meteorite-list] New evidence for microbial fossils in Martian meteorite

From: Jason Phillips <jnbran_at_meteoritecentral.com>
Date: Fri, 7 May 2010 18:05:44 -0700 (PDT)
Message-ID: <442800.63733.qm_at_web45112.mail.sp1.yahoo.com>

Hello Robert and List,
That is my thoughts exactly Robert, I think we often overlook just what we have in our collections in the way of a piece of the planet Mars, wow how blessed we are.

Take Care,
Jason



--- On Thu, 5/6/10, Robert Verish <bolidechaser at yahoo.com> wrote:

> From: Robert Verish <bolidechaser at yahoo.com>
> Subject: [meteorite-list] Re: New evidence for microbial fossils in Martian meteorite
> To: "Meteorite-list Meteoritecentral" <meteorite-list at meteoritecentral.com>
> Date: Thursday, May 6, 2010, 12:58 PM
> Hello List,
>
> Whatever your opinion is on this subject, I'm sure we can
> all agree on this one thing - and that one thing was
> well-stated by McKay himself and was quoted in the last
> paragraph of that recent article.? Here it is:
>
> ----------------- Attached Text -------------------
> In a plenary session, in which Squyres solicited the
> group's views on
> how the field should move forward, McKay stood up to say
> that examining
> possible Martian microfossils should be a much higher
> priority. He said
> that the "biomorphs" now being found could answer some of
> the basic
> questions about life on Mars and that it could be done at a
> much lower
> cost than the multibillion-dollar alternative plan --
> sending a rover to
> Mars to pick up some rock samples and bringing them back to
> Earth.
>
> "These meteorites are samples from Mars," he said, "and
> need to be
> treated as the valuable resource they are."
> -------------------------------------------
>
> These are my sentiments, as well.
> Bob V.
>
>
> ----------------------- Attached Message
> --------------------
> [meteorite-list] NASA Team Cites New Evidence That
> Meteorites From Mars Contain Ancient Fossils
> Ron Baalke baalke at zagami.jpl.nasa.gov
> Wed May 5 18:53:16 EDT 2010
>
>
> http://www.washingtonpost.com/wp-dyn/content/article/2010/04/30/AR2010043002000.html
>
> NASA team cites new evidence that meteorites from Mars
> contain ancient fossils
>
> By Marc Kaufman
> Washington Post
> May 4, 2010
>
> LEAGUE CITY, TEX. -- NASA's Mars Meteorite Research Team
> reopened a
> 14-year-old controversy on extraterrestrial life last week,
> reaffirming
> and offering support for its widely challenged assertion
> that a
> 4-billion-year-old meteorite that landed thousands of years
> ago on
> Antarctica shows evidence of microscopic life on Mars.
>
> In addition to presenting research that they said disproved
> some of
> their critics, the scientists reported that additional
> Martian
> meteorites appear to house distinct and identifiable
> microbial fossils
> that point even more strongly to the existence of life.
>
> "We feel more confident than ever that Mars probably once
> was, and maybe
> still is, home to life," team leader David McKay said at a
> NASA-sponsored conference on astrobiology.
>
> The researchers' presentations were not met with any of the
> excited
> frenzy that greeted the original 1996 announcement about
> the meteorite
> -- which led to a televised statement by President Bill
> Clinton in which
> he announced a "space summit," the formation of a
> commission to examine
> its implications and the birth of a NASA-funded
> astrobiology program.
>
> Fourteen years of relentless criticism have turned many
> scientists
> against the McKay results, and the Mars meteorite
> "discovery" has
> remained an unresolved and somewhat awkward issue. This has
> continued
> even though the team's central finding -- that Mars once
> had living
> creatures -- has gained broad acceptance among the
> biologists, chemists,
> geologists, astronomers and other scientists who make up
> the
> astrobiology community.
>
> Speaking at a four-day conference near NASA's Johnson Space
> Center,
> McKay's team didn't claim it had definitive proof that the
> meteorites
> they are studying -- which can be identified as Martian
> because the
> gases inside them match the Martian atmosphere -- contain
> the remains of
> living organisms. Rather, the researchers described their
> re-energized
> confidence as emerging from a process of nitty-gritty
> science, based on
> inference, simulated testing and a kind of interplanetary
> forensics.
>
> McKay cited years of work by team members Kathie
> Thomas-Keprta and Simon
> Clemett that he said rebuts a central critique of the
> meteorite's
> significance. He also pointed to the presence of what
> appear to be
> fossilized microbes in other Martian meteorites, as well as
> the steady
> flow of discoveries by others pointing to a Mars that at
> one time could
> have supported life -- wet, warmer and enveloped in a
> potentially
> protective atmosphere and a magnetic field.
>
> Rebutting the critics
>
> The Thomas-Keprta work, published late last year in the
> journal
> Geochemica, centers on the origin of iron-based crystals
> called
> magnetites in the original Mars meteorite, called ALH84001.
> Magnetites
> on Earth are sometimes created by bacteria that respond to
> the planet's
> magnetic field; the McKay team argued that some of the
> Martian
> magnetites were of this biologically created type.
>
> Critics had said that the magnetites could have just as
> easily existed
> without bacteria or biology -- that they sometimes form as
> a result of
> the shock and searing heat that could come, for instance,
> from an
> asteroid strike. But in the recent paper, Thomas-Keprta, an
> expert in
> the use of electron beam technology to look inside rocks,
> reported that
> the purity of the magnetites made that explanation
> impossible.
>
> Reflecting both the contentiousness and drama of the
> debate,
> Thomas-Keprta finished her talk by referring to a recent
> article in a
> science journal that said the astrobiology community had
> "mostly
> abandoned" the biological explanations for the makeup of
> ALH84001. Her
> retort: "As Mark Twain put it, 'Reports of our death have
> been greatly
> exaggerated.' "
>
> McKay complained that not enough attention had been paid to
> work such as
> Thomas-Keprta's.
>
> "All the criticisms of our original paper got widely
> distributed, but
> when we did the work to prove the critics were wrong, it
> hardly made a
> ripple," he said at a conference interview. "We're now in a
> position to
> say we've knocked down all the criticisms -- and our
> biological
> explanation is the one left standing."
>
> Mary Voytek, director of NASA's astrobiology program,
> praised McKay and
> his team for their continued research into Mars meteorites,
> saying they
> have been crucial to the field.
>
> She said, however, that the astrobiology community as a
> whole remained
> unconvinced of their findings, in part because "the bar is
> so high." She
> also said it was still not proved that any possible
> microfossils on the
> meteorites had come from Mars, rather than forming as
> contaminants after
> the meteorites landed on Earth. In addition, all the
> Martian meteorites
> consist of hard igneous rock; the more fragile sedimentary
> rock, which
> is most likely to contain sign of life, falls apart before
> reaching Earth.
>
> Strong feelings
>
> Because the stakes involved with any announcement of
> possible or likely
> extraterrestrial life are so high -- both for science and
> for the
> societal and religious implications of such a discovery --
> the issue
> brings out very strong feelings. At the conference, a
> leading cautionary
> voice in astrobiology proposed that a special protocol be
> established to
> oversee release of any journal articles making dramatic
> extraterrestrial
> claims.
>
> Andrew Steele, of the Carnegie Institution for Science in
> Washington and
> once a member of the McKay team, compared the absence of
> astrobiology
> review with the formal procedures set up by scientists
> involved with the
> search for extraterrestrial life, or SETI.
>
> He said that SETI leaders understood the societal
> sensitivity of their
> work and that it was time for researchers in astrobiology
> "grow up and
> do the same."
>
> Astrobiology is the relatively new field of science that
> both searches
> for and tries to understand life beyond Earth, as well as
> how life began
> on Earth. The biennial conference attracted more than 700
> microbiologists, chemists, geologists, astronomers,
> geochemists and
> other researchers drawn into what might be science's most
> interdisciplinary field.
>
> Even as scientists debate McKay's assertions, the field has
> become
> increasingly optimistic about the possibility of finding
> remains (or
> perhaps even samples) of microbial life on Mars. Scores of
> papers
> presented during the conference supported the view that the
> now dry and
> frigid planet once was warm, wet and seemingly quite
> habitable.
>
> For instance, NASA planetary scientist Carol Stoker said
> that NASA's
> Phoenix lander -- which touched down near the Martian north
> polar region
> in 2008 -- found conditions that were harsh but even today
> suitable for
> life. Stoker, who was a co-investigator for several
> instruments on the
> Phoenix, said that data sent back met predetermined
> criteria that would
> indicate that the area could have supported Martian life
> even in recent
> times.
>
> Steven Squyres, another top scientist with extensive
> knowledge of Mars,
> said that he, too, is convinced that Mars once had
> conditions that could
> support life.
>
> The principal investigator for the two NASA rovers, Spirit
> and
> Opportunity, that have traveled Mars for the past six
> years, Squyres
> said that Mars once had water at or near the surface, now
> has many
> minerals that can be formed only in the presence of water
> and even had
> springs that once produced hot water and steam.
>
> "These are all things that lead to local habitable niches,"
> he said.
> "When you have the evidence right there in front of you
> for
> habitability, it makes a convincing case that you better go
> out and see
> if anyone lived out there."
>
> In a plenary session, in which Squyres solicited the
> group's views on
> how the field should move forward, McKay stood up to say
> that examining
> possible Martian microfossils should be a much higher
> priority. He said
> that the "biomorphs" now being found could answer some of
> the basic
> questions about life on Mars and that it could be done at a
> much lower
> cost than the multibillion-dollar alternative plan --
> sending a rover to
> Mars to pick up some rock samples and bringing them back to
> Earth.
>
> "These meteorites are samples from Mars," he said, "and
> need to be
> treated as the valuable resource they are."
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Received on Fri 07 May 2010 09:05:44 PM PDT