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Extraterrestrial Lifeforms Found?

  1. Aug 10, 2004 #1


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    Cyanobacteria found in a meteorite:

    At a conference in Denver today [2 Aug 2004], NASA's Richard Hoover announced evidence of a fossilized cyanobacterial mat in the Orgueil carbonaceous meteorite. His pictures of forms in the meteorite were indistinguishable from known, Earthly fossilized cyanobacteria such as phormidium tenuissimum. The images from Orgueil were taken in July, 2004, using Environmental- and Field Emission Scanning Electron Microscopy at NASA's Marshall Space Flight Center in Huntsville, Alabama.

    Other fossilized bacteria have been found in meteorites, including Orgueil, before now (see related webpages linked [at panspermia.org website].) But the possibility that Earthly bacteria could have colonized the meteorites and left fossils in them after they arrived leaves room for doubt within the scientific establishment today. Contamination is not a possible cause now however, because the observed cyanobactera, on Earth, form their mats only under water on surfaces exposed to sunlight. This fragment of Orgueil was not under water on Earth (it would have dissolved), nor was its interior open and exposed to sunlight on Earth before now. Furthermore, the newly seen fossils are not isolated single cells, but whole ecologies. They must have grown on the meteorite's parent body before it fell.

    Participants at the SPIE Conference in Denver who saw the new images agreed that Hoover's evidence is momentous. Photos and updates will be posted here when available.

  2. jcsd
  3. Aug 10, 2004 #2


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    Staff: Mentor

    In light of the first two, I'm not buying the 3rd.
  4. Aug 10, 2004 #3


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    Thanks, I did not read it closely enough first time.
  5. Aug 11, 2004 #4
    May you please clarify why that statement is wrong? I'm not arguing, I just don't understand.
  6. Aug 12, 2004 #5
    Can the DNA of fossilized cyanobacteria be analized?
  7. Aug 12, 2004 #6


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    It's a bacteria found on Earth. Similar contamination has previously been found in this meteorite.

    The other part of the logic that doesn't make any sense is stating that this bacteria can only grow under water when exposed to sunlight, and then turning the argument to say that explains why it grew while the meteorite was somewhere else other than Earth. More likely, they've just found a form of this bacteria that can grow in a different place on Earth than previously recognized. It's rather unscientific to just say contamination is not possible too. There's always the possibility of contamination, and if this meteorite is of a composition that would dissolve upon exposure to water, then it would easily explain why a bacterial contamination inside it would leave what appear to be fossils even if they only recently made their way in (the water of the bacteria would have dissolved some of the mineral leaving an impression, like a footprint, of their presence).
  8. Aug 12, 2004 #7


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    Staff: Mentor

    To paraphrase,

    -The bacteria found look exactly like Earth bacteria (implying, maybe they are earth bacteria).

    -Fossillized earth bacteria have been found in other meteorites (supports the conclusion from the first fact that they are Earth bacteria).

    -The bacteria could not have originated from earth (implying that on Mars, there are bacteria identical to bacteria on earth - an extrordinary claim).

    So either there are bacteria on Mars identical to that on Earth, or the 3rd statement is wrong. I'd put my money on the 3rd statement being wrong.
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