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Environmental and Field Emission Scanning Electron Microscopy (ESEM and FESEM) investigations have
shown that a wide variety of carbonaceous meteorites contain the remains of large filaments embedded within
freshly fractured interior surfaces of the meteorite rock matrix. The filaments occur singly or in dense
assemblages and mats and are often encased within carbon-rich, electron transparent sheaths. Electron
Dispersive X-ray Spectroscopy (EDS) spot analysis and 2D X-Ray maps indicate the filaments rarely have
detectable nitrogen levels and exhibit elemental compositions consistent with that interpretation that of the
meteorite rock matrix. Many of the meteorite filaments are exceptionally well-preserved and show evidence
of cells, cell-wall constrictions and specialized cells and processes for reproduction, nitrogen fixation,
attachment and motility. Morphological and morphometric analyses permit many of the filaments to be
associated with morphotypes of known genera and species of known filamentous trichomic prokaryotes
(cyanobacteria and sulfur bacteria). The presence in carbonaceous meteorites of diagenetic breakdown
products of chlorophyll (pristane and phytane) along with indigenous and extraterrestrial chiral protein amino
acids, nucleobases and other life-critical biomolecules provides strong support to the hypothesis that these
filaments represent the remains of cyanobacteria and other microorganisms that grew on the meteorite parent
body. The absence of other life-critical biomolecules in the meteorites and the lack of detectable levels of
nitrogen indicate the filaments died long ago and can not possibly represent modern microbial contaminants
that entered the stones after they arrived on Earth. This paper presents new evidence for microfossils,
biomolecules and biominerals in carbonaceous meteorites and considers the implications to some of the major
hypotheses for the Origin of Life.
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