Sublimation: A Mechanism for the Enrichment of Organics in Antarctic IceRecent analyses of the carbonate globules present in the Martian meteorite ALH84001 have detected polycyclic aromatic hydrocarbons (PAHs) at the ppm level. The distribution of PAHs observed in ALH84001 was interpreted as being inconsistent with a terrestrial origin and were claimed to be indigenous to the meteorite, perhaps derived from an ancient Martian biota. However, Becker et al., have examined PAHs in the Martian meteorite EETA79001, in several Antarctic carbonaceous chondrites and Antarctic Allan Hills Ice and detected many of the same PAHs found in ALH84001. The reported presence of L-amino acids of apparent terrestrial origin in the EETA79001 druse material, suggests that this meteorite is contaminated with terrestrial/extraterrestrial organics probably derived from Antarctic ice meltwater that had percolated through the meteorite. The detection of PAHs and L-amino acids in these Martian meteorites suggests that despite storage in the Antarctic ice, selective changes of certain chemical and mineralogical phases has occurred.
Document ID
20020048255
Acquisition Source
Ames Research Center
Document Type
Conference Paper
Authors
Becker, Luann (Scripps Institution of Oceanography La Jolla, CA United States)
McDonald, Gene D. (Cornell Univ. Ithaca, NY United States)
Glavin, Daniel P. (Scripps Institution of Oceanography La Jolla, CA United States)
Bada, Jeffrey L. (Scripps Institution of Oceanography La Jolla, CA United States)
Bunch, Theodore E. (NASA Ames Research Center Moffett Field, CA United States)