Search for past life on Mars: Possible relic biogenic activity in Martian meteorite ALH84001
Search for past life on Mars: Possible relic biogenic activity in Martian meteorite ALH84001
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DOI：
10.1126/science.273.5277.924
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发表时间：
1996-08-16
期刊：
影响因子：
56.9
通讯作者：
Zare, RN
中科院分区：
文献类型：
--
作者：
McKay, DS;Gibson, EK;Zare, RN
火星陨石 ALH84001 的新鲜断裂表面含有丰富的多环芳烃（PAH）。这些新的断裂表面也显示出碳酸盐球。污染研究表明多环芳烃是陨石固有的。对选定碳酸盐球的表面纹理和内部结构进行的高分辨率扫描和透射电子显微镜研究表明，这些球含有细粒的单畴磁铁矿和铁硫化物的第二相。碳酸盐球的结构和大小与一些陆地细菌引起的碳酸盐沉淀相似。尽管无机形成是可能的，但生物过程形成的小球可以解释许多观察到的特征，包括多环芳烃。因此，多环芳烃、碳酸盐球及其相关的次生矿物相和结构可能是过去火星生物群的化石遗迹。
Fresh fracture surfaces of the martian meteorite ALH84001 contain abundant polycyclic aromatic hydrocarbons (PAHs). These fresh fracture surfaces also display carbonate globules. Contamination studies suggest that the PAHs are indigenous to the meteorite. High-resolution scanning and transmission electron microscopy study of surface textures and internal structures of selected carbonate globules show that the globules contain fine-grained, secondary phases of single-domain magnetite and Fe-sulfides. The carbonate globules are similar in texture and size to some terrestrial bacterially induced carbonate precipitates. Although inorganic formation is possible, formation of the globules by biogenic processes could explain many of the observed features, including the PAHs. The PAHs, the carbonate globules, and their associated secondary mineral phases and textures could thus be fossil remains of a past martian biota.