Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA.
Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, USA.
Nature. 2023 Jul;619(7971):724-732. doi: 10.1038/s41586-023-06143-z. Epub 2023 Jul 12.
The presence and distribution of preserved organic matter on the surface of Mars can provide key information about the Martian carbon cycle and the potential of the planet to host life throughout its history. Several types of organic molecules have been previously detected in Martian meteorites and at Gale crater, Mars. Evaluating the diversity and detectability of organic matter elsewhere on Mars is important for understanding the extent and diversity of Martian surface processes and the potential availability of carbon sources. Here we report the detection of Raman and fluorescence spectra consistent with several species of aromatic organic molecules in the Máaz and Séítah formations within the Crater Floor sequences of Jezero crater, Mars. We report specific fluorescence-mineral associations consistent with many classes of organic molecules occurring in different spatial patterns within these compositionally distinct formations, potentially indicating different fates of carbon across environments. Our findings suggest there may be a diversity of aromatic molecules prevalent on the Martian surface, and these materials persist despite exposure to surface conditions. These potential organic molecules are largely found within minerals linked to aqueous processes, indicating that these processes may have had a key role in organic synthesis, transport or preservation.
火星表面保存的有机物的存在和分布可以提供有关火星碳循环的关键信息，以及火星在其历史上存在生命的潜力。以前在火星陨石和盖尔陨石坑中已经检测到几种类型的有机分子。评估火星其他地方有机物的多样性和可检测性对于了解火星表面过程的范围和多样性以及碳源的潜在可用性非常重要。在这里，我们报告了在火星杰泽罗陨石坑的陨石坑底部序列中的 Máaz 和 Séítah 地层中检测到与几种芳香族有机分子一致的拉曼和荧光光谱。我们报告了特定的荧光矿物组合，与不同空间模式下发生的许多类有机分子一致，这些有机分子可能表明不同环境中碳的命运不同。我们的研究结果表明，火星表面可能存在多种芳香族分子，而且这些材料在暴露于表面条件下仍然存在。这些潜在的有机分子主要存在于与水相过程相关的矿物中，这表明这些过程可能在有机合成、运输或保存中发挥了关键作用。
