Experimental study of the survival of endolithic microorganisms during impact and ejection of Martian meteorites: First phase of the transfer of life between Mars and Earth

拟议项目的目的是为讨论“石胚说”提供实验数据，即通过陨石在类地行星之间可行地运送微生物。在这种情况下，微生物必须科普三个主要步骤：（i）通过撞击弹射逃离行星，（ii）在较长时间内穿越太空，以及（iii）降落在另一颗行星上。虽然在空间实验中对设想方案的第二步进行了深入研究，但关于第一步即撞击弹射的微生物存活能力的数据有限。在爆炸装置的冲击恢复实验中，耐微生物测试系统...将有系统地受到一系列冲击压力（10-45 GPa），这些压力在火星陨石所指示的范围内，可以假定也适用于“地球”陨石。回收后，实际冲击压力将通过测量受冲击矿物和寄主岩石或矿物成分石英和斜长石的折射率来确定，这些矿物成分有准确的校准数据。将对生物系统的活力进行量化，并确定损害的种类和程度。

It is the aim of the proposed project to provide experimental data to the discussion of "lithopanspermia", i.e. the viable transport of microorganisms between the terrestrial planets by means of meteorites. In this scenario, the microorganisms have to cope with three major steps: (i) escape from the planet by impact ejection, (ii) journey through space over extended time periods, and (iii) landing on another planet. Whereas step two of the scenario has been studied in depth in space experiments, there are only limited data on the survivability of microorganisms of the first step, i.e. impact ejection. In shock recovery experiments with an explosive set-up, resistant microbial test systems... will be systematically subjected to a series of shock pressures (10-45 GPa) which are in the range indicated by the Martian meteorites and which can be assumed to hold also for "Earth" meteorites. After recovery, the actual shock pressure will be determined by refractive index measurements of the shocked mineral and host rock' or mineral components quartz ad plagioclase for which accurate calibration data are available. The vitality of the biological systems will be quantified and the kind and degree of damage will be identified.