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“岩石生源论”提供实验数据，即微生物通过陨石在类地行星之间可行的运输。在这种情况下，微生物必须应对三个主要步骤：(i)通过撞击喷射逃离地球，（ii）长时间穿越太空，（iii）降落在另一个星球上。虽然在空间实验中已对该设想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生存能力的数据有限。在爆炸装置的冲击恢复实验中，耐药微生物测试系统…将有系统地受到一系列冲击压力（10- 45gpa），这是火星陨石所指示的范围，可以假定也适用于“地球”陨石。恢复后，实际的冲击压力将由受冲击矿物和主岩石的折射率测量来确定，或矿物成分石英和斜长石的精确校准数据可用。生物系统的活力将被量化，损害的种类和程度将被确定。

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.