On biogenicity criteria for endolithic microborings on early Earth and beyond

Micron-sized cavities created by the actions of rock-etching microorganisms known as euendoliths are explored as a biosignature for life on early Earth and perhaps Mars. Rock-dwelling organisms can tolerate extreme environmental stresses and are excellent candidates for the colonization of early Earth and planetary surfaces. Here, we give a brief overview of the fossil record of euendoliths in both sedimentary and volcanic rocks. We then review the current understanding of the controls upon the distribution of euendolithic microborings and use these to propose three lines of approach for testing their biogenicity: first, a geological setting that demonstrates a syngenetic origin for the euendolithic microborings; second, microboring morphologies and distributions that are suggestive of biogenic behavior and distinct from ambient inclusion trails; and third, elemental and isotopic evidence suggestive of biological processing. We use these criteria and the fossil record of terrestrial euendoliths to outline potential environments and techniques to search for endolithic microborings on Mars.     

Hazard Prevention in Mission Plans for Aerial Vehicles Based on Soft Institutions

Hazard prevention in mission plans requires careful analysis and appropriate tools to support the design of preventive and/or corrective measures. It is most challenging in systems with large sets of states and complex state relations. In the case of sociotechnical systems, hazard prevention becomes even more dicult given that the behaviour of human centric components can at best be partially predictable. In the present article we focus on a specic class of sociotechnical systems namely air spaces containing pilot controlled as well as autonomous aircrafts and introduce the notion of relevant hazards. We also introduce soft institutions as an appropriate basis for analysis, with the aim of addressing relevant hazards. The concept of soft institutions is drawn from specication languages for interaction between agents in multi agent systems but, in our case, is adapted for use in systems that combine human and automated actors.