No abstract

The oceans cover more than two-thirds of the planet, representing the vastest part of natural resources. Nevertheless, only a fraction of the ocean depths has been explored. Within this context, this article presents the H2020 ENDURUNS project that describes a novel scientific and technological approach for prolonged underwater autonomous operations of seabed survey activities, either in the deep ocean or in coastal areas. The proposed approach combines a hybrid Autonomous Underwater Vehicle capable of moving using either thrusters or as a sea glider, combined with an Unmanned Surface Vehicle equipped with satellite communication facilities for interaction with a land station. Both vehicles are equipped with energy packs that combine hydrogen fuel cells and Li-ion batteries to provide extended duration of the survey operations. The Unmanned Surface Vehicle employs photovoltaic panels to increase the autonomy of the vehicle. Since these missions generate a large amount of data, both vehicles are equipped with onboard Central Processing units capable of executing data analysis and compression algorithms for the semantic classification and transmission of the acquired data.

This review focuses on advanced materials already used and suitable for application in (future) lunar extravehicular activity space suits. A historical and current literature/market survey is presented. Different functional layers of an astronaut garment are defined with emphasis on the external layers subjected to abrasive action of lunar regolith and degradation via exposure to space radiation/vacuum environment. Requirements are defined that would need to be fulfilled by these layers and suitable materials candidates are reviewed based on their key properties, including mechanical durability. Smart materials, combining additional functionalities, such as garment health monitoring, are also considered. The lead topic is the subject of an ongoing ESA‐funded research activity.

Microbial aerosols can be used as model particles for examining the dispersion and deposition of particles as well as assessing the reliability of the simulation methods. For example, the computational fluid dynamics model (CFD) can be used in the evaluation of indoor microbial contamination and the possible spread of harmful microbes in spaces with high densities of people or in special hermetic environments. The aim of this study was to compare the results of the CFD simulation, which predicts the deposition of biological particles on the surfaces of a spacecraft, and real particle deposition, using Bacillus licheniformis/aerius bacterium particles as the model organism. The results showed that the particles were mainly deposited on floor surfaces, but also onto the supply air diffusers, where bacterial concentrations were higher than on the wall and ceiling surfaces. The CFD simulation showed similar trends with actual particle dispersal, conducted in this experiment with Bacillus particles.