PLANETARY PROTECTION GUIDELINES FOR OUTER PLANET MISSIONS

Author(s):  
P. Stabekis ◽  
D.L. DeVincenzi
2017 ◽  
Vol 51 (4) ◽  
pp. 52-58
Author(s):  
E.A. Deshevaya ◽  
◽  
N.M. Khamidullina ◽  
A.A. Guridov ◽  
D.V. Zakharenko ◽  
...  
Keyword(s):  

2021 ◽  
Vol 22 (2) ◽  
pp. 647
Author(s):  
Jelena Vukalović ◽  
Jelena B. Maljković ◽  
Karoly Tökési ◽  
Branko Predojević ◽  
Bratislav P. Marinković

Electron interaction with methane molecule and accurate determination of its elastic cross-section is a demanding task for both experimental and theoretical standpoints and relevant for our better understanding of the processes in Earth’s and Solar outer planet atmospheres, the greenhouse effect or in plasma physics applications like vapor deposition, complex plasma-wall interactions and edge plasma regions of Tokamak. Methane can serve as a test molecule for advancing novel electron-molecule collision theories. We present a combined experimental and theoretical study of the elastic electron differential cross-section from methane molecule, as well as integral and momentum transfer cross-sections in the intermediate energy range (50–300 eV). The experimental setup, based on a crossed beam technique, comprising of an electron gun, a single capillary gas needle and detection system with a channeltron is used in the measurements. The absolute values for cross-sections are obtained by relative-flow method, using argon as a reference. Theoretical results are acquired using two approximations: simple sum of individual atomic cross-sections and the other with molecular effect taken into the account.


2019 ◽  
Vol 95 (10) ◽  
Author(s):  
Jose V Lopez ◽  
Raquel S Peixoto ◽  
Alexandre S Rosado

ABSTRACT Based on modern microbiology, we propose a major revision in current space exploration philosophy and planetary protection policy, especially regarding microorganisms in space. Mainly, microbial introduction should not be considered accidental but inevitable. We hypothesize the near impossibility of exploring new planets without carrying and/or delivering any microbial travelers. In addition, although we highlight the importance of controlling and tracking such contaminations—to explore the existence of extraterrestrial microorganisms—we also believe that we must discuss the role of microbes as primary colonists and assets, rather than serendipitous accidents, for future plans of extraterrestrial colonization. This paradigm shift stems partly from the overwhelming evidence of microorganisms’ diverse roles in sustaining life on Earth, such as symbioses and ecosystem services (decomposition, atmosphere effects, nitrogen fixation, etc.). Therefore, we propose a framework for new discussion based on the scientific implications of future colonization and terraforming: (i) focus on methods to track and avoid accidental delivery of Earth's harmful microorganisms and genes to extraterrestrial areas; (ii) begin a rigorous program to develop and explore ‘Proactive Inoculation Protocols’. We outline a rationale and solicit feedback to drive a public and private research agenda that optimizes diverse organisms for potential space colonization.


2014 ◽  
Vol 53 (7) ◽  
pp. 1135-1142 ◽  
Author(s):  
Yoshinori Takano ◽  
Hajime Yano ◽  
Yasuhito Sekine ◽  
Ryu Funase ◽  
Ken Takai

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