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University of Technology of Compiègne, France

Pelton J.,International Space University
IEEE Communications Magazine | Year: 2010

The article following is perhaps unique among the many papers published thus far in this column. It covers not only the development of some of the technology required to turn the dream of commercial satellite communications into reality, but describes the policy decisions and politics involved in making this happen in the United States and elsewhere in the world as well. Policy questions raised and discussed include, first, the question of whether satellite communications in the United States should be government-run or a commercial enterprise; followed by the issue of how control should be manifested in international communication satellites. These policy questions in modern times are probably unique to satellite communication systems. Joe Pelton, the author, is well positioned to write an account of the early days of satellite communications in all of its ramifications, in both the policy and technical areas, having been present and working at Comsat Corporation, as well as later at Intelsat, during much of the period under discussion. We plan to follow this article with one focusing more on the communication technologies developed at Comsat during the early days of satellite communications. That article will be written by one of the engineers working at Comsat at the time. In the meantime, I am sure all readers will enjoy this article. Note that a number of readers of previous articles in this column have responded with letters to the editor commenting on, or expanding on, those articles. We urge you to send in your comments and or/questions about this article or any of the earlier articles as well. © 2010 IEEE. Source

Baarsen B.V.,University Medical Center mc | Baarsen B.V.,International Space University
Acta Astronautica | Year: 2013

The present study aims to explore the influence of person autonomy and voluntariness on the level and orientation of motivation and decision making of crew members who live and work in extreme isolated conditions such as during long-term space flights. Motivation has been related to positive behavioural (e.g., goal-orientation), cognitive (e.g., attention), and psychological (e.g., well-being) outcomes and is likely to be relevant for safe and favourable extraterrestrial life- and working-conditions. The study has been carried out within the scope of the Mars500 study which includes a Mars mission simulation of 105 (pilot study) and 520 (main study) days and involves a multi-national crew of 6 men who lived and worked in hermetically sealed modules in the IBMP facilities in Moscow. Data have been collected by the use of questionnaires that evaluate the Mars experiment in terms of, e.g. information received (e.g., My experiences here are in line with what I was told during the selection and instruction procedure),perceived social pressure (e.g., I don't feel free to make my own decisions), andpersonal challenge (e.g., I think that joining the first Mars mission would be a major challenge for me). It is hypothesised that stronger (1) perceived information consistency, (2) personal expectation consistency, (3) perceived voluntariness, and (4) experienced freedom of choice will be indicative of higher motivation levels. The results will be interpreted in the light of communication, decision making processes, and mission safety. Also, moral expectations and ethical considerations regarding future participation in long duration Human missions such as Mars will be discussed. We will make use of descriptive, longitudinal pattern analyses and correlations. © 2013 IAA Published by Elsevier Ltd. All rights reserved. Source

Clement G.,International Space University | Clement G.,Lyon Neuroscience Research Center | Wood S.J.,Azusa Pacific University
PLoS ONE | Year: 2014

The central nervous system must resolve the ambiguity of inertial motion sensory cues in order to derive an accurate representation of spatial orientation. Adaptive changes during spaceflight in how the brain integrates vestibular cues with other sensory information can lead to impaired movement coordination, vertigo, spatial disorientation, and perceptual illusions after return to Earth. The purpose of this study was to compare tilt and translation motion perception in astronauts before and after returning from spaceflight. We hypothesized that these stimuli would be the most ambiguous in the lowfrequency range (i.e., at about 0.3 Hz) where the linear acceleration can be interpreted either as a translation or as a tilt relative to gravity. Verbal reports were obtained in eleven astronauts tested using a motion-based tilt-translation device and a variable radius centrifuge before and after flying for two weeks on board the Space Shuttle. Consistent with previous studies, roll tilt perception was overestimated shortly after spaceflight and then recovered with 1-2 days. During dynamic linear acceleration (0.15-0.6 Hz, 61.7 m/s2) perception of translation was also overestimated immediately after flight. Recovery to baseline was observed after 2 days for lateral translation and 8 days for fore-aft translation. These results suggest that there was a shift in the frequency dynamic of tilt-translation motion perception after adaptation to weightlessness. These results have implications for manual control during landing of a space vehicle after exposure to microgravity, as it will be the case for human asteroid and Mars missions. Copyright: © 2014 Zhou et al. Source

Agency: Cordis | Branch: FP7 | Program: CSA-SA | Phase: SPA.2009.2.4.01 | Award Amount: 741.07K | Year: 2010

The general objective of the current project is to create the necessary conditions for utilizing the existing and emerging potential of the consortium partners in Nordic-Baltic dimension for continuous and sustainable contribution in major on-going and planned European space programmes. There is urgent need in emerging space countries for national space programme. For emerging space countries it could be primarily financed by the ESA PECS Charter but also by key governmental agencies. The NordicBaltSat has mission-oriented approach to build a bridge for successful integration into space industry in Europe. As a result of this project and as an overall impact emerging space countries are expected to raise their space capacities in order to access to ESA and to have contribution to European space programmes in future. There are several specific actions contributing to achieve the objectives of the project. The main actions intend to chart space potential and create joint technology programme; to build capacity and develop cooperation between emerging space countries and ESA; and to shape national space governance systems in emerging space countries. The activities include also dissemination and exploitation. These actions will enhance the potential of FP7 States to make a continuous and sustainable contribution to major on-going and planned European space programs. Capacity building and cooperation promotion between emerging space countries and ESA will strengthen the relationship with ESA and it also gives opportunity for future cooperation and adhesion to ESA. The actions will foster dialogue and debate on space science and research with the public beyond the research community, aiming at embracing a new generation of scientists and engineers.

Clement G.,International Space University | Ngo-Anh J.T.,European Space Agency
European Journal of Applied Physiology | Year: 2013

Experiments performed in orbit on the central nervous system have focused on the control of posture, eye movements, spatial orientation, as well as cognitive processes, such as three-dimensional visual perception and mental representation of space. Brain activity has also been recorded during and immediately after space flight for evaluating the changes in brain structure activation during tasks involving perception, attention, memory, decision, and action. Recent ground-based studies brought evidence that the inputs from the neurovestibular system also participate in orthostatic intolerance. It is, therefore, important to revisit the flight data of neuroscience studies in the light of new models of integrative physiology. The outcomes of this exercise will increase our knowledge on the adaptation of body functions to changing gravitational environment, vestibular disorders, aging, and our approach towards more effective countermeasures during human space flight and planetary exploration. © 2012 Springer-Verlag Berlin Heidelberg. Source

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