Space Radiation Biology

Space Radiation Biology and Related Topics provides information pertinent to the fundamental aspects of space radiation biology. This book discusses space radiation hazards as well as the importance of natural radiations in the processes of biogenesis. Organized into 12 chapters, this book begins with an overview of the fundamental aspects of radiobiology. This text then discusses the theoretical treatments of the chronic radiation response and the applicability of some of its features in extended manned space missions. Other chapters review the literature on models for recovery from radiation damage to some cellular systems. This book discusses as well the effects of radiations on mammals, with emphasis on those effects pertinent to the space-flight situation. The final chapter deals with the safety of nuclear power in space and explains the three types of nuclear devices designed for power production in space. This book is a valuable resource for radiologists, radiobiologists, and radiotherapists.

This volume is based on the proceedings of an Advanced Study Institute (ASI) sponsored by the North Atlantic Treaty Organization (NATO) held October 1987 in Corfu, Greece. The Institute received financial support from the National Aeronautics and Space Administration, U.S.A. Armed Forces Radiobiology Research Institute, U.S.A. Department of Energy, U.S.A. Deutsche Forschungs-und Versuchanstalt fur Luft und Raumfahrt e.v., Kaln, Germany The advent of the shuttle era is providing fresh impetus for large space ventures such as communication centers, solar power stations, astronomical observatories, orbiting factories, and space based radar. Such ventures will rely heavily on an extensive and prolonged human presence in space doing in-orbit construction, maintenance, and opera tion. Among the advantages of location in space are the near zero gravity environment, commanding location, and the reception of solar energy and astronomical signals unattenuated by the atmosphere. Central to long-term manned space missions are the problems associated with the effects of exposure to ionizing radiations on humans. Manned space mis sions in the past have encountered relatively benign radiation environ ments because of their very short duration and orbit configuration. However, crew stay time of up to a year has been recently achieved by the Soviet space program; and Mars missions lasting several years are under serious consideration.

This volume of the series Springer Briefs in Space Life Sciences explains the physics and biology of radiation in space, defines various forms of cosmic radiation and their dosimetry, and presents a range of exposure scenarios. It also discusses the effects of radiation on human health and describes the molecular mechanisms of heavy charged particles’ deleterious effects in the body. Lastly, it discusses countermeasures and addresses the vital question: Are we ready for launch? Written for researchers in the space life sciences and space biomedicine, and for master’s students in biology, physics, and medicine, the book will also benefit all non-experts endeavouring to understand and enter space.

Space missions subject human beings or any other target of a spacecraft to a radiation environment of an intensity and composition not available on earth. Whereas for missions in low earth orbit (LEO), such as those using the Space Shuttle or Space Station scenario, radiation exposure guidelines have been developed and have been adopted by spacefaring agencies, for exploratory class missions that will take the space travellers outside the protective confines of the geomagnetic field sufficient guidelines for radiation protection are still outstanding. For a piloted Mars mission, the whole concept of radiation protection needs to be reconsidered. Since there is an increasing interest of many nations and space agencies in establishing a lunar base and lor exploring Mars by manned missions, it is both, timely and important to develop appropriate risk estimates and radiation protection guidelines which will have an influence on the design and structure of space vehicles and habitation areas of the extraterrestrial settlements. This book is the result of a multidisciplinary effort to assess the state of art in our knowledge on the radiation situation during deep space missions and on the impact of this complex radiation environment on the space traveller. It comprises the lectures by the faculty members as well as short contributions by the students given at the NATO Advanced Study Institute "Biological Effects and Physics of Solar and Galactic Cosmic Radiation" held in Armacao de Pera, Portugal, 12-23 October, 1991.

As part of the Vision for Space Exploration (VSE), NASA is planning for humans to revisit the Moon and someday go to Mars. An important consideration in this effort is protection against the exposure to space radiation. That radiation might result in severe long-term health consequences for astronauts on such missions if they are not adequately shielded. To help with these concerns, NASA asked the NRC to further the understanding of the risks of space radiation, to evaluate radiation shielding requirements, and recommend a strategic plan for developing appropriate mitigation capabilities. This book presents an assessment of current knowledge of the radiation environment; an examination of the effects of radiation on biological systems and mission equipment; an analysis of current plans for radiation protection; and a strategy for mitigating the risks to VSE astronauts.

Life Science studies in space were initially driven by the need to explore how man could survive spaceflight conditions; the effects of being launched un der high accelerations, exposed to weightlessness and radiation for different periods of time, and returned to Earth in safety. In order to substantiate the detailed knowledge of potentially adverse effects, many model experiments were launched using organisms which ranged from bacteria, plants, inverte brates, rodents and primates through to man. Although no immediate life threatening effects were found, these experiments can be considered today as the precursors to life science research in space. Many unexplained effects on these life forms were attributed to the condition of weightlessness. Most of them were poorly recorded, poorly published, or left simply with anecdotal information. Only with the advent of Skylab, and later Spacelab, did the idea emerge, and indeed the infrastructure permit, weightlessness to be considered as an ex tended tool for research into some fundamental mechanisms or processes as sociated with the effect of gravity on organisms at all levels. The initial hy pothesis to extrapolate from hypergravity through 1 x g to near 0 x g effects could no longer be retained, since many of the experiment results were seen to contradict the models or theories in the current textbooks of biology and physiology. The past decade has been dedicated primarily to exploratory research.