In the history of science the opening up of a new observational or experimental window is always followed by an increase in knowledge of the subject concerned. This is also the case with the subject of this book, ultraviolet radiation (hereafter UV). In principle, the ultraviolet range might be just one more of these windows, of no particular importance. However, the energy per UV photon provides the main peculiarity, its magnitude being great enough to produce important ch- ical reactions in the atmospheres of planets and satellites, thereby a?ecting the transmission of this radiation to the ground. The Sun is the main natural source of UV radiation in the Solar System and our planet is the body where its in?uences can be best tested and the only one where its relation with life can be studied. However, the terrestrial atmosphere blocksmostofthephotonsinthiselectromagneticrangeandastronomershavehad to develop various techniques (balloons, planes and rockets) to cross this barrier and access the information. These tools have been used in parallel to investigate the physical properties of the terrestrial atmosphere and the interaction of its constituents with light. This book will addresses most of these topics.

Numerous studies report that ultraviolet (UV) radiation is harmful to living organisms and detrimental to human health. Growing concerns regarding the increased levels of UV-B radiation that reach the earth's surface have led to the development of ground- and space-based measurement programs. Further study is needed on the measurement, modeling, and effects of UV radiation. The chapters of this book describe the research conducted across the globe over the past three decades in the areas of: (1) current and predicted levels of UV radiation and its associated impact on ecosystems and human health, as well as economic and social implications; (2) new developments in UV instrumentation, advances in calibration (ground- and satellite-based), measurement methods, modeling efforts, and their applications; and (3) the effects of global climate change on UV radiation. Dr. Wei Gao is a Senior Research Scientist and the Director of the USDA UV-B Monitoring and Research Program, Natural Resource Ecology Laboratory, Colorado State University. Dr. Gao is a SPIE fellow and serves as the Editor-in-Chief for the Journal of Applied Remote Sensing. Dr. Daniel L. Schmoldt is the National Program Leader for instrumentation and sensors at the National Institute of Food and Agriculture (NIFA) of the U.S. Department of Agriculture. Dr. Schmoldt served as joint Editor-in-Chief of the journal, Computers & Electronics in Agriculture, from 1997 to 2004. Dr. James R. Slusser retired in 2007 from the USDA UV-B Monitoring and Research Program at Colorado State University. He was active in the Society of Photo-Optical Instrumentation Engineers, the American Geophysical Union, and the American Meteorological Society. Dr. Slusser is currently pursuing his interests in solar energy and atmospheric transmission.

Ultraviolet Astronomy and the Quest for the Origin of Life addresses the use of astronomical observations in the ultraviolet range to better understand the generation of complex, life-precursor molecules. The origin of RNA is still under debate but seems to be related to the generation of pools of complex organic molecules submitted to heavy cycles of solution in water and drying. This book investigates whether these cycles require a planetary surface or may occur in space by examining both the theoretical and observational aspects of the role of UV radiation in the origin of life. This book offers the latest advances in these studies for astronomers, astrobiologists and planetary scientists. - Addresses both the theoretical and observational aspects of the role of Ultraviolet (UV) radiation in the origin of life - Builds on the requirements to produce prebiotic molecules in space and the implications for the origin of RNA - Investigates the use of ultraviolet observations related to planetary system formation, the evolution of young planetary disks, and the interaction of stars with planetary atmospheres

" ... Concise explanations and descriptions - easily read and readily understood - of what we know of the chain of events and processes that connect the Sun to the Earth, with special emphasis on space weather and Sun-Climate."--Dear Reader.

The field of planetary biology and chemical evolution draws together experts in astronomy, paleobiology, biochemistry, and space science who work together to understand the evolution of living systems. This field has made exciting discoveries that shed light on how organic compounds came together to form self-replicating molecules-the origin of life. This volume updates that progress and offers recommendations on research programs-including an ambitious effort centered on Mars-to advance the field over the next 10 to 15 years. The book presents a wide range of data and research results on these and other issues: The biogenic elements and their interaction in the interstellar clouds and in solar nebulae. Early planetary environments and the conditions that lead to the origin of life. The evolution of cellular and multicellular life. The search for life outside the solar system. This volume will become required reading for anyone involved in the search for life's beginnings-including exobiologists, geoscientists, planetary scientists, and U.S. space and science policymakers.

In the early 20th century, tanned skin was associated with good health. However, people began to protect themselves against potential overexposure to avoid sunburns. Around 1945, the first sunscreen products became available. In the years to follow, a vast number of different sunscreen filters and frameworks regulating filter substances and preparations, and methods characterizing sunscreen products were developed. The perception regarding the tasks of sunscreen products changed several times – initially it was promoted as a lifestyle product, then as a skin cancer preventive means, and more recently also for anti-aging. Different purposes and the widespread use of these products have led to myriad studies and a wealth of information. In this volume, the editors present a current collection of information analyzing and discussing issues related to sunscreen products and their use. These include challenges regarding the ideal sunscreen product including filter selection and formulation issues, measurement methods, performance characterization, safety, and regulatory issues. Further papers address topics related to the use of sunscreen products in everyday life, in vulnerable cohorts and outdoor workers. Controversial topics such as environmental effects of sunscreen products and the risks and benefits of UV radiation in the context of skin cancer, vitamin D and cardiovascular and metabolic health are also covered.

Ultraviolet-B (UV-B) is electromagnetic radiation coming from the sun, with a medium wavelength which is mostly absorbed by the ozone layer. The biological effects of UV-B are greater than simple heating effects, and many practical applications of UV-B radiation derive from its interactions with organic molecules. It is considered particularly harmful to the environment and living things, but what have scientific studies actually shown? UV-B Radiation: From Environmental Stressor to Regulator of Plant Growth presents a comprehensive overview of the origins, current state, and future horizons of scientific research on ultraviolet-B radiation and its perception in plants. Chapters explore all facets of UV-B research, including the basics of how UV-B's shorter wavelength radiation from the sun reaches the Earth's surface, along with its impact on the environment's biotic components and on human biological systems. Chapters also address the dramatic shift in UV-B research in recent years, reflecting emerging technologies, showing how historic research which focused exclusively on the harmful environmental effects of UV-B radiation has now given way to studies on potential benefits to humans. Topics include: UV-B and its climatology UV-B and terrestrial ecosystems Plant responses to UV-B stress UB- B avoidance mechanisms UV-B and production of secondary metabolites Discovery of UVR8 Timely and important, UV-B Radiation: From Environmental Stressor to Regulator of Plant Growth is an invaluable resource for environmentalists, researchers and students who are into the state-of-the-art research being done on exposure to UV-B radiation.