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Though astronomers need naturally dark skies to see and learn about faint and distant objects in the Universe, dark skies are valuable for everyone – they have been a source of beauty and inspiration to all of Humankind for as long as people have been aware enough to raise their eyes from the ground and wonder. And light that provides visibility without waste or glare is vital for vision for everyone. The IDA, founded 30 years ago, gathers and disseminates light-pollution information and solutions. It has played a pivotal role in turning the tide in the light-pollution war. The IDA is winning over key sectors of the nonastronomical public — including government groups, sections of the lighting industry and electric utilities — arguing that good lighting for astronomers equals energy savings and more attractive surroundings for everyone else. Sometimes it is not possible to completely get rid of the problem, as this may prevent the street light from being effective so we may need to find a compromise. There is a person underneath each of these lights. In the two pictures on the left the person can see you but can you see the person? Are you really safer with more light or is it merely an illusion? Fully shielded light fixtures give you and the other person the same advantage, and minimize trespass and sky glow. Street lights district councils are responsible for District councils are responsible for street lights on unadopted highways on district council owned land, for example, car parks, parks, and amenity areas. An unadopted highway is a street which is not maintained by the local highway authority at public expense. If the street light you want to report is one of these please contact your local district council. Such a question may not strike you as entirely novel or revolutionary, as surely such questions are as old as attempts to illuminate our nights. But, the context in which this question is posed—the growing recognition of environmental and health-related problems caused or amplified by nighttime lighting—gives it new meaning. We are now seeking a transition in nighttime lighting strategies toward reducing the amount of illumination. And, it has been acknowledged that traditional approaches have been ineffective to date. Kyba, Hänel, and Hölker (2014 Kyba, C., Hänel, A., & Hölker, F. (2014). Redefining efficiency for outdoor lighting. Energy & Environmental Science, 7, 1806–1809.10.1039/C4EE00566J[Crossref], [Web of Science ®] [Google Scholar]) note that despite improvements to efficiency in lighting technologies, energy usage for outdoor lighting and artificial nighttime brightness continues to increase annually. Thus, a complete conversion to efficient lighting technologies alone (i.e. LEDs) is unlikely to reduce energy consumption or other unwanted consequences; new approaches to nighttime lighting must look beyond the narrow focus of improving efficiency. They summarize this necessary change in perspective by stating that, To place an attachment on a street light owned by us, you need to get a licence. If an outdoor lighting pole is broken, please call Xcel Energy Customer Care at 1-800-895-4999. (Except in Minnesota; continue form submission) In another study of blue light, researchers at the University of Toronto compared the melatonin levels of people exposed to bright indoor light who were wearing blue-light–blocking goggles to people exposed to regular dim light without wearing goggles. The fact that the levels of the hormone were about the same in the two groups strengthens the hypothesis that blue light is a potent suppressor of melatonin. It also suggests that shift workers and night owls could perhaps protect themselves if they wore eyewear that blocks blue light. Inexpensive sunglasses with orange-tinted lenses block blue light, but they also block other colors, so they’re not suitable for use indoors at night. Glasses that block out only blue light can cost up to $80. ¹ http://physics.fau.edu/observatory/lightpol-health.html ² http://articles.mercola.com/sites/articles/archive/2013/08/15/nutrients-better-sleep.aspx ³ https://www.sciencenews.org/article/darkness-melatonin-may-stall-breast-and-prostate-cancers ⁴ http://physics.fau.edu/observatory/lightpol-environ.html Light pollution is the adding-of/added light itself, in analogy to added sound, carbon dioxide, etc. Adverse consequences are multiple; some of them may not be known yet. Scientific definitions thus include the following: According to the International Dark-Sky Association (IDA), “Outdoor lighting with high blue light content is more likely to contribute to light pollution because it has a significantly larger geographic reach than lighting with less blue light. Blue-rich white light sources are also known to increase glare and compromise human vision. And in natural settings, blue light at night has been shown to adversely affect wildlife behavior and reproduction.” For a comprehensive understanding of light pollution, contemporary discourse must be coupled with an exploration of the origins and emergence of the concept, which in turn requires a broad understanding of the development of urban nighttime lighting. Detailed historical studies into the technological innovations and social implications of artificial nighttime lighting have been published in the past few decades (e.g. Bowers, 1998 Bowers, B. (1998). Lengthening the day: A history of lighting technology. Oxford: Oxford University Press. [Google Scholar]; Ekirch, 2005 Ekirch, R. A. (2005). At day’s close: Night in times past. New York, NY: W. W. Norton & Company Inc. [Google Scholar]; Isenstadt, Maile Petty, & Neumann, 2014 Isenstadt, S., Maile Petty, M., & Neumann, D. (Eds.). (2014). Cities of light: Two centuries of urban illumination. New York, NY: Taylor & Francis. [Google Scholar]; Nye, 1990 Nye, D. E. (1990). Electrifying America: Social meanings of a new technology, 1880–1940. Cambridge: MIT Press. [Google Scholar]; Schivelbusch, 1988 Schivelbusch, W. (1988). Disenchanted night: The industrialization of light in the nineteenth century. (A. Davis, Trans.) London: University of California Press. [Google Scholar]). And, important studies on the social, economic, and legal aspects of nighttime lighting have also been published recently (e.g. Meier, Hasenöhrl, Krause, & Pottharst, 2014 Meier, J., Hasenöhrl, U., Krause, K., & Pottharst, M. (Eds.). (2014). Urban lighting, light pollution and society. New York, NY: Taylor & Francis. [Google Scholar]). The brief discussion below cannot do full justice to the in-depth explorations of nighttime lighting that these scholars have explored, nor to the various cultural and geographical nuances of historical developments in lighting. Rather, I would like to highlight the conditions within which light pollution arose, which puts us in a better position to assess our contemporary definition and ask how the framing of light pollution responds to the core problem discussed above. In particular, Sections 3.1 and 3.2 will highlight the shift away from how to light cities and, somewhat paradoxically, toward a desire for dark or natural nights. Put otherwise, In North America the situation is comparable. There is a significant problem with light pollution ranging from the Canadian Maritime Provinces to the American Southwest.[28] The International Dark-Sky Association works to designate areas that have high quality night skies. These areas are supported by communities and organizations that are dedicated to reducing light pollution (e.g.Dark-sky preserve). The National Park Service Natural Sounds and Night Skies Division has measured night sky quality in national park units across the U.S. Sky quality in the U.S. ranges from pristine (Capitol Reef National Park and Big Bend National Park) to severely degraded (Santa Monica Mountains National Recreation Area and Biscayne National Park).[29] The National Park Service Night Sky Program monitoring database is available online (2015).[30] While light of any kind can suppress the secretion of melatonin, blue light at night does so more powerfully. Harvard researchers and their colleagues conducted an experiment comparing the effects of 6.5 hours of exposure to blue light to exposure to green light of comparable brightness. The blue light suppressed melatonin for about twice as long as the green light and shifted circadian rhythms by twice as much (3 hours vs. 1.5 hours). Such a question may not strike you as entirely novel or revolutionary, as surely such questions are as old as attempts to illuminate our nights. But, the context in which this question is posed—the growing recognition of environmental and health-related problems caused or amplified by nighttime lighting—gives it new meaning. We are now seeking a transition in nighttime lighting strategies toward reducing the amount of illumination. And, it has been acknowledged that traditional approaches have been ineffective to date. Kyba, Hänel, and Hölker (2014 Kyba, C., Hänel, A., & Hölker, F. (2014). Redefining efficiency for outdoor lighting. Energy & Environmental Science, 7, 1806–1809.10.1039/C4EE00566J[Crossref], [Web of Science ®] [Google Scholar]) note that despite improvements to efficiency in lighting technologies, energy usage for outdoor lighting and artificial nighttime brightness continues to increase annually. Thus, a complete conversion to efficient lighting technologies alone (i.e. LEDs) is unlikely to reduce energy consumption or other unwanted consequences; new approaches to nighttime lighting must look beyond the narrow focus of improving efficiency. They summarize this necessary change in perspective by stating that, erogan power up premium Testogen TestX Core Celuraid Muscle Maxman Steroïden Penigen 500 Eron Plus el macho

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