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In addition to skyglow, light trespass can impact observations when artificial light directly enters the tube of the telescope and is reflected from non-optical surfaces until it eventually reaches the eyepiece. This direct form of light pollution causes a glow across the field of view which reduces contrast. Light trespass also makes it hard for a visual observer to become sufficiently dark adapted. The usual measures to reduce this glare, if reducing the light directly is not an option, include flocking the telescope tube and accessories to reduce reflection, and putting a light shield (also usable as a dew shield) on the telescope to reduce light entering from angles other than those near the target. Under these conditions, some astronomers prefer to observe under a black cloth to ensure maximum dark adaptation. In one Italian regional lighting code this effect of stray light is defined as “optical pollution”[citation needed], due to the fact that there is a direct path from the light source to the “optic” – the observer’s eye or telescope. Outages are usually repaired within five working days. If the fault is regarding the electricity supply to the light we inform the local electricity company who usually attend within eight working days of receiving report. Use this form to report a problem with a street light or a lit bollard. I just dropped my camera and now the red light isn’t going away please help me To precisely measure how bright the sky gets, night time satellite imagery of the earth is used as raw input for the number and intensity of light sources. These are put into a physical model[26] of scattering due to air molecules and aerosoles to calculate cumulative sky brightness. Maps that show the enhanced sky brightness have been prepared for the entire world.[27] A Safe, Low-Cost Alternative to Kerosene lighting The big bang model assumes that the universe is many billions of years old. While this timescale is sufficient for light to travel from distant galaxies to earth, it does not provide enough time for light to travel from one side of the visible universe to the other. At the time the light was emitted, supposedly 300,000 years after the big bang, space already had a uniform temperature over a range at least ten times larger than the distance that light could have travelled (called the ‘horizon’)11 So, how can these regions look the same, i.e. have the same temperature? How can one side of the visible universe ‘know’ about the other side if there has not been enough time for the information to be exchanged? This is called the ‘horizon problem’.12 Secular astronomers have proposed many possible solutions to it, but no satisfactory one has emerged to date (see Attempts to overcome the big bang’s ‘light-travel–time problem’). Please use this form to report a lighting issue. Your Check Engine Light may be indicating a simple problem that’s easy to fix – such as a loose gas cap. Or, it could be a warning of a more serious problem that could damage your engine components. Finding out why your light is on now can save you money and trouble down the road. You’re driving along in your car or truck and suddenly a yellow light illuminates on your dash telling you to check or service your engine. If you’re like most car owners, you have little idea about what that light is trying to tell you or how you should react. We’re converting many of our street lights to energy-efficient Light Emitting Diode (LED) technology. Read more about our LED street lighting project. The below discussion is organized under two broad questions, with the aim of elucidating the moral limitations and practical ambiguities existing within the concept of light pollution, when considered as a framework for moral and political decision-making. These two sections should not be seen as mutually exclusive, but as actively informing one another. A study presented at the American Geophysical Union meeting in San Francisco found that light pollution destroys nitrate radicals thus preventing the normal night time reduction of atmospheric smog produced by fumes emitted from cars and factories.[82][83] The study was presented by Harald Stark from the National Oceanic and Atmospheric Administration. Disadvantages of low pressure sodium lighting are that fixtures must usually be larger than competing fixtures, and that color cannot be distinguished, due to its emitting principally a single wavelength of light (see security lighting). Due to the substantial size of the lamp, particularly in higher wattages such as 135 W and 180 W, control of light emissions from low pressure sodium luminaires is more difficult. For applications requiring more precise direction of light (such as narrow roadways) the native lamp efficacy advantage of this lamp type is decreased and may be entirely lost compared to high pressure sodium lamps. Allegations that this also leads to higher amounts of light pollution from luminaires running these lamps arise principally because of older luminaires with poor shielding, still widely in use in the UK and in some other locations. Modern low-pressure sodium fixtures with better optics and full shielding, and the decreased skyglow impacts of yellow light preserve the luminous efficacy advantage of low-pressure sodium and result in most cases is less energy consumption and less visible light pollution. Unfortunately, due to continued lack of accurate information,[92] many lighting professionals continue to disparage low-pressure sodium, contributing to its decreased acceptance and specification in lighting standards and therefore its use. Another disadvantage of low-pressure sodium lamps is that some people find the characteristic yellow light very displeasing aesthetically.[citation needed] Please note that street lights are fixed as soon as possible, depending upon when crews are in the area and workload. Light pollution, also known as photopollution, is the presence of anthropogenic light in the night environment. It is exacerbated by excessive, misdirected or obtrusive uses of light, but even carefully used light fundamentally alters natural conditions. As a major side-effect of urbanization, it is blamed for compromising health, disrupting ecosystems and spoiling aesthetic environments. When artificial light affects organisms and ecosystems it is called ecological light pollution. While light at night can be beneficial, neutral, or damaging for individual species, its presence invariably disturbs ecosystems. For example, some species of spiders avoid lit areas, while other species are happy to build their spider web directly on a lamp post. Since lamp posts attract many flying insects, the spiders that don’t mind light, gain an advantage over the spiders that avoid it. This is a simple example of the way in which species frequencies and food webs can be disturbed by the introduction of light at night. Clarifications to the ambiguities discussed above will likely change alongside differences in geographies, cultures, and belief systems. The recent edited volume Cities of Light (Isenstadt et al., 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]) provides a first overview of historic developments in nighttime illumination with respect to individual cities, a format that could be expanded to contemporary environmental debates. But regardless, if light pollution will be the frame through which regulations are established, anticipating value-level conflicts and ambiguities is important. We must clarify—or at the least debate—the normative foundations of light pollution before the framework becomes normalized and fades into the background of presuppositions informing nighttime lighting strategies. This light is switched off for energy saving. An English journal has become alarmed at the relation of electricity to songbirds, which it maintains is closer than that of cats and fodder crops. How many of us, it asks, foresee that electricity may extirpate the songbird?…With the exception of the finches, all the English songbirds may be said to be insectivorous, and their diet consists chiefly of vast numbers of very small insects which they collect from the grass and herbs before the dew is dry. As the electric light is finding its way for street illumination into the country parts of England, these poor winged atoms are slain by thousands at each light every warm summer evening….The fear is expressed, that when England is lighted from one end to the other with electricity the song birds will die out from the failure of their food supply.[77] Tonus Fortis eracto Masculin Active TestX Core BeMass TestX Core eracto Masculin Active xtrasize erogran