Editing Light pollution (section)

==Definitions==

Light [[pollution]] is the presence of [[Anthropogenic hazard|anthropogenic]] artificial light in otherwise dark conditions.<ref>{{Cite journal
| last1 = Verheijen | first1 = F. J.
| title = Photopollution: Artificial light optic spatial control systems fail to cope with. Incidents, causation, remedies
| journal = Experimental Biology
| volume = 44
| issue = 1
| pages = 1–18
| year = 1985
| pmid = 3896840
}}</ref><ref>{{cite journal|doi=10.1046/j.1365-8711.2000.03562.x|date=2000|last1=Cinzano|pages=641–657|volume=318|journal=[[Monthly Notices of the Royal Astronomical Society]]|url=http://www.lightpollution.it/cinzano/download/mnras_paper.pdf|first1=P.|last2=Falchi|first2=F.|last3=Elvidge|first3=C. D.|last4=Baugh|first4=K. E.|title=The artificial night sky brightness mapped from DMSP Operational Linescan System measurements|issue=3|doi-access=free |arxiv=astro-ph/0003412|bibcode=2000MNRAS.318..641C|s2cid=15679234|access-date=2010-03-31|archive-date=2021-03-11|archive-url=https://web.archive.org/web/20210311010238/http://www.lightpollution.it/cinzano/download/mnras_paper.pdf|url-status=live}}</ref><ref>[http://amper.ped.muni.cz/light/lp_what_is.pdf Hollan, J: What is light pollution, and how do we quantify it?] {{Webarchive|url=https://web.archive.org/web/20110718180717/http://amper.ped.muni.cz/light/lp_what_is.pdf |date=2011-07-18 }}. Darksky2008 conference paper, Vienna, August 2008. Updated April 2009.</ref><ref>Marín, C. and Orlando, G. (eds.) (June 2009) [http://www.starlight2007.net/pdf/FinalReportFuerteventuraSL.pdf Starlight Reserves and World Heritage] {{Webarchive|url=https://web.archive.org/web/20200927091205/https://www.starlight2007.net/pdf/FinalReportFuerteventuraSL.pdf |date=2020-09-27 }}. Starlight Initiative, IAC and the UNESCO World Heritage Centre. Fuerteventura, Spain.</ref>

The term is most commonly used in relation to in the outdoor environment and surrounding, but is also used to refer to artificial light indoors. Adverse consequences are multiple; some of them may not be known yet. Light pollution competes with starlight in the [[night sky]] for urban residents, interferes with [[astronomy|astronomical]] [[observatory|observatories]],<ref>{{cite web |url=http://www.astro.caltech.edu/palomar/community/lightpollution.html |title=Light Pollution and Palomar Observatory |publisher=[[Caltech]] Astronomy |location=[[Palomar Observatory]] |access-date=2014-12-07 |archive-date=2020-07-04 |archive-url=https://web.archive.org/web/20200704034009/https://www.astro.caltech.edu/palomar/community/lightpollution.html |url-status=live }}</ref> and, like any other form of [[pollution]], disrupts [[ecosystem]]s and has adverse health effects.
<ref>{{cite web|url=https://www.latimes.com/science/sciencenow/la-sci-sn-earth-artificial-light-night-darkness-20171122-story.html|title=Artificial lights are eating away at dark nights—and that's not a good thing|first=Amina|last=Khan|website=[[Los Angeles Times]]|date=22 November 2017|access-date=20 December 2018|archive-date=11 March 2021|archive-url=https://web.archive.org/web/20210311005518/https://www.latimes.com/science/sciencenow/la-sci-sn-earth-artificial-light-night-darkness-20171122-story.html|url-status=live}}</ref><ref>{{cite news|url=https://www.reuters.com/article/us-science-light-idUSKBN1DM2OK|title=The future looks bright: light pollution rises on a global scale|date=22 November 2017|access-date=20 December 2018|via=www.reuters.com|work=Reuters|archive-date=11 March 2021|archive-url=https://web.archive.org/web/20210311005518/https://www.reuters.com/article/us-science-light-idUSKBN1DM2OK|url-status=live}}</ref>
<ref>{{cite journal |last1=Lamphar |first1=Héctor |last2=Kocifaj |first2=Miroslav |last3=Limón-Romero |first3=Jorge |last4=Paredes-Tavares |first4=Jorge |last5=Chakameh |first5=Safei Diba |last6=Mego |first6=Michal |last7=Prado |first7=Natalia Jorgelina |last8=Baez-López |first8=Yolanda Angélica |last9=Diez |first9=Emiliano Raúl |title=Light pollution as a factor in breast and prostate cancer |journal=Science of the Total Environment |date=1 February 2022 |volume=806 |issue=Pt 4 |pages=150918 |doi=10.1016/j.scitotenv.2021.150918|pmid=34653461 |bibcode=2022ScTEn.80650918L |s2cid=239003677 }}</ref>
Light pollution is a side-effect of industrial civilization. Its sources include building exterior and interior lighting, advertising, outdoor area lighting (such as car parks), offices, factories, streetlights, and illuminated sporting venues. It is most severe in highly industrialized, densely populated areas of North America, Europe, and Asia and in major cities in the Middle East and North Africa like [[Tehran]] and [[Cairo]], but even relatively small amounts of light can be noticed and create problems. Awareness of the harmful effects of light pollution began in the second half of the 19th century,<ref>{{cite book|last1=Guillemain|first1=Amédée|title=Le Ciel, notions d'astronomie à l'usage des gens du monde et de la jeunesse|date=1864|publisher=Librairie de L. Hachette et Cie|location=Paris|pages=101, 383|url=https://gallica.bnf.fr/ark:/12148/bpt6k62098808/f13.item.r|access-date=2021-02-07|archive-date=2021-03-11|archive-url=https://web.archive.org/web/20210311005601/https://gallica.bnf.fr/ark:/12148/bpt6k62098808/f13.item.r|url-status=live}}</ref> but efforts to address its effects did not begin until the 1950s.<ref>{{cite journal|last1=Portree|first1=David. S. F.|title=Flagstaff's Battle for Dark Skies|journal=The Griffith Observer|date=2002|issue=October, 2002}}</ref> In the 1980s a global [[dark-sky movement]] emerged with the founding of the [[International Dark-Sky Association]] (IDA). There are now such educational and advocacy organizations in many countries worldwide.

About 83% of people, including 99% of Europeans and Americans, live under light-polluted skies that are more than 10% brighter than natural darkness.  80% of North Americans cannot see the [[Milky Way]] galaxy.<ref>{{Cite web |last=Yong |first=Ed |date=2022-06-13 |title=How Animals Perceive the World |url=https://www.theatlantic.com/magazine/archive/2022/07/light-noise-pollution-animal-sensory-impact/638446/ |access-date=2022-06-14 |website=The Atlantic |language=en |archive-date=2023-06-03 |archive-url=https://web.archive.org/web/20230603170150/https://www.theatlantic.com/magazine/archive/2022/07/light-noise-pollution-animal-sensory-impact/638446/ |url-status=live }}</ref>