written to the FCC<\/a>, said: \u201cWhile ideas like mirrors on satellites beaming \u2018sunlight on demand\u2019 to Earth or mega-constellations of up to 1m satellites for AI datacentres may sound like science fiction, these proposals are very real.\u201d<\/p>\nHe added: \u201cScientific studies have already shown that the existing number of satellites in orbit has increased diffuse night sky brightness, or sky glow, by roughly 10%.\u201d<\/p>\n
A blend of exposures showing all the satellites in a crowded sky from Alberta, Canada, in June 2022. Photograph: Alan Dyer\/Getty Images\/Stocktrek Images<\/p>\n
Satellites affected the night sky in two main ways, Dr Miroslav Kocifaj, of the Slovak Academy of Sciences, in Bratislava, said. Individual satellites could leave streaks in telescope images, while sunlight reflected by satellites and debris brightened the sky.<\/p>\n
His modelling suggests these objects already add between 3 and 8 microcandela per square metre to night sky brightness. By 2035, he predicts this could rise to between 5 and 19 microcandela, approaching the threshold astronomers have set for preserving naturally dark skies.<\/p>\n
While this additional brightness remains far below that of moonlight, \u201cwhat I can say with confidence is that the phenomenon is real, that it is global and cannot be escaped by moving to a more remote location, and that it will increase substantially over the coming decade if current trends in satellite launches and debris generation continue\u201d, Kocifaj said.<\/p>\n
Prof Tami Martino, of the University of Guelph, who is president of the Canadian Society of Chronobiology, said when it came to impacts on life on Earth, \u201cthe real question is not brightness compared to moonlight, but whether biological systems can detect the change\u201d.<\/p>\n
Waterloo Bridge in London. Prof Martino says circadian systems are \u2018sensitive to light levels far below what humans typically perceive as bright\u2019. Photograph: DA Cameron\/Alamy<\/p>\n
\u201cCircadian systems are sensitive to light levels far below what humans typically perceive as bright,\u201d Martino said. \u201cIf the night sky becomes permanently brighter, the consequences could ripple through ecosystems in ways we do not yet fully understand.\u201d<\/p>\n
A separate letter from the presidents of the World Sleep Society, European Sleep Research Society, Sleep Health Foundation, Australian Sleep Association and Australasian Chronobiology Society said \u201ccircadian disruption is not mere inconvenience; it is a physiological mechanism driving major adverse health consequences\u201d.<\/p>\n
\u201cWe do not argue against space innovation,\u201d the letter added, saying that altering the night sky should be treated with the same seriousness as other planetary-scale environmental changes, such as climate change and ocean acidification. \u201cThe alternation of light and dark is not a trivial background condition. It is one of the oldest organising principles of life on Earth.\u201d<\/p>\n
Hartley said that as satellite numbers grew, fast-moving artificial objects could become a dominant feature of the night sky. \u201cThere could be times and places where satellites outnumber the visible stars,\u201d he said. Many birds and some insects navigated using the stars, and the human experience of the night sky could also be profoundly altered.<\/p>\n
Reflect Orbital\u2019s plans would also introduce a new form of light pollution with largely unstudied consequences, including potential public-safety risks, Hartley said. \u201cAs these beams move across the landscape, there is the possibility of intense glare or blinding flashes, particularly if systems malfunction or drift off target. These are exactly the kinds of risks that need to be carefully studied, which is why DarkSky is calling for a full environmental review before proposals like this move forward.\u201d<\/p>\n
Reflect Orbital declined to comment, while SpaceX did not respond to a request for comment.<\/p>\n","protected":false},"excerpt":{"rendered":"Proposals to deploy reflective mirrors and up to 1m more satellites in low Earth orbit could have far-reaching…\n","protected":false},"author":2,"featured_media":514243,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[23],"tags":[90,416,56,54,55],"class_list":{"0":"post-514242","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-space","8":"tag-science","9":"tag-space","10":"tag-uk","11":"tag-united-kingdom","12":"tag-unitedkingdom"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/514242","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/comments?post=514242"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/514242\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media\/514243"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media?parent=514242"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/categories?post=514242"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/tags?post=514242"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}