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StillnessNight environment fact

Light pollution, the glow from artificial light we do not need at night, now hides the Milky Way from about a third of humanity. It also blurs the darkness that birds, insects, plants and people rely on to rest, find their way and tell night from day.

NASA / DarkSky International

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The story behind the card

The figure comes from a world atlas of night-sky brightness published in 2016, which found the Milky Way hidden from about 60 per cent of Europeans and nearly 80 per cent of North Americans. Night-migrating birds partly steer by the stars and are drawn towards lit towers and buildings, where many circle until exhausted or fly into glass; US estimates for deaths at towers alone run from four or five million birds a year to ten times that. Insects swarm and die around lamps, and artificial light can shift when some plants come into bud. Programmes such as Toronto's Fatal Light Awareness Program ask building owners to switch off lights during migration.

Türkçe oku
Işık kirliliği, geceleri gereksiz yere yanan yapay ışığın gökyüzüne taşmasıdır. Bugün insanlığın yaklaşık üçte biri bu yüzden Samanyolu'nu göremiyor; kuşlar, böcekler, bitkiler ve insanlar da dinlenmek, yön bulmak ve geceyi gündüzden ayırmak için ihtiyaç duydukları karanlığı yitiriyor.

Bu rakam, 2016'da yayımlanan bir gece gökyüzü parlaklığı atlasından geliyor. Atlasa göre Avrupalıların yaklaşık yüzde 60'ı, Kuzey Amerikalıların ise yüzde 80'e yakını Samanyolu'nu artık göremiyor. Gece göç eden kuşlar yönlerini kısmen yıldızlara bakarak bulur; ışıklı kulelere ve binalara çekilir, bitkin düşene kadar çevrelerinde döner ya da camlara çarparlar. ABD'de yalnızca kulelere çarparak ölen kuşların sayısı, yılda dört beş milyondan bunun on katına kadar uzanan tahminlerle hesaplanıyor. Böcekler lambaların çevresinde toplanıp ölüyor, yapay ışık bazı bitkilerin tomurcuklanma zamanını bile kaydırabiliyor. Toronto'daki Fatal Light Awareness Program (Ölümcül Işık Farkındalık Programı) gibi girişimler, bina sahiplerinden göç dönemlerinde ışıklarını söndürmelerini istiyor.

Sources and further reading

Background reading: Light pollution
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