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Arctic Circle
The Arctic Circle is one of the five major circles of latitude that mark maps of the Earth. This is the parallel of latitude that (in 2000) runs 66.56083 degrees north of the Equator. Everything north of this circle is known as the Arctic, and the zone just to the south of this circle is the Northern Temperate Zone.
The Arctic Circle marks the southern extremity of the polar day (24 hour sunlit day) of the summer solstice in June and the polar night (24 hour sunless night) of the winter solstice in December. Within the Arctic Circle, the Sun is above the horizon for 24 continuous hours at least once per year, in conjunction with the Arctic's Summer Solstice. Likewise, in conjunction with the Arctic’s Winter Solstice, the Arctic sun will be below the horizon for at least 24 continuous hours.
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Earth & Climate News
November 6, 2025
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Nov. 4, 2025 — Beneath the ocean’s surface, bacteria have evolved specialized enzymes that can digest PET plastic, the material used in bottles and clothes. Researchers at KAUST discovered that a unique molecular signature distinguishes enzymes capable of ...
Nov. 3, 2025 — Bamboo tissue paper, often marketed as an eco-friendly alternative, may not be as green as consumers think. Researchers at NC State University found that while bamboo fibers themselves are not more polluting than wood, China’s coal-dependent ...
Nov. 3, 2025 — UIC researchers predict that the Sahara Desert could see up to 75% more rain by the end of this century due to rising global temperatures. Using 40 climate models, the team found widespread precipitation increases across Africa, though some regions ...
Nov. 2, 2025 — UC Davis scientists uncovered Aptostichus ramirezae, a new trapdoor spider species living under California’s dunes. Genetic analysis revealed it was distinct from its close relative, Aptostichus simus. The species was named after pioneering ...
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Nov. 2, 2025 — Researchers discovered that soil microbes in Kansas carry drought “memories” that affect how plants grow and survive. Native plants showed stronger responses to these microbial legacies than crops like corn, hinting at co-evolution over time. ...
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Oct. 31, 2025 — The Taurid meteor shower, born from Comet Encke, delights skywatchers but may conceal hidden risks. Research led by Mark Boslough examines potential Taurid swarms that could increase impact danger in ...
Oct. 31, 2025 — Earth’s magnetosphere, once thought to have a simple electric polarity pattern, has revealed a surprising twist. New satellite data and advanced simulations show that the morning side of the ...
Oct. 30, 2025 — Researchers in Japan have revealed how some gourds draw pollutants into their fruits. The secret lies in a protein that carries contaminants through the plant sap. By manipulating this protein’s ...
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Oct. 30, 2025 — A new species of mountain lizard, Diploderma bifluviale, has been discovered in the upper Dadu River Valley of China. Its distinct traits and isolated habitat highlight the hidden biodiversity of the ...
Oct. 29, 2025 — Global scientists warn that humanity is on the verge of crossing irreversible climate thresholds, with coral reefs already at their tipping point and polar ice sheets possibly beyond recovery. The ...
Oct. 29, 2025 — Researchers at QUT uncovered how corals reattach to reefs through a three-phase process involving tissue transformation, anchoring, and skeleton formation. Differences among species reveal why some ...