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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
October 13, 2026
Oct. 12, 2026 Europe's Sentinel-3C satellite has returned breathtaking images of Earth just two weeks after launch, revealing the snowy Alps, frozen Arctic islands, and brilliant turquoise Caribbean waters. Its ...
Oct. 12, 2026 Scientists may have solved a 2.3-billion-year-old mystery about how Earth maintained enough oxygen to support life. Ancient rocks reveal that phosphorus recycling in the oceans created a ...
Oct. 12, 2026 Australia's normally dry, rust-colored outback has erupted into a spectacular carpet of wildflowers after unusually heavy rains, potentially producing its most impressive bloom in nearly 20 years. NASA satellite images capture the stunning ...
Oct. 8, 2026 A brilliant yellow coral discovered off Costa Rica proved so unusual that scientists had to create an entirely new family to classify it. The meter-tall colonies rise from seafloors covered in brittle stars, inspiring the Tolkien-inspired name ...
Oct. 7, 2026 Earth’s center of mass is constantly on the move, shifting by a few millimeters as enormous amounts of water, ice, and even air migrate around the planet with the seasons. NASA scientists have developed a more precise way to track these tiny ...
Oct. 4, 2026 A meteor crater buried beneath Oklahoma has turned out to be nearly 100 million years younger than scientists thought. Zircon crystals show the Ames impact occurred about 370 million years ago, meaning it was not part of the mysterious Ordovician ...
Oct. 4, 2026 A 30-year forestry experiment in Australia found that heavily thinned mountain ash forests grew unusually large trees while recovering enough carbon to match or exceed untouched areas. The results suggest carefully managed thinning could support ...
Oct. 4, 2026 A new light-activated material can efficiently produce hydrogen from water without requiring an additional expensive metal catalyst. Researchers say its unusual sulfur-based chemistry could point toward cheaper and more practical ways to turn ...
Oct. 1, 2026 A new protective fabric boosted strawberry yields by as much as 3.56 times while blocking insects and still allowing sunlight, rain, and airflow to reach the plants. Originally inspired by research on military clothing, Plant Armor could also help ...
Sep. 30, 2026 Marine heatwaves may be only the most intense part of much longer warming events, with elevated temperatures sometimes lingering for months. Researchers found that conventional measurements underestimate total heat exposure by more than 150% on ...
Sep. 27, 2026 Scientists have streamlined a method for measuring DNA-bound phosphorus in soil, making it cheaper and easier while preserving its accuracy. The technique could reveal how soil microbes help recycle phosphorus and ultimately support more sustainable ...
Sep. 27, 2026 Scientists studying ancient Australian rocks uncovered more than 12,000 fossils from some of the oldest known eukaryotes on Earth. These early complex cells lived in settings ranging from coastal ...
Latest Headlines
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Oct. 11, 2026 An astronaut aboard the International Space Station photographed a remarkable formation in Madagascar that looks surprisingly similar to the Moon’s bright highlands. Made of anorthosite, a rock ...
Oct. 6, 2026 New research suggests animals could have evolved as early as 800 to 700 million years ago, roughly 200 million years earlier than some previous estimates. If so, the first animals may have lived ...
Oct. 2, 2026 Researchers say stress on Southern California’s San Andreas and San Jacinto faults has reached some of the highest levels seen in a 1,000-year ...
Sep. 30, 2026 Mount Vesuvius’ famous 79 CE eruption has given scientists a remarkably precise benchmark for dating events deep in Earth’s past. The improved ...
Sep. 29, 2026 Scientists may have solved why the length of Earth’s day changes by a few milliseconds over decades. Subtle shifts in the inner core appear to tug ...
Sep. 26, 2026 Scientists have found that a famous 2-billion-year-old chemical signature, once thought to record a massive global change in Earth’s carbon cycle, may instead have been produced by local magma, ...
Sep. 25, 2026 Scientists have captured a subduction zone off Vancouver Island in the process of tearing itself apart, revealing that these massive tectonic systems may die piece by piece rather than all at once. ...
Sep. 24, 2026 Scientists discovered two tiny new snail species in Montenegro, showing that even Europe still holds animals unknown to science. One lives in the threatened Komarnica Canyon, where a proposed ...
Sep. 23, 2026 The Cascadia subduction zone and northern San Andreas fault may sometimes rupture in rapid succession, according to evidence preserved in 3,100 years ...
Sep. 23, 2026 Some tropical trees have evolved a clever way to survive drought by taking in carbon dioxide at night, allowing them to keep their pores closed during the hot daytime and conserve water. By comparing ...