Reference Terms
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Ionosphere
The ionosphere is the part of the atmosphere that is ionized by solar radiation. It plays an important part in atmospheric electricity and forms the inner edge of the magnetosphere. It has practical importance because, among other functions, it influences radio propagation to distant places on the Earth. The lowest part of the Earth's atmosphere is called the troposphere and it extends from the surface up to about 10 km (6 miles). The atmosphere above 10 km is called the stratosphere, followed by the mesosphere. It is in the stratosphere that incoming solar radiation creates the ozone layer. At heights of above 80 km (50 miles), in the thermosphere, the atmosphere is so thin that free electrons can exist for short periods of time before they are captured by a nearby positive ion. The number of these free electrons is sufficient to affect radio propagation. This portion of the atmosphere is ionized and contains a plasma which is referred to as the ionosphere. In a plasma, the negative free electrons and the positive ions are attracted to each other by the electromagnetic force, but they are too energetic to stay fixed together in an electrically neutral molecule. The ionosphere has irregular patches of ionization.
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Earth & Climate News
December 26, 2025
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Dec. 22, 2025 Washing machines release massive amounts of microplastics into the environment, mostly from worn clothing fibers. Researchers at the University of Bonn have developed a new, fish-inspired filter that removes over 99% of these particles without ...
Dec. 21, 2025 Scientists have uncovered a missing feedback in Earth’s carbon cycle that could cause global warming to overshoot into an ice age. As the planet warms, nutrient-rich runoff fuels plankton blooms that bury huge amounts of carbon in the ocean. In ...
Dec. 21, 2025 Old military air samples turned out to be a treasure trove of biological DNA, allowing scientists to track moss spores over 35 years. The results show mosses now release spores up to a month earlier than in the 1990s. Even more surprising, the ...
Dec. 19, 2025 New research reveals when glaciers around the world will vanish and why every fraction of a degree of warming could decide their ...
Dec. 18, 2025 Much of the western U.S. is overdue for wildfire, with decades of suppression allowing fuel to build up across millions of hectares. Researchers estimate that 74% of the region is in a fire deficit, meaning far more land needs to burn to restore ...
Dec. 15, 2025 Around 1,000 years ago, a major climate shift reshaped rainfall across the South Pacific, making western islands like Samoa and Tonga drier while eastern islands such as Tahiti became increasingly ...
Dec. 13, 2025 Researchers analyzing ancient fossils from caves across Western Australia have uncovered a completely new species of bettong along with two new woylie subspecies—remarkable finds made bittersweet by signs that some may already be ...
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Latest Headlines
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Dec. 26, 2025 When Earth was a molten inferno, water may have been locked safely underground rather than lost to space. Researchers discovered that bridgmanite ...
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Dec. 19, 2025 Cosmic “touchdown airbursts” — explosions of comets or asteroids above Earth’s surface — may be far more common and destructive than previously thought, according to new research. Unlike ...
Dec. 16, 2025 A rare, ultra-long earthquake in Myanmar revealed that mature faults can deliver their full force directly to the surface. The discovery could mean stronger shaking near faults like California’s ...
Dec. 12, 2025 A sudden, unexplained mass die-off is decimating sea urchins around the world, including catastrophic losses in the Canary Islands. Key reef-grazing species are reaching historic lows, and their ...
Dec. 12, 2025 Fossils from Qatar have revealed a small, newly identified sea cow species that lived in the Arabian Gulf more than 20 million years ago. The site contains the densest known collection of fossil sea ...
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Dec. 11, 2025 Scientists tracking young Arizona Bald Eagles found that many migrate north during summer and fall, bucking the traditional southbound pattern of most birds. Their routes rely heavily on historic ...
Dec. 10, 2025 Researchers have uncovered surprising evidence that the deep ocean’s carbon-fixing engine works very differently than long assumed. While ammonia-oxidizing archaea were thought to dominate carbon ...
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