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from Wikipedia, the free encyclopedia

Earth's atmosphere

Earth's atmosphere is a layer of gases surrounding the planet Earth and retained by the Earth's gravity. It contains roughly 78% nitrogen and 21% oxygen 0.97% argon and carbon dioxide 0.04% trace amounts of other gases, and water vapor. This mixture of gases is commonly known as air. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation and reducing temperature extremes between day and night.

The atmosphere has no abrupt cut-off. It slowly becomes thinner and fades away into space. There is no definite boundary between the atmosphere and outer space. Three-quarters of the atmosphere's mass is within 11 km of the planetary surface..

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Earth & Climate News

July 19, 2026

The asteroid that wiped out the dinosaurs was likely an exceptionally rare CO chondrite from a distant region of the solar system. Its unusual chemistry suggests that planet-cooling dust and debris, ...
Scientists have found evidence that a major Cascadia earthquake could trigger a second quake on the San Andreas Fault. The discovery came from unusual sediment layers formed by underwater landslides ...
A catastrophic asteroid breakup may have triggered a huge wave of impacts across the inner solar system about 800 million years ago. The debris was launched from near a gravitational gateway controlled by Jupiter, sending fragments toward Earth, the ...
Seismic waves have revealed that the oceanic plate beneath the Ontong Java Plateau was dramatically transformed by the colossal volcanic activity that created it more than 100 million years ago. Researchers found a complex structure of horizontal ...
Tiny plastic particles in drinking water may be doing more than contaminating the environment. New research suggests nanoplastics can actually help harmful bacteria survive by strengthening the slimy biofilms they form inside water systems. These ...
A major DNA study has rewritten the koala's evolutionary story, revealing that the species suffered a dramatic population collapse about 100,000 years ago, long before humans arrived in Australia. By calculating the koala's mutation rate for the ...
Researchers have created self-destructing living plastic that uses engineered bacteria to completely break itself down when activated. The material degrades in just six days without creating ...
Scientists have identified a hidden feedback loop that may explain how Earth has regulated its climate for tens of millions of years. As sea levels rose and fell, they changed how much phosphate reached the open ocean, affecting marine life and the ...
NASA's PACE satellite captured the Black Sea glowing turquoise during its annual phytoplankton bloom. The vivid color comes from massive numbers of coccolithophores, microscopic organisms whose reflective shells brighten the water enough to be seen ...
The world's longest-running soil warming experiment has revealed an unexpected climate concern. After nearly four decades, researchers found that warming can cause microbes to break down stable soil carbon that scientists once believed was largely ...
Scientists discovered that extreme deep-sea pressure squeezes valuable nutrients out of sinking organic particles, providing an unexpected food source for ocean microbes. The finding could rewrite our understanding of both deep-ocean ecosystems and ...
Why do beaches today have seashells from clams and snails instead of brachiopods? A new study suggests the answer lies in Earth's greatest mass extinction, when warming oceans and falling oxygen levels wiped out animals that couldn't adapt. Species ...

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