Related topics: nasa · climate change · solar wind · mars · solar radiation

Scientists map Mars' global wind patterns for the first time

Today, a paper published in Science documents for the first time the global wind circulation patterns in the upper atmosphere of a planet, 120 to 300 kilometers above the surface. The findings are based on local observations, ...

ESA's Mars orbiters did not see latest Curiosity methane burst

In June, NASA's Curiosity rover reported the highest burst of methane recorded yet, but neither ESA's Mars Express nor the ExoMars Trace Gas Orbiter recorded any signs of the illusive gas, despite flying over the same location ...

Distant 'heavy metal' gas planet is shaped like a football

The scorching hot exoplanet WASP-121b may not be shredding any heavy metal guitar riffs, but it is sending heavy metals such as iron and magnesium into space. The distant planet's atmosphere is so hot that metal is vaporizing ...

Twin NASA satellites to study signal disruption from space

NASA's twin E-TBEx CubeSats—short for Enhanced Tandem Beacon Experiment—are scheduled to launch in June 2019 aboard the Department of Defense's Space Test Program-2 launch. The launch includes a total of 24 satellites ...

New water cycle on Mars discovered

Approximately every two Earth years, when it is summer on the southern hemisphere of Mars, a window opens: Only in this season can water vapor efficiently rise from the lower into the upper Martian atmosphere. There, winds ...

Scientists discover what powers celestial phenomenon STEVE

The celestial phenomenon known as STEVE is likely caused by a combination of heating of charged particles in the atmosphere and energetic electrons like those that power the aurora, according to new research. In a new study, ...

ESA's space weather mission to be protected against stormy sun

ESA is planning Earth's first dedicated space weather observatory to warn of potentially harmful turbulence in our parent star. Like a referee at a sports game, the Lagrange spacecraft will be able to observe both the sun ...

NASA selects mission to study space weather from space station

NASA has selected a new mission that will help scientists understand and, ultimately, forecast the vast space weather system around our planet. Space weather is important because it can have profound impacts – affecting ...

Image: From Earth with love

"Valentine's Day has struck again," tweeted ESA astronaut Thomas Pesquet when he posted this image of a heart-shaped lake in Mongolia. Thomas took this image from the International Space Station during his Proxima mission ...

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Earth's atmosphere

The Earth's atmosphere is a layer of gases surrounding the planet Earth that is retained by the Earth's gravity. It has a mass of about five quadrillion metric tons. Dry air contains roughly (by volume) 78.08% nitrogen, 20.95% oxygen, 0.93% argon, 0.038% carbon dioxide, and trace amounts of other gases. Air also contains a variable amount of water vapor, on average around 1%. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night.

There is no definite boundary between the atmosphere and outer space. It slowly becomes thinner and fades into space. An altitude of 120 km (75 mi) marks the boundary where atmospheric effects become noticeable during atmospheric reentry. The Kármán line, at 100 km (62 mi), is also frequently regarded as the boundary between atmosphere and outer space. Three quarters of the atmosphere's mass is within 11 km (6.8 mi; 36,000 ft) of the surface.

This text uses material from Wikipedia, licensed under CC BY-SA