Related topics: air pollution · air quality · pollution

Eight CubeSats lift off for NASA on Firefly Aerospace rocket

As part of NASA's CubeSat Launch Initiative, Firefly Aerospace launched eight small satellites on July 3 aboard the company's Alpha rocket. Named "Noise of Summer," the rocket successfully lifted off from Space Launch Complex ...

Study reveals fireworks' impact on air quality

As Independence Day approaches, Utahns are preparing to celebrate the nation's birth with dazzling displays of light and color. However, a new BYU study published in Applied Geochemistry warns that these festivities come ...

Study finds emissions trading also creates health benefits

The EU Emissions Trading System is not only good for reducing CO2 and for the climate. It also results in considerable health benefits due to reduced air pollution and saves hundreds of billions of euros, according to a recently ...

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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