Business

German air force rejects delivery of two Airbus planes

Germany's air force said Wednesday it had refused delivery of two Airbus A400M transport planes over technical faults, saying bolts holding the propellers on some already operational aircraft were loose.

Engineering

New Low-Load Cycle targets heavy-duty diesel engine emissions

Southwest Research Institute engineers developed a new certification cycle, the Low-Load Cycle (LLC), to gauge the performance of heavy-duty diesel engine aftertreatment systems in low-load conditions. Aftertreatment systems ...

Business

Air France must capitalise on home market: AF-KLM chief

Air France has resolved difficult staff relations that led to debilitating strikes and must now reposition itself in the ultra-competitive airline industry to take advantage of its home turf, according to Ben Smith, the head ...

Business

IAG buys Air Europa amid aviation sector upheaval

British Airways owner IAG agreed Monday to buy Spain's Air Europa as the global aviation sector charts a path through high-profile failures, fierce competition, economic woes and high fuel prices.

Internet

Predicting pollution with internet of things

Recent research suggests that heart attacks, cerebral stroke, and asthma attacks all rise with increasing air pollution in our cities, and of course the wider problems for the environment and human, animal, and plant life ...

Telecom

When WiFi is weak, send noise instead

When WiFi was designed, it was intended for high-speed data communications. The Institute of Electrical and Electronics Engineers (IEEE) set the standards for communications—that's the 802.11 protocol, a familiar number ...

Business

Indonesia's Lion air set to list shares

Indonesia's Lion Air is set to launch an initial public offering, according to a company spokesman, in a listing that could reportedly raise up to $1.0-billion—one of the country's biggest-ever share sales.

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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