News tagged with air
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.
For more information about Earth's atmosphere, read the full article at
Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.
Low speed wind tunnel gets new motor
A new motor has been installed in the Oran W. Nicks Low Speed Wind Tunnel, replacing a 900RPM, 1,000-horsepower synchronous motor from Allis-Chalmers that was surplused by the U.S. Navy back in World War II.
14 hours ago |
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Key facts about SpaceX
Space Exploration Technologies is the first private company to attempt to send its own cargo capsule to the International Space Station and back.
Space & Earth / Space Exploration
May 22, 2012 |
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Beetle-infested pine trees contribute more to air pollution and haze in forests
The hordes of bark beetles that have bored their way through more than 6 billion trees in the western U.S. and British Columbia since the 1990s do more than damage and kill stately pine, spruce and other trees. ...
May 23, 2012 |
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