Atmosphere of Earth

The atmosphere of Earth is the layer of gases surrounding the planet Earth that is retained by Earth's gravity. 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 (the diurnal temperature variation).

The common name air (English pronunciation: /ɛər/) is given to the atmospheric gases used in breathing and photosynthesis. By volume, dry air contains 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.039% carbon dioxide, and small amounts of other gases. Air also contains a variable amount of water vapor, on average around 1% at sea level, and 0.4% over the entire atmosphere. Air content and atmospheric pressure vary at different layers, and air suitable for the survival of terrestrial plants and terrestrial animals is found only in Earth's troposphere and artificial atmospheres.

The atmosphere has a mass of about 5.15×10¹⁸ kg, three quarters of which is within about 11 km (6.8 mi; 36,000 ft) of the surface. The atmosphere becomes thinner and thinner with increasing altitude, with no definite boundary between the atmosphere and outer space. The Kármán line, at 100 km (62 mi), or 1.57% of Earth's radius, is often used as the border between the atmosphere and outer space. Atmospheric effects become noticeable during atmospheric reentry of spacecraft at an altitude of around 120 km (75 mi). Several layers can be distinguished in the atmosphere, based on characteristics such as temperature and composition.

Nam

Nam or NAM may refer to:

Geography

Organizations

Popular culture

Science and technology

Sriwijaya Air

Sriwijaya Air is an Indonesian airline based in Jakarta with its headquarters located at Soekarno-Hatta International Airport M1 Area in Tangerang, near Jakarta. Sriwijaya Air is the country's third largest carrier, operating a fleet of narrow-body aircraft and offers flights to various Indonesian destinations and a few international destinations. The airline is listed as a Category 1 airline by Indonesia's Civil Aviation Authority, the highest status that can be achieved for operational safety.

History

In 2003, Sriwijaya Air was founded by Chandra Lie, Hendry Lie, Andi Halim and Fandy Lingga, who named it after the historical Srivijaya empire. That same year, on April 28, it obtained its business license, while the AOC (Air Operator's Certificate) was issued later that year on October 28. Commencing operations on 10 November 2003, the airline initially launched flights between Jakarta and Pangkal Pinang, before introducing new routes such as Jakarta-Pontianak and Jakarta-Palembang. In its first year, Sriwijaya Air experienced rapid growth, and by June 2009, Sriwijaya Air was operating 23 aircraft, serving more than 33 domestic and 2 international routes.

Boeing 737 Classic

The Boeing 737 Classic is the -300/-400/-500 series of the Boeing 737, so named following the introduction of the -600/-700/-800/-900 series. They are short- to medium- range, narrow-body jet airliners produced by Boeing Commercial Airplanes. The Classic series was introduced as the 'new generation' of the 737. Produced from 1984 to 2000, 1,988 aircraft were delivered.

Development and design

Following the success of the Boeing 737-200 Advanced, Boeing wanted to increase capacity and range, incorporating improvements to upgrade the plane to modern specifications, while also retaining commonality with previous 737 variants. Development began in 1979, and in 1980 preliminary aircraft specifications were released at the Farnborough Airshow. In March 1981, USAir and Southwest Airlines each ordered 10 aircraft, with an option for 20 more.

The new series featured CFM56 turbofan engines, yielding significant gains in fuel economy and a reduction in noise, but also posing an engineering challenge given the low ground clearance of the 737. Boeing and engine supplier CFMI solved the problem by placing the engine ahead of (rather than below) the wing, and by moving engine accessories to the sides (rather than the bottom) of the engine pod, giving the 737 a distinctive non-circular air intake.

International airport

An international airport is an airport that offers customs and immigration facilities for passengers travelling between countries. International airports are typically larger than domestic airports and often feature longer runways and facilities to accommodate the heavier aircraft commonly used for international and intercontinental travel. International airports often also host domestic flights. Some, such as Frankfurt Airport in Germany are very large; others such as Fa'a'ā International Airport in Tahiti, are quite small.

Buildings, operations and management have become increasingly sophisticated since the mid 20th century, when international airports began to provide infrastructure for international civilian flights. Detailed technical standards have been developed to ensure safety and common coding systems implemented to provide global consistency. The physical structures that serve millions of individual passengers and flights are among the most complex and interconnected in the world. By the second decade of the 21st century, there were over 1,200 international airports and almost two billion international passengers along with 50 million metric tonnes of cargo were passing through them annually.