When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Atmosphere of Earth - Wikipedia

    en.wikipedia.org/wiki/Atmosphere_of_Earth

    The atmosphere has a mass of about 5.15 × 10 18 kg, [3] three quarters of which is within about 11 km (6.8 mi; 36,000 ft) of the surface. The atmosphere becomes 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 ...

  3. Nitrogen - Wikipedia

    en.wikipedia.org/wiki/Nitrogen

    Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at seventh in total abundance in the Milky Way and the Solar System. At standard temperature and pressure, two atoms of the element bond to form N 2, a colorless and odorless diatomic gas.

  4. Atmosphere - Wikipedia

    en.wikipedia.org/wiki/Atmosphere

    The atmosphere of Earth is composed of nitrogen (78%), oxygen (21%), argon (0.9%), carbon dioxide (0.04%) and trace gases. [2] Most organisms use oxygen for respiration ; lightning and bacteria perform nitrogen fixation which produces ammonia that is used to make nucleotides and amino acids ; plants , algae , and cyanobacteria use carbon ...

  5. Atmosphere of Pluto - Wikipedia

    en.wikipedia.org/wiki/Atmosphere_of_Pluto

    0.0001%. Hydrogen cyanide (HCN) 10 -5 -10 -6 %. The atmosphere of Pluto is the layer of gasses that surround the dwarf planet Pluto. It consists mainly of nitrogen (N 2), with minor amounts of methane (CH 4) and carbon monoxide (CO), all of which are vaporized from surface ices on Pluto 's surface. It contains layered haze, probably consisting ...

  6. Atmosphere of Mars - Wikipedia

    en.wikipedia.org/wiki/Atmosphere_of_Mars

    The atmosphere of Mars is the layer of gases surrounding Mars. It is primarily composed of carbon dioxide (95%), molecular nitrogen (2.85%), and argon (2%). [3] It also contains trace levels of water vapor, oxygen, carbon monoxide, hydrogen, and noble gases. [3][5][2] The atmosphere of Mars is much thinner and colder than Earth's having a max ...

  7. Density of air - Wikipedia

    en.wikipedia.org/wiki/Density_of_air

    Air density, like air pressure, decreases with increasing altitude. It also changes with variations in atmospheric pressure, temperature and humidity. At 101.325 kPa (abs) and 20 °C (68 °F), air has a density of approximately 1.204 kg/m 3 (0.0752 lb/cu ft), according to the International Standard Atmosphere (ISA).

  8. Nitrogen cycle - Wikipedia

    en.wikipedia.org/wiki/Nitrogen_cycle

    The nitrogen cycle is an important process in the ocean as well. While the overall cycle is similar, there are different players [40] and modes of transfer for nitrogen in the ocean. Nitrogen enters the water through the precipitation, runoff, or as N 2 from the atmosphere. Nitrogen cannot be utilized by phytoplankton as N

  9. Atmosphere of the Moon - Wikipedia

    en.wikipedia.org/wiki/Atmosphere_of_the_Moon

    Argon-40, helium-4, oxygen and/or methane (CH 4), nitrogen (N 2) and/or carbon monoxide (CO), and carbon dioxide (CO 2)) were detected by in-situ detectors placed by the Apollo astronauts. [10] The average daytime abundances of the elements known to be present in the lunar atmosphere, in atoms per cubic centimeter, are as follows: Argon: 20,000 ...