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  2. Stellar atmosphere - Wikipedia

    en.wikipedia.org/wiki/Stellar_atmosphere

    The outermost part of the stellar atmosphere, or upper stellar atmosphere, is the corona, a tenuous plasma which has a temperature above one million Kelvin. [6] While all stars on the main sequence feature transition regions and coronae, not all evolved stars do so. It seems that only some giants, and very few supergiants, possess coronae.

  3. Atmosphere of Earth - Wikipedia

    en.wikipedia.org/wiki/Atmosphere_of_Earth

    The troposphere is the lowest layer of Earth's atmosphere. It extends from Earth's surface to an average height of about 12 km (7.5 mi; 39,000 ft), although this altitude varies from about 9 km (5.6 mi; 30,000 ft) at the geographic poles to 17 km (11 mi; 56,000 ft) at the Equator, [17] with some variation due

  4. COSPAR International Reference Atmosphere - Wikipedia

    en.wikipedia.org/wiki/COSPAR_international...

    The COSPAR International Reference Atmosphere (CIRA) is an empirical model of the atmosphere of Earth. It consists of a set of tables of average air pressures, altitudes and temperatures. The CIRA models are developed by the Committee on Space Research (COSPAR) and have been important for the planning of spaceflight. [1] [2]

  5. Atmosphere - Wikipedia

    en.wikipedia.org/wiki/Atmosphere

    A stellar atmosphere is the outer region of a star, which includes the layers above the opaque photosphere; stars of low temperature might have outer atmospheres containing compound molecules. The atmosphere of Earth is composed of nitrogen (78%), oxygen (21%), argon (0.9%), carbon dioxide (0.04%) and trace gases. [2]

  6. Scientists confirm 'Earth-like' planet with atmosphere ... - AOL

    www.aol.com/news/2017-04-07-scientists-confirm...

    The discovery that GJ 1132b has an atmosphere is a key step in the search for life outside our solar system. Scientists confirm 'Earth-like' planet with atmosphere discovered 39 light-years from Earth

  7. Van Allen radiation belt - Wikipedia

    en.wikipedia.org/wiki/Van_Allen_radiation_belt

    Earth has two such belts, and sometimes others may be temporarily created. The belts are named after James Van Allen, who published an article describing the belts in 1958. [1] [2] Earth's two main belts extend from an altitude of about 640 to 58,000 km (400 to 36,040 mi) [3] above the surface, in which region radiation levels vary.

  8. Grey atmosphere - Wikipedia

    en.wikipedia.org/wiki/Grey_atmosphere

    The grey atmosphere (or gray) is a useful set of approximations made for radiative transfer applications in studies of stellar atmospheres (atmospheres of stars) based on the simplified notion that the absorption coefficient of matter within a star's atmosphere is constant—that is, unchanging—for all frequencies of the star's incident radiation.

  9. Earth - Wikipedia

    en.wikipedia.org/wiki/Earth

    Earth has a dynamic atmosphere, which sustains Earth's surface conditions and protects it from most meteoroids and UV-light at entry. It has a composition of primarily nitrogen and oxygen. Water vapor is widely present in the atmosphere, forming clouds that cover most of the planet.