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  2. Photosphere - Wikipedia

    en.wikipedia.org/wiki/Photosphere

    The Sun is composed primarily of the chemical elements hydrogen and helium; they account for 74.9% and 23.8%, respectively, of the mass of the Sun in the photosphere.All heavier elements, colloquially called metals in stellar astronomy, account for less than 2% of the mass, with oxygen (roughly 1% of the Sun's mass), carbon (0.3%), neon (0.2%), and iron (0.2%) being the most abundant.

  3. Stellar atmosphere - Wikipedia

    en.wikipedia.org/wiki/Stellar_atmosphere

    The photosphere, which is the atmosphere's lowest and coolest layer, is normally its only visible part. [1] Light escaping from the surface of the star stems from this region and passes through the higher layers. The Sun's photosphere has a temperature in the 5,770–5,780 K (5,500–5,510 °C; 9,930–9,940 °F) range.

  4. Stellar corona - Wikipedia

    en.wikipedia.org/wiki/Stellar_corona

    Between the photosphere and the corona, the thin region through which the temperature increases is known as the transition region. It ranges from only tens to hundreds of kilometers thick. Energy cannot be transferred from the cooler photosphere to the corona by conventional heat transfer as this would violate the second law of thermodynamics.

  5. Chromosphere - Wikipedia

    en.wikipedia.org/wiki/Chromosphere

    The red color of the chromosphere could be seen during the solar eclipse of August 11, 1999.. The density of the Sun's chromosphere decreases exponentially with distance from the center of the Sun by a factor of roughly 10 million, from about 2 × 10 −4 kg/m 3 at the chromosphere's inner boundary to under 1.6 × 10 −11 kg/m 3 at the outer boundary. [7]

  6. Sun - Wikipedia

    en.wikipedia.org/wiki/Sun

    The spectrum of sunlight has approximately the spectrum of a black-body radiating at 5,772 K (9,930 °F), [12] interspersed with atomic absorption lines from the tenuous layers above the photosphere. The photosphere has a particle density of ~10 23 m −3 (about 0.37% of the particle number per volume of Earth's atmosphere at sea level). The ...

  7. Tyler’s 1983 hit “Total Eclipse of the Heart” topped the charts in several countries and went on to help define the sound of the ’80s, but in a Monday, November 27, interview, Tyler shared ...

  8. Model photosphere - Wikipedia

    en.wikipedia.org/wiki/Model_photosphere

    The photosphere denotes those solar or stellar surface layers from which optical radiation escapes. These stellar outer layers can be modeled by different computer programs. Often, calculated models are used, together with other programs, to calculate synthetic spectra for stars. For example, in varying the assumed abundance of a chemical ...

  9. Pericardium - Wikipedia

    en.wikipedia.org/wiki/Pericardium

    The pericardium (pl.: pericardia), also called pericardial sac, is a double-walled sac containing the heart and the roots of the great vessels. [1] It has two layers, an outer layer made of strong inelastic connective tissue (fibrous pericardium), and an inner layer made of serous membrane (serous pericardium).