The Sun and Solar Geometry

  • J. R. Simonson


The Sun is but one of a vast number of stars within the Milky Way Galaxy and it contains over 99 per cent of the matter within the Solar System The Sun has a surface temperature of approximately 5760 K and emits radiant energy at the rate of 380 × 1015 GW. The Earth travels round the Sun in 365¼ days with the axis of rotation of the Earth at an angle of 23.45° to the plane of rotation around the Sun, which results in seasonal changes in the illumination of the Earth. In addition the path of the Earth around the Sun is slightly elliptical, so that the intensity of solar radiation outside the Earth’s atmosphere, the Solar Constant, varies slightly throughout the year.


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Copyright information

© J. R. Simonson 1984

Authors and Affiliations

  • J. R. Simonson
    • 1
  1. 1.Department of Mechanical EngineeringThe City UniversityLondonUK

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