Publication Abstracts
Chiu 1966
Chiu, H.-Y., 1966: The evolution of the Sun. Ann. New York Acad. Sci., 140, no. 1, 35-45, doi:10.1111/j.1749-6632.1966.tb50942.x.
The sun, being the star nearest to us, is the only one whose disc can be resolved and whose outer structure can be studied with great precision. Yet despite its proximity, only a small amount of information regarding the past history and the future course of evolution of the sun comes from direct observation. Most knowledge about the evolution of the sun comes from indirect reasoning from planetary observations and from comparing the sun with other stars, which are so distant that they appear as points of light even in the largest telescope.
T o the naked eye, the sun appears to be a strongly illuminated disc with an angular diameter of 30 minutes of arc. Although during solar eclipse the sun is seen to possess an extended outer envelope known as the corona, which extends to several solar radii from the surface of the sun, the mass of the corona is only a minute fraction of the entire mass.
Although the corpuscular radiation from the sun, in the form of solar cosmic rays and solar wind, can seriously affect the condition of the earth's ionosphere and magnetosphere, the energy of these particles is insignificant compared to the total energy radiated by the sun. At the surface of the earth, each square centimeter of area receives two calories of energy per minute, enough to raise the temperature of one gram of water by two degrees per minute. The sun is therefore the main source of energy to the earth. At present, the energy output rate is surprisingly constant, and so far no variations in the luminosity of the sun have been detected.
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BibTeX Citation
@article{ch02510w,
author={Chiu, H.-Y.},
title={The evolution of the Sun},
year={1966},
journal={Annals of the New York Academy of Sciences},
volume={140},
number={1},
pages={35--45},
doi={10.1111/j.1749-6632.1966.tb50942.x},
}
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RIS Citation
TY - JOUR ID - ch02510w AU - Chiu, H.-Y. PY - 1966 TI - The evolution of the Sun JA - Ann. New York Acad. Sci. JO - Annals of the New York Academy of Sciences VL - 140 IS - 1 SP - 35 EP - 45 DO - 10.1111/j.1749-6632.1966.tb50942.x ER -
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