Definition
The Sun is the central body of our solar system and the nearest star. It is a low-mass star of spectral type G2 V located on the main sequence in the Hertzsprung-Russell diagram, with an age of about 4.6 billion years. Its mass is 1.99 × 1030 kg and its bolometric luminosity amounts to 3.84 × 1026 W. The Sun shows diverse signs of magnetic activity, in particular sunspots, a warm chromosphere, a very hot magnetic corona, flares, coronal mass ejections, and the solar wind.
Overview
The Sun is a main-sequence star in the phase of core hydrogen burning, being in the midst of the longest stable phase of stellar evolutionbefore the white dwarf phase. It is a metal-rich (population I) star with an age of approximately 4.6 billion years. It will spend another ≈5 Gyr before evolving off the main sequence. The Sun is classified as a low-mass star of spectral type G2. It entirely dominates the solar system in terms of mass and energy. Its luminosity is such that at the distance of...
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Güdel, M. (2023). Sun (and Young Sun). In: Gargaud, M., et al. Encyclopedia of Astrobiology. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-662-65093-6_1542
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DOI: https://doi.org/10.1007/978-3-662-65093-6_1542
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