Supergranulation

Supegranulation in the chromosphere of Sun.

In solar physics and observation, supergranulation is a pattern of convection cells in the Sun's photosphere. The individual convection cells are typically referred to as supergranules. The pattern was discovered in the 1950s by A.B. Hart^[1] using Doppler velocity measurements showing horizontal flows on the photosphere (flow speed about 300 to 500 m/s, a tenth of that in the smaller granules). Later work (1960s) by Leighton, Noyes and Simon established a typical size of about 30000 km for supergranules with a lifetime of about 24 hours.^[2]

^ Hart, A. B. (1 February 1956). "Motions in the Sun at the Photospheric Level: VI. Large-Scale Motions in the Equatorial Region". Monthly Notices of the Royal Astronomical Society. 116 (1): 38–55. doi:10.1093/mnras/116.1.38.
^ Freedman, Roger A.; Kaufmann III, William J. (2008). Universe. New York, USA: W. H. Freeman and Company. pp. 762. ISBN 978-0-7167-8584-2.

[1] Hart, A. B. (1 February 1956). "Motions in the Sun at the Photospheric Level: VI. Large-Scale Motions in the Equatorial Region". Monthly Notices of the Royal Astronomical Society. 116 (1): 38–55. doi:10.1093/mnras/116.1.38.

[Freedman-2] Freedman, Roger A.; Kaufmann III, William J. (2008). Universe. New York, USA: W. H. Freeman and Company. pp. 762. ISBN 978-0-7167-8584-2.

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