Sun Spots


Solar Wind

Solar Magnetic Mean Field


The Solar Magnetic Mean Field (SMMF), mainly caused by the sunspots, is measured on the entire solar surface. In its progression, the 11 year solar cycle can be recognised. Since also other phenomena contribute to its total value, the 27 day period of the solar rotation becomes apparent. The SMMF changes according to the predominant polarity of the magnetic field and can therefore become negative, whereas the sun spot number always stays positive.
The data used here are daily averages from the Wilcox Solar Observatory and can be obtained from the following website "".

In the image, the Solar Magnetic Meanfield can be recognized as a circle, changing its size according to the measured value and thus defining a boarder between the ordered grid and the disarranged structure. Additionally the 27 day average is shown as a second circle, showing its value by a change of colour. Interpolated values are indicated by a point in the centre of the image.


The value of the Solar Magnetic Meanfield changes the sound of a double bass, which is played by the data of the solar wind. The principle is similar to the sonification of the Irradiance; the higher the measured value, the stronger the alteration.