The causes of sunspots are not understood, but there is an idea put forward by Paul Jose in 1947 that connects their numbers at any time with the position of the Sun with respect to the centre of gravity [centre of mass] of the solar system. This section gives an example of the calculations.

The centre of gravity or centre of mass of a collection of objects is given by calculating the value of its three coordinates, x, y and z such that the values of the sums: S(x - x')m, S(y - y')m, S(z - z')m are all equal to zero. The x', y' and z' components are the respective coordinates of the participating bodies and the m's are their respective masses.

In the diagram the yellow circle represents the Sun with its radius of 6.96 x 105 km. The curve begins with the 1970 position [middle left of the diagram] of the centre of mass of the solar system, i.e., the planets and the Sun, just on the edge of the Sun. From there it takes a tight anti-clockwise curving bend to the 1980 position, well outside the sun's body. The rest of the track is reasonably clear except the ending in 2020 which is almost coincident with that of 1995.

These positions are known with considerable accuracy and if there is a connection between the trajectory of the centre of mass of the solar system and the intensity of sunspots there is the possibility of the theory having some prediction value and is therefore testable against future observations.

The basis idea is that if the centre of mass of the solar system does not coincide with that of the sun itself the planets can have an effect on the internal arrangement of the sun. If the changes are releatively rapid the sun's interior could get churned up and possibly induce more sunspots than if the changes are gentle.

If the sunspot/centre of gravity theory does recieve confirmation it would assist the idea of the connection between the sunspot intensity and that of the solar wind, which in turn would be of assistance with the cosmic ray shielding theory.

We shall see!

A newly revised treatment of the influence of the solar system on climate has been published.