In principle, this process seemed to be similar in the north and the south. In 2009, however, it was found that the northern and southern lights differed considerably: one of them takes a few hours later than the other, their widths and directions differ in the sky. Now a new analysis of observation data helps to find out what makes the difference.
The magnetic field carried by the solar wind is usually directed to the east-west, i. perpendicular to the magnetic axis of the earth. The interaction with the magnetosphere of the earth seems asymmetrical and disturbs the magnetic field of our planet. In one hemisphere a collection of banana-shaped magnetic lines is formed and in the other a similar mass in the form of a circle. This uneven distribution of the magnetic field also influences the appearance of light.
It is true that the magnetosphere tail – opposite the sun on the earth side – can merge and level the magnetic field lines; so the asymmetry of the light is slightly reduced.