Solar cycles regulate all solar activity and space weather. Although they have been studied a lot in recent decades, they are not yet fully known.
It is very important to understand how solar cycles work, since they affect a large part of our current technology and, above all, communications and air navigation. It is also necessary to plan future missions to Mars.
The Sun works at a constant and orderly pace. The solar cycle is related to the appearance of sunspots. In the nineteenth century it was discovered that every 11 years mysterious spots appeared on the surface of the Sun. Today we know that sunspots indicate the maximum solar, that is, the moment when the Sun has more activity.
Each solar cycle lasts 11 years. The responsible is the magnetic field of the Sun, and this is produced by the movement of the plasma inside.
Plasma moves at different speeds in different areas of the Sun, like this:
• In the outer layers of the Sun (convective and photosphere areas): in the area of the equator the plasma takes 26 days to make a complete turn. While the plasma near the poles moves more slowly and takes 36 days.
• In the inner layers of the Sun (nucleus and radioactive zone): It takes 27 days for the plasma to complete a round.
Therefore, the plasma of the inner layers moves more slowly than that of the outer layers of the equator, but much faster than that of the poles. This speed difference causes some layers to slide over others and create a magnetic field. Sunspots are areas where the magnetic field is strongest.
The magnetic field is formed by electrically charged particle lines. At the beginning of the cycle, these lines are ordered from pole to pole. The plasma, when moving, pushes and bends them. As the plasma moves at different speeds, the magnetic field lines twist, bend and rise until they surface. They go outside in the form of coronal loops, which can reach the height of several planets Earth.
When the solar activity is maximum, the loops are very numerous and intense. They collide with each other and expel huge jets of plasma and X-rays, called flares. The plasma expands throughout the Solar System and forms the solar wind.
Sometimes they occur coronal mass ejections, violent plasma explosions that are the origin of solar storms.
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