Term: | Sun Spots |
Definition: |
Dark areas on the solar surface that contain constantly shifting strong magnetic fields. An average sunspot is about as large as Earth and it moves along with the sun's rotation, lasting for days or even weeks. The magnetic activity in sunspots can give rise to various solar eruptive events such as flares and coronal mass ejections (CMEs). The number of sunspots on the sun wax and wane over approximately an 11-year cycle, thus defining what is called the solar cycle. They appear dark since they are cooler than the surrounding solar material. |