The Sun’s surface features vary in an 11-year cycle

• The Sun’s surface features vary in an 11-year cycle

• This is related to a 22-year cycle in which the surface magnetic field increases, decreases, and then increases again with the opposite polarity

• The average number of sunspots increases and decreases in a regular cycle of approximately 11 years, with reversed magnetic polarities from one 11-year cycle to the next

• Two such cycles make up the 22-year solar cycle