<P> The solar cycle or solar magnetic activity cycle is the nearly periodic 11 - year change in the Sun 's activity ( including changes in the levels of solar radiation and ejection of solar material ) and appearance ( changes in the number and size of sunspots , flares , and other manifestations ) . </P>
<P> The solar cycle or solar magnetic activity cycle is the nearly periodic 11 - year change in the Sun 's activity ( including changes in the levels of solar radiation and ejection of solar material ) and appearance ( changes in the number and size of sunspots , flares , and other manifestations ) . </P>
what is the length of the sunspot cycle
what is the length of the sunspot cycle
nearly periodic 11 - year change
nearly periodic 11 - year change