Sunspot activity tends to follow a cycle of roughly:
A) 30 years.
B) 500 years.
C) 11 years.
D) 100 years.
E) 26,000 years.

Question

Quizplus · Accepted Answer

Sunspot activity tends to follow a cycle of approximately 11 years. This cycle is known as the solar cycle or the sunspot cycle. During this cycle, the number of sunspots and solar flares increase and decrease in a predictable pattern. This cycle has been studied and observed for hundreds of years, and is thought to be related to changes in the magnetic fields of the sun.

Sunspot Activity Tends to Follow a Cycle of Roughly