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Sources
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Sunspots FAQ
What causes a sunspot?
Sunspots occur because the interior and exterior of the sun rotate separately; the outside rotates more quickly at the equator than at the solar north and south poles. Over time, that uneven movement twists and distorts the sun's main magnetic field. This creates spots that have so much magnetic power that they push back the hot gases beneath them and prevent the heat from rising directly to the surface, creating sunspots.
What is the frequency of the sunspot cycle?
Roughly every 11 years, the number of sunspots increases from nearly zero to more than 100 and then decreases to near zero again as a new cycle starts. This pattern is called the sunspot cycle.
What causes the sunspot cycle?
The sunspot cycle occurs because the sun contains a sort of conveyor belt that circulates a hot, electrified gas called plasma between the sun's equator and its poles and then back again over a period of years.
Do sunspots affect climate?
It's unclear if there's a link between solar weather and changes in Earth's climate because our planet's climate is influenced by so many other factors, from volcanic eruptions to man-made emissions of greenhouse gases.
How long does a sunspot last?
An individual sunspot can last anywhere from a few days to a few months.