The magnetic field of the Sun is constantly changing, and it occasionally produces magnetic knots that are the equivalent of a twist in a rubber band. These knots can disrupt the flow of hot plasma in the Sun's interior, causing it to cool and sink below the surface. This creates a region of lower pressure that allows hotter plasma from below to rise up, pushing cooler plasma down and creating a sunspot.
The presence of sunspots is correlated with increased solar activity, including solar flares and coronal mass ejections. Solar flares are powerful bursts of energy that can disrupt radio communications and damage satellites. Coronal mass ejections are the expulsion of large amounts of plasma from the Sun's corona, which can create geomagnetic storms on Earth.
The number of sunspots changes over time in a cyclical manner known as the solar cycle. The solar cycle lasts for about 11 years, and it has a peak and a trough. During the peak of the solar cycle, the Sun produces more sunspots and increased solar activity. During the trough, the Sun produces fewer sunspots and less solar activity.
The most recent solar cycle, known as Solar Cycle 24, began in 2008 and is expected to peak in 2024-2025.
