Before its recent eruptions, the sun showed signs that something big was coming. Cooler areas, called sunspots, formed on its surface.
Sunspots are created by the sun’s extremely strong magnetic field. The spots usually come in pairs. They tend to form at places where the sun’s constantly changing magnetic field creates north and south poles. The field is like a rubber band that twists and stretches out from the sun’s surface until it suddenly snaps. That releases an explosion of energy as a solar flare.
The September eruption disrupted radio communications on Earth for about an hour. Flares can also affect power grids. Some interact with Earth’s magnetic field to create bands of light known as auroras in the skies near the poles.