Solar Activity - 2

Sunspots are temporary regions of reduced surface temperature caused by increased magnetic activity. The Sun goes through a cycle of about 11 years when it has a period of many sunspots (solar maximum), then few or no sunspots (solar minimum). Sunspots or similar magnetically active regions are the source of solar storms. The Sun’s magnetic fields are constantly in motion. When solar magnetic fields twist, break, and then reconnect, they can release a tremendous amount of energy. We see these as solar flares, like the white brightening near the center of the image on the right. Solar flares eject radiation and fast moving particles that can damage satellites, disrupt communications, and give high-flying planes and astronauts additional doses of radiation. Finding ways to protect astronauts from solar flares is one of the biggest challenges of going back to the Moon or to Mars.