Sunspot

This is the Sun on January 6, 2014 with a "small" area at about ten o'clock off center. That is a sunspot about the size of the earth. Sunspots were not discovered until the 1970s but this one is huge and can be seen by the naked eye.  A sunspot is a release of energy from the Sun, explosions called "coronal mass ejections," in gigantic proportion in the form of solar particles, the "solar wind." These energetic particles arrive at the Earth (or Moon) about an hour later. (The high energy particles arrive at earth in eight minutes.) The actual coronal mass ejection arrives at the Earth one to four days after the initial eruption, resulting in strong geomagnetic storms, aurorae and  electrical power blackouts. That would be tomorrow, January 9.