The activity followed a pair of flares last week that passed by the planet Friday and Saturday. Despite warnings that communication systems might suffer, no damage was reported to satellites in space or power systems on the ground.

The latest storms are part of a series of energetic coronal mass ejections, in which twisted magnetic fields on the Sun cut loose and throw bubbles of superheated gas, called plasma, into space.

The storms could generate colorful lights, called aurora, at lower latitudes than normal. The aurora are created with solar storms penetrate Earth's natural defense -- a magnetic field that extends beyond the atmosphere. Charged particles from the Sun getting through the defenses excite oxygen and nitrogen molecules in the air, creating the lights that are normally visible only near the planet's poles and in high-latitude locations like Alaska.

It is easy to see sunspots from home with proper, safe viewing techniques. Astronomers suggest projecting the Sun's image through binoculars onto a white surface, like paper. Never look directly at the Sun, however, not with the naked eye or through binoculars or telescopes; serious eye damage will result.

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