The aurora may be seen at certain parts of the earth at a maximum of 200 to 250 nights of the year (depending on the sunspot cycle). These parts of the earth are defined in geographical terms as the Auroral Zone. This zone is located in a circular region around the magnetic north and south poles between 65 and 75 degrees latitude. However, the Aurora is actually distributed about an oval-shaped band that rotates about the auroral zone. This band is called the Auroral Oval.
The aurora in the northern Auroral Oval is called the Aurora Borealis while the aurora in the southern Auroral Oval is called the Aurora Australis. The auroras in both the northern and southern ovals are a mirror image of each other, and therefore move in similar ways.
Sections of the aurora can be seen on the earth at different times of the day. As the day progresses, the Aurora recedes from the horizon in a northern direction.
When the auroral activity is weak, the Auroral Oval "shrinks" to about 65 to 70 degrees lattitude. Opposingly, when the auroral activity is stronger, the Auroral Oval can expand to nearly 60 degrees latitude (making the viewing range much greater).