© Reuters/ISSThis aurora australis image was taken during a geomagnetic storm that was most likely caused by a coronal mass ejection from the Sun on May 29. The photo was taken from The International Space Station. Increased solar activity over the next two years will push these displays farther from the poles, making them visible to people as far south as the continental US and as far north as Buenos Aires.
Increased solar activity could give residents of the continental U.S., southern Europe and Japan the chance to see the northern lights for the first time in several years.
The National Weather Service's Space Weather Prediction Center says the sun is entering a period of high activity, marked by more sunspots and a greater chance of a coronal mass ejection, or CME, hitting the Earth. That would result in auroras being visible much further from the poles than they usually are.
A CME is essentially a blast of charged particles (mostly protons and electrons) that speeds outward. Most of them pass by and humans never notice, but occasionally the Earth is in the way. When that happens, the particles - enough to weigh as much as a small asteroid -- hit the Earth's magnetic field and get trapped.
They then are pushed at high speeds to the polar regions, where they hit the atoms of oxygen and nitrogen in the atmosphere and ionize them. The atoms release energy as light and form the
aurora borealis, or northern lights. (The same thing happens in the southern hemisphere, where it is called the
aurora australis). That is why the closer to the poles you are, the better chance you have of seeing the auroras.