On Thursday morning, you may be talking about what you watched on Wednesday night. But we're not talking about a TV show. Many parts of the U.S. could be treated to a rare but spectacular celestial event: The northern lights, the aurora borealis, may be on display. National Oceanographic and Atmospheric Administration (NOAA) forecasters estimate that there is a 45% chance of such "geomagnetic activity," according to SpaceWeather.com.
Why now? On Monday, the sun let loose its biggest solar flare in four years. NASA explains that a solar flare "occurs when magnetic energy that has built up in the solar atmosphere is suddenly released. Radiation is emitted across virtually the entire electromagnetic spectrum." NASA says that the "amount of energy released is the equivalent of millions of 100-megaton hydrogen bombs exploding at the same time."

It takes about a day or so for radiation from this flare to reach Earth's atmosphere, according to Space.com. And as the website How Stuff Works explains, the aurora borealis occurs when "when highly charged electrons from the solar wind interact with elements in the earth's atmosphere."
Web searches on "solar flare 2011" and "solar flare photos" have shot up at the speed of light. In just 24 hours, online lookups jumped 1,038% for solar flares. Folks in the northwest were particularly intrigued: Oregon, Washington, and Idaho provided some of the biggest buzz. And with good reason: States up north may have the best chance of viewing the flare's effect on Earth's atmosphere.
Read More: Yahoo