In our atmosphere, when a high-energy electron bumps into an atom of oxygen, the oxygen becomes excited. If the oxygen atom can hold onto that energy for a fraction of a second, it will give off green or red light. Overlapping reds and greens can produce a yellowish glow. When millions of atoms sparkle together, the sky erupts with a brilliant aurora. The billowy curtains seen by viewers result when the electron beams from the magnetosphere ripple and swirl through air molecules like paint brushes in the sky.
Times are better than ever for catching an aurora.
With satellites monitoring solar activity around the clock, scientists are getting better at predicting auroras. These predictions are posted on the internet, giving this generation of aurora enthusiasts an even better chance of seeing a good show. Unfortunately, the predictions aren t always accurate. Vondrak likens aurora forecasting to predicting tornadoes. Likewise, scientists can detect storm activity on the sun, but knowing whether, when and how they may interact with Earth s magnetic field is another story.