Nature offers many dazzling displays, from jagged flashes of lightning to radiant sunsets. But perhaps one of the most elusive natural phenomena is the shimmering waves of green, pink, and red dancing across the night sky, forming the northern lights.

These glowing displays – known as the aurora borealis in the northern hemisphere and the aurora australis in the south – are caused when charged particles from the sun flow toward Earth and get caught in our magnetic field.

The particles follow magnetic field lines toward the polar regions, where they collide with gases in the upper atmosphere. These collisions cause the gases to glow, similar to how electricity lights up a neon sign.

The sun constantly releases a stream of particles called the solar wind. When the sun "erupts" – either through a coronal mass ejection or from coronal holes – billions of tons of plasma race toward the Earth at millions of miles per hour.

As this solar energy slams into Earth's magnetic field, it creates geomagnetic storms. These storms push the northern lights, which are often found near the poles, southward and intensify the colors. During strong solar storms, people across the U.S. can view the northern lights – as far south as the Gulf Coast.

While photos of the northern lights typically show green streaks in the atmosphere, other colors can occur as well. Purple and blue streaks can be caused by nitrogen molecules close to Earth's surface, green colors light up from oxygen molecules 100-250 miles above the Earth, and reds occur higher yet as oxygen molecules more than 180 miles from Earth glow. Sometimes the faint colors can appear white to the naked eye, but long-exposure photography that lets in more light than our eyes can see will reveal the true colors.

The northern lights can take many forms: smooth arcs stretching from horizon to horizon, rippling curtains, or dancing waves across the sky. 

The National Oceanic and Atmospheric Administration (NOAA) has a Space Weather division that issues aurora forecasts several times each day. Scientists make forecasts days – or even weeks – ahead by spotting solar flares, coronal ejections, and coronal holes on the Sun's surface. Satellites positioned between the Earth and the Sun can provide more specific forecasts just 45 minutes in advance by measuring the precise solar wind.

The northern lights are most common during and just after the Sun's 11-year solar maximum, which is occurring in the 1-3 year period centered on the year 2025. During these periods of enhanced solar activity, there are more sunspots, solar flares, and coronal mass ejections, which increase the chances for geomagnetic storms and auroras. NOAA and NASA expect this heightened activity to continue into 2026 before eventually declining.