Many Central Illinois residents were treated to a rare sight in the sky this week — the Northern Lights, also known as the Aurora Borealis. The colorful display of greens, purples, and pinks could be seen across much of the Midwest, and conditions tonight could bring another chance to spot them.

So what causes this natural light show? The Northern Lights happen when particles from the sun collide with gases in Earth’s atmosphere. Those particles, carried here by solar winds, hit oxygen and nitrogen high above the Earth, creating glowing colors that ripple and dance across the sky.

Scientists say increased solar activity,  known as a geomagnetic storm, is what’s making the lights visible much farther south than usual. Normally, the aurora is only seen in places like Canada or Alaska.

There are plenty of apps available that you can download to tell you when to see the Northern Lights and you can also visit https://www.spaceweatherlive.com/  The best viewing is usually away from city lights, facing north, and between 10 p.m. and 2 a.m.