MINNEAPOLIS - If you have seen the northern lights before you may have seen a spectacular view across the sky, but have you ever seen a purple ribbon of light?
It's a type of northern light that has been unknown until a recent effort with citizen scientists and satellite observations helped us understand how it forms.
That purple light is called STEVE, an acronym short for Strong Thermal Emission Velocity Enhancement.
The purple ribbon forms from a concentrated flow of charged particles in Earth's upper atmosphere. It's similar to how the green ribbons form, except STEVE forms south of where a typical green aurora develops.
The next time we have a chance to see the northern lights, look for STEVE in the sky.