DES MOINES, Iowa — If you see a thunderstorm in the distance at night, keep your eye on the sky above the cloud and you might see a surprising pop of red.
These red flashes are known as lightning sprites, and chances are you've never even heard of them before.
A sprite is a faint, red electrical discharge that occurs high above a thunderstorm. They are incredibly large, stretching from the top of a thunderstorm to upwards of 60 miles above the Earth's surface.
That is six times higher than the strongest thunderstorms on Earth.
There are a lot of unknowns about lightning sprites, but they are thought to be triggered by cloud-to-ground lightning strikes and act to balance electrical charges in the atmosphere.
Sprite clusters can be very wide, some covering more than 30 miles. Picture a huge flash of red light stretching from Ames to Ankeny.
They take on various shapes, resembling everything from jellyfish to carrots to columns.
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Sprites are a relatively new discovery by scientists. Several pilots in the 20th century reported these red flashes above thunderstorms.
However, they weren't captured on film until 1989.
Nowadays, improved technology has allowed photographers to routinely capture them on camera. Since they flash for less than a tenth of a second, sprites are difficult to see with the naked eye.
You'll need an unobstructed view of a distant thunderstorm away from light pollution.
If you adjust your eyes long enough, perhaps you will be one of the lucky few to get a glimpse of these elusive flashes.