More than your typical celebratory fireworks will fill the sky this holiday weekend in the United States.
For the past week, sky-watchers have been reporting and capturing on camera mysterious reddish-orange flashes of light high in the night skies, dubbed “sprites.”
Considered a myth until an airline pilot captured their flickering lights above a thunderstorm on film in 1989, these momentary bursts of electricity can literally reach the edge of space, about 50 miles (81 kilometers) above the ground.
They have remained so elusive because normally clouds obscure sight of them. Sprites are related to lightning. This rare, bizarre phenomena is produced when discharged electricity shoots out from the top of a cloud, instead of heading to the ground as lightning.
You have the best chances of seeing sprites throughout the Midwest from Colorado to Minnesota, and as far south as Texas. Around the world, sprites have been seen in storms above South America, Africa, and Australia.
Here are some observing tips: To see them with the naked eye during a storm, find a sheltered location far away from the blinding lights of the city. Haze and air pollution can also block sprites from view.
Gaze well above the top of a thundercloud while blocking out all the lightning action below with a piece of cardboard. Expect them to occur every ten minutes or so on average at the height of the storm.
Double appearance of sprites during a thunderstorm. Courtesy of Thomas Ashcraft, www.heliotown.com
How to capture these luminous electrical bursts on camera?
Thomas Ashcraft has been fortunate enough to grab some eerily beautiful portraits of sprites in action, and he has come up with a recipe for success:
As a first step, check the Internet weather services for strong thunderstorms within 500 miles (805 kilometers) of your location using regional radar maps, he recommends.
“I aim my cameras out over the direction of the thunderstorms—which will be hot red or purple on the radar maps—and shoot continuous DSLR exposures,” he said.
“I usually shoot continuous two-second exposures, but if there is no moon then I will shoot up to four-second exposures. It might take hundreds to usually thousands of exposures [to capture one sprite], so be prepared for many shutter clicks.”