Pilot Brian Whittaker has spent thousands of hours flying back and forth to London from the USA, and he has seen countless wonders of the night sky through the glass of the cockpit. This week for the first time, he photographed a sprite
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"I was very excited to finally photograph a sprite on the American Plains!" says Whittaker. "On June 16th, I was flying from Las Vegas to London when we flew by several very active thunderclouds. I had a prolonged view of countless rapid lightning flashes. This sprite leaped up from one of the thunderclouds."
The green bands in Whittaker's image are not auroras, but rather airglow. Airglow is caused by an assortment of chemical reactions in Earth's upper atmosphere. These reactions get started during daylight hours when the atmosphere is bathed in strong UV radiation from the sun. Sometimes, on dark nights, the green afterglow is visible, colored green by oxygen atoms 90-100 km high. Airglow occurs just above the altitude of most sprites.
"Sprites are really high up!" says Whittaker. "I wonder how many earlier sprites I've missed over the years because my camera was set just a little too low?"
Indeed. Summer is the season for sprites, and a good time for photographers to point their optics high, over the tops of towering thunderheads. Here's how.
