Fairbanks, AK - A graduate student from the University of Alaska, Fairbanks has garnered national media attention after he posted photos of a rare lightning-related phenomenon to his blog.
Thunderstorms can produce dark grey clouds and blazing flashes of white lightning, but above all that, things are much more colorful. University of Alaska Fairbanks, PhD student Jason Ahrns says pilots have reported bright red flashes of light above thunderstorms for decades. “Some people kind of dismissed those as people seeing things," he says, "because nobody had any real evidence.”
Ahrns is part of team of researchers who spent the summer flying over Oklahoma, Kansas and the Midwest aboard a National Center for Atmospheric Research aircraft. They’re photographing sprites. “They’re just this weird alien jellyfish looking shape,” says Ahrns. But sprites are actually the result of positively charged lightning. They usually appear bright red in photos, but they show off hints of blue light. “It’s basically a glow," he says, "just like a fluorescent light bulb. Where there’s a big electric potential in the atmosphere and it just makes the atoms up there glow.” But spotting a sprite is the ultimate challenge. They occur almost too quickly for the human eye to detect. “They’re very fast and they’re over in a few milliseconds," explains Ahrns. "So, if you blink at the wrong time, it’s gone, but they’re really large. It really impressed me how large they are. We were flying like a hundred miles away from it and it’s still large enough to go from the top and bottom of my vision all the way.”
Normal cameras aren’t fast enough to capture a sprite as it develops. “So we use these high speed cameras so that we can watch the sprite develop over time, slow it down a lot and then we can actually see what’s going on. The idea there is to see how these little streams coming off of it, how they propagate through the atmosphere, what they’re made of, what kind of atmosphere they’re exciting to cause this light and we can determine what causes sprites and what effect they might have on the rest of the atmosphere.”
Ahrns posted photos and video of sprites he captured this summer to his blog. What happened next was unexpected. He started getting calls and emails from the Washington Post, the Atlantic Cities Project and NPR’s breaking news blog, The Two-Way. “I kind of figured it would make the rounds on science news sites," he says, "but I didn’t expect it to go mainstream and I didn’t expect this many people to be interested. I guess it just shows how much the general public is interested, if you can just get it out there to ‘em.”
The research team took more than 11 thousand photos during a single flight just this week. They’ll be evaluated along with thousands of others as part of a joint research effort between UAF, the US Air Force and the National Science Foundation.