Orbiting above a storm recently, International Space Station astronauts captured a rarely seen type of sky show on camera: a fleeting electrical burst called a red sprite. And not just any sprite.
The red sprite’s exceptional size (in a word, giant), plus the resolution and sense of scale in the picture—distributed by NASA this week—have experts intrigued, despite the fact that red sprites have been seen from space before.
Red sprites are electrical bursts that occur above highly active thunderstorms. They’re rarely observed from the ground or space, due to their high altitudes (about 50 miles/80 kilometers above Earth), milliseconds-long durations, and relative dimness, compared with lightning.