ScienceDaily (Aug. 14, 2012) — High above the clouds during thunderstorms, some 50 miles above Earth a different kind of lightning dances. Bursts of red and blue light, known as "sprites," flash for a scant one thousandth of a second. They are often only visible to those in flight above a storm, and happen so quickly you might not even see it unless you chance to be looking directly at it. One hard-to-reach place that gets a good view of sprites is the International Space Station. On April 30, 2012, astronauts on the ISS captured the signature red flash of a sprite, offering the world and researchers a rare opportunity to observe one.
http://www.sciencedaily.com/releases/2012/08/120814144839.htm