Lightning "dances" on edge of space: Sprites

William Atkins
Monday, 08 June 2009 18:29

Science - Space

And, Lyons and Schmidt add, “On the tape appeared a mere two frames of video showing bright columns of light towering high above distant thunderheads over northern Minnesota. This was the first documented proof of what was at first called “cloud-to-space lightning,” but has since become known as the red sprite. The sprite sightings were soon followed by blue jets, elves, trolls, gnomes and pixies...fanciful names all chosen to avoid implying that we knew more about the physics of the phenomena than was warranted.”

NASA’s astronauts verified the existence of sprites from 1989 to 1991. The article The role of the space shuttle videotapes in the discovery of sprites, jets and elves, states, “The phenomenon, now known as a sprite, was first accidently documented on ground based videotape recordings on the night of 6 July, 1989. Video observations from the space shuttle acquired from 1989-1991 provided 17 additional examples to confirm the existence of the sprite phenomenon."

On June 5, 2009, Spanish atmospheric scientist Oscar van der Velde (Sant Vicenc de Castellet, Spain) photographed one of these sprites.

Its image appears on the SpaceWeather.com Web site: http://spaceweather.com/.

And, an enlarged version is found at: Oscar-van-der-Velde1.

Van der Velde states, “With my new zoom lens I can now magnify the sky above thunderstorms to get very detailed images of sprites. This amazing 'carrot sprite' occurred near the coast of southern France about 250 km away from me."

He adds, "Sprites are a true space weather phenomenon. They develop in mid-air around 80 km altitude, growing in both directions, first down, then up. This happens when a fierce lightning bolt draws lots of charge from a cloud near Earth's surface. Electric fields [shoot] to the top of Earth's atmosphere--and the result is a sprite. The entire process takes about 20 milliseconds."

And, "I [van der Velde] set up a Watec 902H2 Ultimate security camera on my balcony and used UFOCapture software to catch the sprite.”

Groups of people called Sprite Chasers hunt for these upper atmospheric electric phenomena. Check out EuroSprite 2009.