Some lightning never comes down
Above large thunderstorms the upper atmosphere flashes upward: red sprites, blue jets, and elves, kilometres above the cloud tops.
Established2 min read
A sprite is a red, branching flash in the mesosphere, tens of kilometres above the anvil, triggered by a powerful positive lightning stroke to the ground. Blue jets shoot up from the cloud itself. Elves are expanding rings of light at the edge of space, a pulse of electromagnetic energy heating the air.
The first accidental video of a sprite was published in 1990. Since then they have been photographed from the ground, from aircraft, and from the International Space Station. They are ordinary plasma physics in thin air. They are not the bolt that hits a tree.
Caveats
- They are faint and brief, and usually invisible from the ground under the storm that causes them. You look from the side, far away, at night.
- Names like 'sprite' are nicknames. The events are catalogued and reproduced in models.
Sources
- 1Franz R. C., Nemzek R. J., Winckler J. R.. Television image of a large upward electrical discharge above a thunderstorm system. Science 249, 1990.