LSO
Lightning and Sprite Observations.
What is the aim of the experiment?
Sprites are a meteorological phenomenon discovered in 1989, which have the appearance of a luminous glow above lightning storms between 50 - 90km above the Earths surface. Sprites have a duration of only a few milliseconds and are caused by powerful lightning strikes, which affect the electrical field in the ionosphere (part of the upper atmosphere). The aim of this experiment is to observe sprites during storms, determine the energy emitted by them (and elves, which are similar phenomenon to sprites), and compare this to nightly emissions of lightning. It is also planned to compile statistical data to determine the frequency of sprites and their origin.
Why do it in space?
The altitude at which sprites have been observed, and the fact that they occur above cloud tops extending in an upward direction, make it impossible to view them from the ground. Low-earth orbit is an optimal vantage point for studying this phenomenon. This is also how they were originally discovered.
What is it good for?
Since sprites are associated with thunderstorms and lightning, scientists suspect the flashes may be a form of electrical discharge. If so, they could present a concern to high-altitude research aircraft, which means that a more in-depth understanding of this phenomenon is required. Lightning, on the other hand, is something we have always lived with, and yet its mechanisms are still not totally clear. This ever-fascinating phenomenon of nature often plays havoc with radio communications and power lines and it is important to be able to predict when and where they will strike to take necessary precautions and countermeasures.
Team Members:
E. Blanc
Commissariat à l'Energie Atomique (CEA)
BP 12
F-91680 Bruyeres le Chatel
France
P.F.J. van Velthoven
KNMI (Royal Netherlands Meteorological Inst.)
De Bilt,
The Netherlands
More Information:
A Fact Sheet of the LSO experiment is available for download as pdf-file in English and in Dutch.
A summary description of the LSO experiment in Dutch is available at the ESA Dutch Internet Portal.