CAM Sprite

The primary objective of this project is to train students in the problems associated with the observation of Transient Luminous Events (TLEs), specifically in optical and electronic devices, triggering algorithms, image processing, and TLE physics.

For this purpose, we have installed a CCD camera on the roof of the LPC2E. The TLEs that can be observed from Orleans are the “sprites”. They result from the electrostatic coupling between the charge deposited by a lightning in a storm and the lower layers of the ionosphere. Sprites are large discharges (50 km vertical) made of multiple plasma filaments and are very brief (a few milliseconds). They were first observed in the 90’s and were then considered as rare events. Today we know that these events are in fact frequent and even observable from Orleans (which is located in a region with few storms).

CAM Sprite on the roof of LPC2E.

The following figure shows a set of sprites whose parent lightning bolt was located off Île de Ré, i.e. 375 km from LPC2E on September 13, 2016 à 20:06:15 UTC.

Sprite highlighted by the Watec 902-H2 camera (Tamron 4-12 mm F1.2 AS IR lens, IOTA VTI GPS inlay) installed on the LPC2E roof. Credit S. Célestin.