Sprites, blue jets and ELVES are lightning-triggered optical emissions which occur in the rarefied atmosphere above thunderstorms. Images of these phenomena first appeared in the scientific literature less than a decade ago and the mechanisms responsible for their generation are not yet fully understood. One of the factors hindering a fuller understanding is the scarcity of good quality video observations around the world. Several features of the ISS make it an ideal platform from which to study such events. This paper proposes an experiment consisting of an astronaut tended, ground controlled, low light level video camera, sensitive to both visible and infrared light, mounted on an Earth-facing payload site aboard the ISS. Ideal observation windows would be selected beforehand to make optimal use of the data down-link bandwidth and astronaut time. This would involve using existing ground-and space-based meteorological observation networks to identify mesoscale convective systems (i.e. energetic thunderstorms), above which sprite phenomena typically occur. Astronaut observations from the cupola would facilitate the identification of regions of high activity; these are not always clear on wide-field video images. Real-time decisions made by the astronauts on where to point the camera would enable the operators to zoom in on an area of interest, and record events with high spatial and temporal resolution. Sub-millisecond timing of video frames, required for correlation with complementary ground-based observations such as very low frequency radio recordings and lightning detection data, could be supplied by the ACES clock on ISS. Coordinated ground-based, airborne and coarse satellite observations could be used for triangulation, and hence accurate position and size determination. Finally, the program could exploit the ISs's long lifetime by studying the effects of the solar cycle on the occurrence of sprite phenomena.
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