Observations of transient luminous events from earth orbit

We review the results of space-based observations of Transient Luminous Events occurring in the upper atmosphere in conjunction with intense lightning flashes. The global rate of these events has significant implications on the global electrical circuit, combining the lower troposphere with the ionosphere. The needed TLE climatology can be best addressed by orbiting space platforms. The results from various such platforms are presented: from early Space Shuttle missions, the MEIDEX campaign, the LSO on-board the ISS and unmanned instruments on the FORMOSAT-2 and RHESSI satellites. Future missions are briefly described.