Red sprites and blue jets

ESA astronaut Andreas Mogensen explains the phenomena he filmed over India from the International Space Station’s Cupola observatory in September 2015 during his postflight tour at ESA’s technical heart ESTEC in The Netherlands.

The film shows lightning illuminating clouds and recently discovered phenomena called blue jets and Red Sprites.

As part of his 10-day mission Andreas performed an experiment called Thor after the god of thunder, lightning and storms in Nordic mythology. Initiated by the Technical University of Denmark, Thor had Andreas test a new thundercloud imaging system that looks at the electrification of lighting.

Researchers are particularly interested in newly-discovered lights that occur in the upper atmosphere during thunderstorms called red sprites, blue jets and elves. Sprites last 20 milliseconds at most, and to capture them on camera is a real challenge. They received their name because of their elusive nature. Blue jets are found up to 50 km altitude with Red Sprites occurring between 60-80 km altitude.

Andreas received the coordinates of a few possible thunderstorms together with the times and instructions on which lens, filter and camera settings to use.

Some of the most violent electric discharges are very difficult to capture from the ground because the atmosphere blocks radiation. Apart from covering all the main thunderstorm regions, the International Space Station brings scientists as close as possible to the electric phenomena. Its great vantage point has the lowest orbit available for observation at around 400 km altitude – imaging satellites mostly operate at 800 km.

Read more about Andreas’s iriss mission: www.esa.int/iriss