#morgensen

Blue Jets

Scientists at Denmark’s National Space Institute were studying blue jets, an elusive phenomenon similar to lightning, but there was a lack of visuals to aid in their research. So, in 2015, European Space Agency Astronaut Andreas Mogensen, the first Dane to fly in space, was recruited to the wonderfully named experiment “Thor”. His mission to the International Spaces Station (ISS) lasted just 10 days, but in that time, he managed to record video of blue jets for the first time from space during a thunderstorm over India.

Blue jets, much like sprites (http://bit.ly/2kA4Sdu) are difficult to study. They’re a rapid discharge of electrical energy caused by the static charges that build up during thunderstorms, last only a fraction of a second, and can only be photographed from above the clouds. Blue jets are different from lightning in that the discharge is more focused, meaning nitrogen in the surrounding air is impacted by a bigger charge, resulting in a blue glow.

Pilots have talked discreetly amongst themselves about blue jets for decades, but were reluctant to admit they had seen them for fear of losing their license. Then, in 1989, scientists inadvertently recorded blue jets on video. Since then, blue jets, along with other transient luminous events (TLE) (basically, electrical-discharge phenomenon at altitudes above those of normal lightning), have been studied but with great difficulty given how challenging it is to even see them.

In order to get the best possible visual of blue jets, Thor was carried out from September 2 through 11 of 2015. Teams on the ground forecasted thunderstorm activity along the orbit of the ISS and provided optimal camera angles for recording any TLE, then uploaded that information to the ISS every 24 hours. Morgensen filmed the storms at 24 frames per second (among other carefully selected camera settings) and everyone waited and hoped that he’d be filming in the right place at the right time to catch a blue jet. He was. The blue jets Morgensen recorded were kilometers high; possibly 20 kilometers or more.

While Thor was a success, there’s still much to learn. Fortunately, more research into lightning and TLE from the ISS are planned.

RE