Lightning is a beautiful but dangerous beast: While we’re pretty good at observing it from the ground — and occasionally, being struck by it — there’s still some mystery about how the electrical discharges in the upper layers of our atmosphere actually work. The names given to these discharges (such as red sprites, pixies, elves) sound like the musings of a Dungeons & Dragons zealot rather than legitimate scientific phenomena. But at long last, scientists have been able to study images and video of one these elusive happenings — called blue jets — and the results are as spellbinding as lightning itself.
View of blue jets, taken from the ISS. (Image: ESA)
On a 10-day trip aboard the International Space Station (ISS) back in September 2015, Denmark’s first astronaut — Andreas Morgensen — helmed a project around studying lightning, aptly named Thor. He was able to capture images of some of the rarest electrical storm phenomena, including this video of a massive storm above India, where elusive blue jets can be seen. Blue jets are columns of electrical discharge that fan out above cloud tops and disappear after a few tenths of a second, and yeah — we have no idea why they’re blue.
While the video has been circulating for about two years, recently, a team of scientists published their research on these blue jets in the Geophysical Research Letters. Some scientists have been sceptical to accept blue jets as legitimate occurrences, since they hang out above clouds, making them difficult to observe. But according to these researchers, Morgensen’s work gives us the first ever glimpse at a pulsating blue jet reaching 40km.
“We have ruled out the possibility that the discharges are scattered light from lightning flashes inside the cloud since all of these are observed to have a relatively weak blue component,” the team wrote. “The observation of blue surface discharges with these characteristics is, to our knowledge, the first of its kind.”
The research shows that these images are a good starting point for understanding how blue jets and other disturbances in the stratosphere could affect Earth’s radiation balance. Later this year, NASA will send an observation facility called Atmosphere-Space Interactions Monitor (ASIM) to the ISS in order to study upper atmospheric storms and their impact on Earth’s climate. While it’s not as catchy — or cool — as “Thor”, ASIM will provide scientists with much-needed information on these bad and beautiful phenomena. Still a win in my book.