In the time it has taken me to write this, lightning has struck the earth over 500 times. It is one of the most spectacular, mesmerizing, and awe-inspiring natural phenomena. For all of its beauty and power, it still holds many mysteries.
As recently as the 1990s, we had only anecdotal evidence of the majority of lightning’s many incarnations. At that time, thanks to videotape evidence from NASA’s Space Shuttle missions, actual observations of sprites, jets, and later ELVES (Emissions of Light and Very Low-Frequency Perturbations From Electromagnetic Pulse Sources) would all be confirmed and studied.
Jets, later known as ‘Blue Jets’ have proved to be a difficult phenomenon to observe from the earth given that cloud cover is a necessary ingredient for their appearance. Blue Jets had been thought of as an exotic and rare occurrence. Classical lightning is the discharge caused by the massive charge imbalance between huge negative charges within storm clouds and intense positive charges on the ground or ocean. The energy release and timescales involved are mindboggling. The air surrounding a person struck by lightning can heat up to 50,000ºF (27,700ºC), ten times the surface temperature of the sun. What we observe as the flash is really the plasma created by the energy as it ionizes the atmosphere.
Blue Jets are initiated by the positively charged tops of cumulus clouds as they encounter a region of negative charge at the cloud boundary and layer of air above. They propagate upwards, as a leader is created along this ionized channel of air. At least this is the currently accepted theory.
Thanks to research led by physicist Torsten Neubert from the Technical University of Denmark published in Nature, we are gaining a clearer picture of the complex phenomena we know as lightning. Using data collected from the Atmosphere-Space Interactions Monitor (ASIM) observatory in 2019 where five Blue Jets were observed they have pieced together a credible sequence of events which points to the fact that the jets and elves are a consequence of regularly occurring conditions within storm clouds. They simply occur over brief timeframes.
The ASIM data confirms that lightning discharges gave rise to expanding rings of optical and ultraviolet electromagnetic pulses in the lower ionosphere – elves. They are establishing a chain of causality among the events occurring.
The researchers liken the Blue Jets and red sprites to the well-documented high-power radio-frequency events known as narrow bipolar events which trigger lightning within storm clouds. They are not really rare and exotic. We simply haven’t had the opportunity to observe them with any regularity in the past.
Do you want to publish on Apple News, Google News, and more? Join our writing community, improve your writing skills, and be read by hundreds of thousands around the world!