He watched the video of an enormous jellyfish sprite - named for its resemblance to the sea creature - extending its tentacles from miles up to graze the tops of the clouds. Filmmaker Hank Schyma had the perfect conditions to capture footage of sprites - plumes of purple, pink, and red light dancing above thunderstorms.īut as he reviewed his footage, Schyma saw something completely unexpected. About 50 miles to the east, lightning darted from looming dark clouds. Lightning: Transient luminous events (TLEs), International Cloud Atlas, World Meteorological Organization website.It was a clear, starlit night on the border of Texas and Oklahoma.Article describes investigation of an incident involving a scientific baloon on 5 June 1989. "Full report on the uncontrolled free fall of a stratospheric balloon payload provoked by a Sprite" STRATOCAT website."Once Upon a Time in a Thunderstorm" an article from the NASA website concerning observations of TLEs from the International Space Station, 10 April 2018.It is possible that sprites and jets could cause electromagnetic pulses in the flight electronics of aircraft flying directly overhead a storm but evidence is limited (see Further Reading). They are so quick (0.001 seconds), that it is impossible to see them with the naked eye. The light is generated by the excitation of nitrogen molecules due to electron collisions (the electrons possibly having been energized by the electromagnetic pulse caused by a discharge from an underlying thunderstorm). They occur in the ionosphere 100 km above the ground over thunderstorms. ElvesĮLVES (Emission of Light and Very Low Frequency perturbations due to Electromagnetic Pulse Sources) are indistinct types of TLE, producing large diffuse and expanding ring-shaped glows, up to 400 km in diameter. Gigantic jets, which are relatively rare, reach higher altitudes than blue jets (up to 70 km), and the upper portion of the jet changes colour from blue to red. In a similar process to how blue jets form, the higher charge region is discharged by the leader network before the same occurs in the lower charge region, and one end of the leader network propagates upward from the cloud toward the ionosphere. Where blue jets are believed to initiate between the upper positive charge region and a negative screening layer directly above this region, Gigantic jets appear to initiate between the upper positive and lower negative charge regions in the thundercloud. The colour is believed to be due to a set of blue and near-ultraviolet emission lines from neutral and ionized molecular nitrogen. The positive end of the leader network fills the negative charge region before the negative end fills the positive charge region, and the positive leader subsequently exits the cloud and propagates upward. Source: Wikicommons.īlue jets are believed to be initiated as "normal" lightning discharges between the upper positive charge region in a thundercloud and a negative "screening layer" present above this charge region. Author: Gemini Observatory / Association of Universities for Research in Astronomy (AURA). Based on their shape and visual appearance, we distinguish three types of sprites: jellyfish, column and carrot sprites.īlue Jet as seen from summit of Maunakea, Hawaii, 24 July 2017. Unlike tropospheric lightning, sprites are cold plasma, similar to fluorescent tube discharge. They are reddish-orange or greenish-blue in colour with hanging tendrils (sometimes referred to as "carrot sprites") and arcing branches above. Sprite is also an acronym for Stratospheric/mesospheric Perturbations Resulting from Intense Thunderstorm Electrification. Sprites are short-lived flashes of bright red light that occur above large storm systems, reach 50 – 90 km in altitude, and are triggered by positive discharges of lightning between the top of a thundercloud and the ground (commonly called positive giants). Although there had been reports of such phenomena by pilots and others for some years, it wasn’t until 1989 that TLEs were documented photographically with full scientific investigations to follow. Sometimes called upper atmospheric lightning or ionospheric lightning, transient luminous events (TLEs) are short-lived electrical-breakdown phenomena/electrically induced forms of luminous plasma that occur well above the altitudes of normal lightning and Cumulonimbus (Cb) clouds.
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