Groups such as Nagoya University, Information and Communication Research Organization (NICT), Kyoto University, Aeronautical Research and Development Organization (JAXA), University of Electro-Communications, Tohoku University, and National Institute of Polar Research have joined the "Killer Electronics" along with the aurora called pulsating aurora. Proposed a new theory that "descends from space into the atmosphere."This theory was proved by simulation and showed to be consistent with the observation results of JAXA's "Reimei" satellite and NASA's "SAMPEX" satellite.

 The pulsating aurora is characterized by the fact that faint light of various sizes repeats blinking in various cycles, and is thought to be caused by a special radio wave (chorus) in outer space called "the song of the universe."On the other hand, killer electrons are high-energy electrons that fall from outer space in large quantities in a short time of less than one second due to a phenomenon called microburst, and are often called killer electrons because they often cause the failure of artificial satellites. There is.

 In this study, as a result of calculating the interaction between chorus and electron by computer simulation, we found that pulsating aurora and microburst are actually a series of phenomena.The theory is that a chorus is first generated, relatively low-energy electrons are scattered into the atmosphere, causing a pulsating aurora, and then the chorus propagates to high latitudes and directs higher-energy electrons (killer electrons) toward the atmosphere. It was explained that it scatters (microburst).It is said that this theory could explain the phenomenon actually observed by the satellite, and its validity was proved.

 Killer electrons are thought to destroy ozone in the mesosphere near an altitude of 60 km.In other words, this theory suggests that when the aurora is blinking, killer electrons are likely to fall into the atmosphere and ozone is destroyed.

 Aiming to prove this theory, sounding rocket experiments by NASA, JAXA, Nagoya University, etc. are scheduled to be conducted in Alaska, USA in 2021.

Paper information:[Geophysical Research Letters] Relativistic Electron Microbursts as High Energy Tail of Pulsating Aurora Electrons

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