[O-03] Poster presentations by senior high school students

[O03-P60] The change with time of the gigantic jet off the coast of Ibaraki on December 11, 2017 and comparison with the past jets

*Naoya Yamashita¹, *Shin Hirano¹, *Hayato Matsuyama¹, *Yuya Okubo¹ (1.Shizuoka Prefectural Iwata Minami High School)

Keywords:gigantic jet, troposphere

Our school and Aoyama Gakuin University observed a kind of gigantic jet of transient luminous events on December 11, 2017. The occurrence point is identified with Ibaraki prefecture off the coast by way of the triangulation from 2 points, and the upper altitude is 66.3km Also, we examined the gigantic jet by dividing it into five parts based on the characteristics of light emission. As a result, it becomes clear that the upper part emits light first, and after the light emission weakens, that of the lower part become stronger. Furthermore, it was considered that the gigantic jet was triggered by a discharge in the cloud due to the accumulation of a large amount of electrical charge in the troposphere, in comparison with the weather observation record and the previous research. In addition to them, we compared this jet with the three past gigantic jets and found out common and different points. As common points, all four jets occurred from late November to mid-December, and they almost didn’t have rain. But their shape, altitude and light emission time are very different.