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ストラトスフィアの青いジェットの発生の観測
Torsten Neubert1, Olivier Chanrion2, Matthias Heumesser2
1National Space Institute, Technical University of Denmark (DTU Space), Kongens Lyngby, Denmark. neubert@space.dtu.dk.
Nature
|January 21, 2021
まとめ
青いジェットは雷雲から発生する 大気中の電気放電です 新しい研究によると これらの閃光は 層次圏に到達し 大気中の電気やエルフのような現象の 洞察力を提供しています
科学分野:
- 大気中の電気
- 航空宇宙物理学
- プラズマ物理学
背景:
- 青いジェットとは 雷雲から平流圏に広がる 短時間の円形の大気中の電気放電です
- 形成には電気的崩壊とリーダー-ストリーマー移行が伴うが,リーダーの性質と高さはよくわかっていない.
- 以前の研究では 雲の上の閃きと 狭い双極現象が関連付けられていて 短いラジオパルスと 強い放射線が特徴でした
研究 の 目的:
- 青いジェット発射の性質と高度を記述する.
- マイクロ秒の閃きと 青いジェットと イオン圏の相関を調べる
- 大気中の放出におけるリーダー要素からの光学的な放出を理解する.
主な方法:
- 国際宇宙ステーションから10マイクロ秒の時間解像度のスペクトル測定が行われました.
- 観測は雷の電池に集中し 放電の無邪気な視点を提供しました
- データ分析は,光学放出と同時発生のイオン圏現象を相関させた.
主要な成果:
- 雷の嵐で発生した 微秒間の青い閃きが5回観測されました
- 一瞬の閃きで プラトパウズまで広がる 脈動する青いジェットが起きました
- 閃光はイオノスフィアの"エルフ"に伴い 光学的な放射は ストリーマーイオン化波を示唆しています
結論:
- 観測されたマイクロ秒の閃光は 負の狭い双極性イベントの光学的なサインである可能性が高い.
- これらの出来事は,雲から地への稲妻と,平流圏への青いジェットの両方を開始することができます.
- この発見は上層大気圏の 電気現象の理解を深めています
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