金星では,地上の雷の特徴である高周波無線信号が検出されなかった
D A Gurnett1, P Zarka, R Manning
1Department of Physics and Astronomy, The University of Iowa, Iowa City 52242, USA. donald-gurnett@uiowa.edu
Nature
|February 24, 2001
まとめ
科学者たちは,ラジオ信号を使って金星で雷を捜した. 地球からの信号を検出したにも関わらず,金星では同様の信号は見つかりませんでしたので,そこでの雷は珍しいか異なることを示唆しています.
科学分野:
- 惑星科学 惑星科学
- 大気物理学 大気物理学
- ラジオ天文学 ラジオ天文学
背景:
- 以前の低周波無線信号の検出は,金星で雷が鳴ったことを示唆していた.
- 雷からの可能性のある高周波無線信号も検出されていますが,その存在は依然として議論の余地があります.
研究 の 目的:
- 金星の大気中の雷の特徴である高周波無線信号の存在を調査するために.
- 金星の雷をめぐる論争を解決するために.
主な方法:
- 高周波 (0.125から16MHz) の無線信号を探すために,金星の2回近くを通過したカッシーニ宇宙船を利用した.
- 同じ器具は,その後の地球を横断飛行中に,地上からの雷の信号を成功裏に検出しました.
主要な成果:
- 金星から雷の特徴である高周波無線信号は検出されなかった.
- 地上の雷の信号は,地球から予想される速さで検出され,儀器の能力を検証しました.
結論:
- 検出された信号の欠如は,金星に雷が存在する場合,それは非常に稀であることを示唆しています.
- また,金星の稲妻は,地上の稲妻の特徴から著しく異なる可能性があります.
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