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Updated: May 2, 2026
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Bringing the Visible Universe into Focus with Robo-AO
Published on: February 12, 2013
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火星でオーロラの発見
Jean-Loup Bertaux1, François Leblanc, Olivier Witasse
1Service d'Aéronomie du CNRS/IPSL, BP 3, Verrières-le-Buisson, 91371, France. bertaux@aerov.jussieu.fr
Nature
|June 10, 2005
まとめ
科学者たちは,これまで見たことのないような,火星でユニークなオーロラを発見しました. この火星のオーロラは,地殻の磁場異常によって局所され,制御され,地球や巨大惑星のオーロラとは異なる.
科学分野:
- 惑星科学は惑星科学である.
- 大気物理学 大気物理学
- 宇宙物理学 宇宙物理学
背景:
- オーロラは,有電粒子相互作用によって引き起こされる惑星の大気中の視覚的放射です.
- オーロラ活動は,地球,四つの巨大惑星,そして金星で知られている.
- 火星のオーロラは以前は確認されていなかったが,金星は夜間放射を散布している.
研究 の 目的:
- 火星の大気中のオーロラの発見を報告するために.
- この新たに発見された火星のオーロラの性質を特徴づけるために.
- 火星のオーロラを他の惑星で見られるオーロラと区別するために.
主な方法:
- マース・エクスプレス宇宙船に搭載された紫外線スペクトロメーターSPICAMを利用した.
- 火星の大気中の紫外線放射を分析した.
主要な成果:
- 火星の大気中のオーロラの存在を確認した.
- 地球や巨大惑星のオーロラとは異なる新しいタイプのオーロラを特定しました.
- 火星のオーロラを高度に集中し,局所的に特徴付けました.
- 火星のオーロラ放射は,地殻の磁場異常によって制御されていることが決定されました.
結論:
- 火星のオーロラは,太陽系における新種のオーロラ現象を表しています.
- 地球や巨大惑星とは異なり,火星のオーロラは,極の固有の磁場線に縛られていません.
- 火星のオーロラの局所的な性質は,惑星の地殻の磁場における異常に起因する.
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