RETRACTED:小惑星イトカワのX線光スペクトロメトリー ハヤブサによる
Tatsuaki Okada1, Kei Shirai, Yukio Yamamoto
1Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa 229-8510, Japan. okada@planeta.sci.isas.jaxa.jp
まとめ
小惑星イトカワのX線光スペクトロメトリにより,その元素の組成が明らかになった. 小惑星は小惑星です.
科学分野:
- 宇宙鉱物学と惑星科学.
- 小惑星サンプル分析と宇宙探査.
背景:
- 小惑星25143イトカワは,サンプルの帰還ミッションを対象とした近地小惑星です.
- 小惑星の組成を理解することで,初期の太陽系形成の洞察が得られます.
研究 の 目的:
- X線光スペクトロメトリを用いて小惑星25143イトカワの元素組成を決定する.
- イトカワの組成を,既知の隕石類と比較するために.
主な方法:
- X線光スペクトロメトリは,ハヤブサ宇宙船のX線スペクトロメーターを使用して行われました.
- データは,2005年11月19日の最初のタッチダウンで,太陽活動が強化された状態で収集されました.
主要な成果:
- 平均元素質量比が決定されました: Mg/Si = 0.78 ± 0.09 と Al/Si = 0.07 ± 0.03.
- イトカワの組成は,通常のコンドライト,特にLL-またはL-コンドライトと一致しています.
- 小惑星の表面では,地域的な構成の有意な変動は観察されなかった.
結論:
- 小惑星25143イトカワは,均質な組成を示しています.
- 構成からすると,イトカワは普通のコンドライトで,おそらくLL型またはL型である可能性が高い.
- 原始的なアコンドライトの分類を決定的に排除するためにさらなる分析が必要である.
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