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Scattering And Absorption of Light in Planetary Regoliths
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小惑星21 Lutetia:低質量,高密度
M Pätzold1, T P Andert, S W Asmar
1Rheinisches Institut für Umweltforschung, Abteilung Planetenforschung, an der Universität zu Köln, 50931 Cologne, Germany. martin.paetzold@uni-koeln.de
まとめ
ローゼッタ宇宙船のデータは,小惑星21 Lutetiaが1,700 × 10 ^ 18 kgの質量と3,4 × 10 ^ 3 kg / m ^ 3の散発密度を有し,その構成に関する洞察を提供していることを明らかにしました.
科学分野:
- 惑星科学は惑星科学である.
- 小惑星研究研究.
- 宇宙ミッションの分析
背景:
- 小惑星21 Lutetiaは,小惑星の構成と形成を理解するための重要なターゲットです.
- 過去の研究では,21のルテシアの正確な質量と密度測定が欠けていました.
研究 の 目的:
- 小惑星21 Lutetiaの質量を正確に決定するために.
- 内部構造と組成を推論するために,21 Lutetiaの散発密度を計算します.
主な方法:
- ロゼッタ宇宙船が21 Lutetiaを飛行した際のラジオ信号から得られたドップラーシフトデータを利用した.
- 余剰周波数観測に適した最小二乗を適用し,ルテシア以外のドップラー貢献を修正した.
- ロゼッタのOSIRISカメラから集積された体積データを集積して,体積密度を計算する.
主要な成果:
- 小惑星21 Lutetiaの質量を (1.700 ± 0.017) × 10^18 kg.と決定しました.
- 21 ルテシアの散発密度を (3.4 ± 0.3) × 10^3 kg/m^3.3) として計算しました.
- これらの測定は,小惑星の組成と内部研究のための重要なデータを提供します.
結論:
- 21 Lutetiaの正確な質量と密度は,宇宙船の測定によって確立されています.
- 決定された質量密度は,小惑星の内部構成と構造に関する重要な手がかりを提供します.
- この研究は,C型小惑星とその太陽系における位置についての理解を深める.
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