小惑星"862アポロ"の自転の加速は,放射線トルクによるものです
Mikko Kaasalainen1, Josef Durech, Brian D Warner
1Department of Mathematics and Statistics, Rolf Nevanlinna Institute, PO Box 68, FI-00014 University of Helsinki, Finland. mikko.kaasalainen@helsinki.fi
Nature
|March 9, 2007
まとめ
小惑星から反射する太陽光によって引き起こされるヤルコフスキー・オキーフ・ラデヴスキー・パダック (YORP) 効果は,小惑星1862アポロの自転速度の変化を直接観測した. この発見は,YORP効果が小惑星の動力学に大きな影響を与えていることを確認しています.
科学分野:
- * 惑星科学 (惑星科学)
- * 天文学 (アストロノミー)
- * 軌道ダイナミクス
背景:
- * 小惑星の表面からの太陽光のアニゾトロピック反射と熱再放出が推進力 (ヤルコフスキー効果) を生み出します.
- * ヤーコフスキー効果は,物理的性質に基づいて小惑星の軌道ダイナミクスを変化させます.
- * 不規則な形状のボディの場合,この推進力はトルク (YORP効果) を生み出し,回転速度と軸の方向を変化させます.
研究 の 目的:
- * ヤルコフスキー・オキーフ・ラデヴィフスキー・パダック (YORP) 効果の直接的な観察証拠を提供するため.
- * 小惑星の回転進化におけるYORP効果の役割を調査する.
主な方法:
- *小惑星1862アポロのフォトメトリック光曲線分析.
- *小惑星の回転速度の変化を40年にわたってモニタリングする.
主要な成果:
- *小惑星1862アポロの回転速度の大きな変化が検出されました.
- *観測された変化は,YORPメカニズムによる予測と一致しています.
- * 回転速度の変化は,キロメートルの小惑星の40年以内に1回の余分な回転サイクルに相当します.
結論:
- * YORP効果は,小惑星1862アポロに作用する直接観測されています.
- * これは,小惑星のダイナミックな進化におけるYORP効果の重要な役割に対する強力な証拠を提供します.
- *この発見は,YORP効果が小惑星の自転に与える影響に関する理論的予測を裏付けている.
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