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Updated: Jul 16, 2026
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Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
小惑星のYORP効果の直接検出
Stephen C Lowry1, Alan Fitzsimmons, Petr Pravec
1School of Mathematics and Physics, Queen's University Belfast, Belfast BT7 1NN, UK. s.c.lowry@qub.ac.uk
Science (New York, N.Y.)
|March 10, 2007
まとめ
ヤーコフスキー・オキーフ・ラデヴィフスキー・パダック (YORP) 効果は,小惑星のスピン速度の変化の直接的な証拠を提供します. 地球近傍小惑星2000 PH5の正確な観測は,その回転が継続的に増加していることを示し,YORP効果を確認しています.
科学分野:
- 太陽系ダイナミクス 太陽系ダイナミクス
- 小惑星物理学 小惑星物理学
- 観測天文学 観測天文学
背景:
- ヤーコフスキー・オキーフ・ラデヴスキー・パダック (YORP) 効果は,太陽系の小さな天体の回転に影響を与える理論化されたメカニズムです.
- これまでのYORP効果の証拠は間接的であり,決定的な観察的証拠がない.
研究 の 目的:
- 小惑星のスピン状態に対するYORP効果の影響の直接的な観測証拠を提供するために.
- 小さな近地小惑星のスピンレートの変化を正確に測定するために.
主な方法:
- 小惑星 (54509) 2000 PH5の精密な光学フォトメトリック観測を4年間行いました.
- 観測データを分析し,小惑星の自転速度と時間の経過による変化を決定しました.
- 引力トルク分析や近地アプローチモデリングを含むダイナミックシミュレーションを行い,代替説明を排除しました.
主要な成果:
- 小惑星2000 PH5.5の自転速度の継続的な増加が観察されました.
- 旋回速度の増加を量化すると,ドームガ/dt = 2.0 (+/-0.2) x 10(-4) 度/日二乗.
- 地球との衝突による重力トルクが観測されたスピン加速を説明できないことを実証した.
結論:
- 小惑星2000 PH5の観測されたスピン速度の増加は,YORP効果の直接的な証拠を提供します.
- ダイナミックシミュレーションは,スピン変化の原因としてYORP効果を支持します.
- 予測される小惑星2000 PH5は,将来,およそ20秒の回転周期に達する可能性がある.
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