通过辐射扭矩加速小行星1862阿波罗的旋转速度
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
概括
由太阳光反射小行星驱动的Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) 效应被直接观察到改变了小行星1862 Apollo的旋转速度. 这一发现证实YORP效应显著影响小行星动态.
科学领域:
- * 星球科学 星球科学
- * 天文学 * 天文学
- * 轨道动力学 轨道动力学
背景情况:
- *来自小行星表面的阳光反射和热再发射产生推进力 (雅科夫斯基效应).
- * 亚科夫斯基效应改变了基于物理性质的小行星轨道动态.
- *对于形状不规则的车体,这种推进产生扭矩 (YORP效应),改变旋转速率和轴方向.
研究的目的:
- * 提供关于Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) 效应的直接观察证据.
- * 为了研究YORP效应在小行星旋转进化中的作用.
主要方法:
- *对小行星1862阿波罗进行光度曲线分析.
- * 监测小行星旋转速度在40年内发生的变化.
主要成果:
- * 探测到小行星1862阿波罗的旋转速度发生显著变化.
- *观察到的变化与YORP机制的预测一致.
- *旋转速率的变化相当于一个千米大小的小行星在40年内额外一次旋转周期.
结论:
- * YORP效应已经直接观察到对小行星1862阿波罗的作用.
- *这为YORP效应在小行星动态进化中的重要作用提供了有力的证据.
- *这些发现证实了关于YORP效应对小行星旋转的影响的理论预测.
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