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通过旋转裂变形成小行星对
P Pravec1, D Vokrouhlický, D Polishook
1Astronomical Institute AS CR, Fricova 1, CZ-25165 Ondrejov, Czech Republic. ppravec@asu.cas.cz
Nature
|August 27, 2010
概括
小行星对是由旋转裂变形成的,其中一个母小行星迅速旋转并分开. 这个过程解释了观测到的质量比和旋转周期,支持了对二进制小行星形成的新模型.
科学领域:
- * 星球科学 星球科学
- * 天文学 * 天文学
- * 天体物理学 * 天体物理学
背景情况:
- *最近发现的小行星对具有相似的日心轨道,但并没有受到重力约束.
- *以前的轨道分析显示分离缓慢,但没有提供明确的形成机制.
- * 旋转裂变是假设,预测特定的质量比和旋转周期.
研究的目的:
- * 为了研究小行星对的形成机制.
- *通过分析小行星对属性来测试旋转裂变假设.
- * 为了确定裂变的临界质量比和旋转周期关系.
主要方法:
- *对一组小行星对进行了光度观测.
- *测量了小行星对的旋转周期和质量比.
- * 分析了数据,以将主体旋转周期与质量比相关联.
主要成果:
- * 质量比明显低于0.2的小行星原始体表现出快速旋转,接近临界裂变速度.
- *当质量比接近0.2时,初级的旋转周期会变长.
- *没有观察到超过0.2质量比的小行星对.
结论:
- *这些发现支持旋转裂变作为小行星对的主要形成机制.
- * 观测到的质量比和旋转周期之间的关系与裂变预测一致.
- * 质量比大于0.2的系统缺乏足够的能量来破坏,解释了它们的缺失.
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