当地的星际尘埃流的偏移由太阳辐射压力
M Landgraf1, K Augustsson, E Grün
1NASA Johnson Space Center, Mailcode SN2, Houston, TX 77058, USA. mlandgra@esoc.esa.de
Science (New York, N.Y.)
|December 22, 1999
概括
由于太阳辐射压力,星际尘埃粒在2-4AU之间不太常见. 这种压力是太阳引力的1.4-1.8倍,影响酸盐和有机耐火粒.
科学领域:
- *行星科学和天体物理学
- * 宇宙尘埃动力学
背景情况:
- * 了解星际尘埃的组成和分布对于行星的形成和进化至关重要.
- *以前的研究表明,太阳系内的尘埃种群存在差异.
研究的目的:
- * 为了研究在2~4 AU的日中心距离范围内观测到的星际尘埃颗粒的缺陷.
- * 确定负责观察到的尘埃粒分布的力量.
主要方法:
- *分析Ulysses和利略航天器上的尘埃探测器数据.
- * 模拟太阳辐射压力和太阳重力对各种组成和大小的尘埃粒的影响.
主要成果:
- *在4AU以外的区域相比,在2AU至4AU之间检测到显著的星际尘埃颗粒 (质量为1×10−17至3×10−16公斤) 缺乏.
- *太阳辐射压力需要是太阳引力的1.4到1.8倍,以转移这些粒.
- * 这些比率与天文酸盐,有机耐火材料和纯石墨颗粒 (直径为0.2-0.4微米) 的光学特性保持一致.
结论:
- *太阳辐射压力在塑造太阳系内部星际尘埃分布方面起着至关重要的作用.
- *观察到的尘埃缺陷与作用于酸盐,有机和石墨尘埃颗粒的力量一致.
- * 这一发现提供了对尘埃动态及其与星际环境中的恒星辐射相互作用的见解.
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