撞击碎片粒子在木星的平流层中的撞击碎片
R A West1, E Karkoschka, A J Friedson
1Earth and Space Sciences Division, California Institute of Technology, Pasadena 91109.
概括
彗星舒迈克-莱维9号对木星的撞击产生了深色,富含硫和的有机气溶. 颗粒凝结解释了气溶的存在.
科学领域:
- 行星科学 行星科学
- 天文学 天文学
- 彗星科学 彗星科学
背景情况:
- 周期性彗星Shoemaker-Levy 9撞击了木星.
- 哈勃太空望远镜 (HST) 观测到了后果.
研究的目的:
- 分析撞击碎片的组成和物理特性.
- 了解气溶在撞击后的演变.
主要方法:
- 在HST上使用了广场行星摄像头2 (WFPC2).
- 分析光谱数据以确定粒子属性.
主要成果:
- 撞击碎片颗粒是深棕色的,富含硫和.
- 气溶体积达到了0.5公里半径的球体在撞击后的一天.
- 在光学厚的区域 (1-200 mbar) 中,平均粒子半径为0.15-0.3μm.
结论:
- 有机物质可能导致颗粒的颜色.
- 粒子凝固模型解释了在一个月内观察到的气溶演变.
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