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Published on: February 12, 2013
来自Shoemaker-Levy 9彗星与木星相撞的波浪
1Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena 91125, USA.
Nature
|April 20, 1995
概括
彗星舒迈克-莱维9号对木星的撞击揭示了大气波. 哈勃太空望远镜观测到的这些波浪表明木星大气中存在深层冲击和大量氧比.
科学领域:
- 行星科学 行星科学
- 大气物理学 大气物理学
- 彗星科学 彗星科学
背景情况:
- 彗星Shoemaker-Levy 9碎片与木星的碰撞为研究行星深层大气提供了独特的机会.
- 哈勃太空望远镜的图像捕捉到圆形环从撞击地点以450米/秒的速度扩散,长达2.5小时.
研究的目的:
- 为了研究彗星撞击后观察到的大气干扰的性质.
- 确定解释观察到的波浪现象的最合理的物理机制.
主要方法:
- 哈勃太空望远镜对木星撞击后大气层图像的分析.
- 模拟三种潜在的波浪干扰类型:声波,平流层重力波和被困重力波.
- 模拟波特征 (速度,振幅) 与观测数据的比较.
主要成果:
- 只有被困在假设的热层水云内的稳定层中的重力波与观察到的波速和振幅相匹配.
- 这种模型需要深度冲击和高度稳定的捕获层.
- 这些发现暗示木星的氧比率可能很大,大约是太阳比率的十倍,如果潮湿的对流产生了稳定的层.
结论:
- 被困在稳定的热带层中的重力波是观察到的撞击后现象最可能的解释.
- 彗星撞击可能深入木星大气层.
- 木星大气的组成,特别是O:H比率,可能与太阳的丰度有很大不同.
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