在木星的浅层电风中发出小小的闪电
Heidi N Becker1, James W Alexander2, Sushil K Atreya3
1Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA. Heidi.N.Becker@jpl.nasa.gov.
Nature
|August 8, 2020
概括
木星
科学领域:
- 星球科学
- 大气科学
- 血物理
背景情况:
- 之前的木星闪电观测受限于相机的灵敏度和距离.
- 估计闪光速率为每公里4×10−3,空间范围为30公里.
- 闪光被解释为5巴附近的潮湿对流的痕迹.
研究的目的:
- 报告朱诺航天器对木星闪电的新观测结果.
- 用前所未有的细节来描述闪电的能量,持续时间和速度.
- 调查木星闪电的大气起源和产生机制.
主要方法:
- 使用朱诺航天器的光学仪器来探测闪电.
- 分析的闪光能量在105108之间.
- 测量闪光持续时间为5.4毫秒,闪光间隔时间为毫秒.
主要成果:
- 观测到木星闪电速率为6.1×10−2每公里2/年,比之前报告的高出一个数量级.
- 检测到空间范围较小的闪光,
- 测量到的闪电能量相当于地球上的闪电.
结论:
- 星闪电的发生率远高于此前的估计.
- 闪电在2巴以上的水平表明水对闪电产生并不重要.
- 在木星大气层中可能存在多种发电机制, 需要对大气对流和组成进行进一步的研究.
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