金星大气层的夜侧云顶循环
Kiichi Fukuya1, Takeshi Imamura2, Makoto Taguchi3
1Department of Earth and Planetary Science, The University of Tokyo, Tokyo, Japan.
Nature
|July 22, 2021
概括
维纳斯
科学领域:
- 星球科学
- 大气科学
- 航空学
背景情况:
- 维纳斯的大气循环是很难理解的, 特别是在夜边.
- 之前的研究缺乏所有当地时间的全面风力数据.
- 了解金星的大气动力学是理解地球行星演变的关键.
研究的目的:
- 描述金星的大气循环,包括热潮和哈德利循环.
- 调查金星大气超旋转的原因.
- 提供有关金星云顶的综合风力数据.
主要方法:
- 使用来自阿卡苏基金星轨道器的红外热图像.
- 采用云追踪技术来确定大约65公里的风速.
- 收集所有当地时间的数据, 包括夜间时间.
主要成果:
- 在金星的夜侧观察到明显的赤道流动.
- 在没有哈德利循环影响的情况下确定热潮的速度结构.
- 发现半日潮的幅度足以维持大气超旋转.
结论:
- 哈德利循环的北极分支位于云顶上方,而赤道分支则位于云层内.
- 热潮在维纳斯大气的超级旋转中起着重要作用.
- 这些发现提供了对其他天体大气超旋转的见解.
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