Observational Investigation of Dynamical and Photochemical Variability in the Venus Middle Atmosphere

金星和地球的大气层形成于太阳系早期的条件相当相似，但最终却截然不同。由于金星巨大的垂直范围和独特的热、化学和动力条件，它的大气以二氧化碳为主，这给观测带来了巨大的挑战。该项目是对金星中层（海拔70-100公里）和低层热层（海拔100-120公里）的观测研究，这些区域以复杂的氯、氧、硫和氢光化学为特征，以及从逆行流（与行星相反）的动态转变。（S旋转）在较低的高度到白天到晚上的环流。首席研究员和合作者将使用地面和机载望远镜，包括詹姆斯·克拉克·麦克斯韦望远镜（JCMT）、阿塔卡马大型毫米/亚毫米阵列（ALMA）和平流层红外天文观测台（SOFIA）来测量温度、风和分子物种的时空分布。目标是约束(1)化学和环流的时空变化，(2)中间层的光化学，以及(3)环流和成分梯度背后的物理。该项目更广泛的影响来自于它对理解类地行星的贡献，现在认为类地行星在太阳以外的恒星周围很常见；金星提供了最好的机会来了解一颗类地行星是如何进化成与地球非常不同的环境的。

The atmospheres of Venus and Earth formed in early solar system conditions that were fairly similar, but ended up very different. Venus's massive carbon dioxide dominated atmosphere presents substantial observational challenges due to its expansive vertical extent and distinct regimes of thermal, chemical, and dynamical conditions. This project is an observational study of the Venus middle mesosphere (at 70-100 km altitude) and lower thermosphere (100-120 km), regions characterized by complex chlorine, oxygen, sulfur, and hydrogen photochemistry, as well as a dynamical transition from retrograde flow (opposite to the planet?s rotation) at lower altitudes to dayside-to-nightside circulation above. The Principal Investigator and collaborators will use ground-based and airborne telescopes, including the James Clerk Maxwell Telescope (JCMT), the Atacama Large Millimeter/Submillimeter Array (ALMA), and the Stratospheric Observatory for Infrared Astronomy (SOFIA) to measure the spatial and temporal distribution of temperatures, winds, and molecular species. The goals are to constrain (1) the temporal and spatial variability in chemistry and circulation, (2) the photochemistry of the mesosphere, and (3) the physics underlying the circulation and compositional gradients. The broader impact of the project derives from its contribution to understanding Earth-like planets, which are now thought to be common around stars other than the Sun; Venus provides the best opportunity to understand how an Earth-like planet can evolve to an environment very unlike that of Earth.