地球与行星物理论评（中英文）2023，Vol.54Issue(1)：91-99,9.DOI:10.19975/j.dqyxx.2022-051
基于MAVEN卫星的火星逃逸面温度研究:日变化与太阳活动性变化
MAVEN-based investigation of Martian exobase temperatures:Diurnal and solar cycle variations
摘要
Abstract
The exobase is a key concept for understanding atmospheric escape and evolution on Mars. With the aid of neutral density data measured via the Neutral Gas and Ion Mass Spectrometer onboard the Mars Atmo-sphere and Volatile Evolution spacecraft, we calculated the exobase temperatures of four relatively abundant spe-cies on Mars: CO2, O, N2, and CO. Our calculations revealed that the exobase temperatures are highly variable, with median temperatures of 174, 152, 195, and 193 K for CO2, O, N2, and CO, respectively. Moreover, the calcu-lated exobase temperatures for the four species increased systematically with an increase in the exobase altitude or a decrease in the exobase density. Further investigations indicated strong diurnal and solar cycle variations in the exobase temperature:(1) the exobase temperature on the day side was higher than that on the night side, revealing a maximum temperature near the local time of 14 h and a minimum temperature near the local time of 2 h;and (2) the exobase temperatures of the four species increased with the solar extreme ultraviolet (EUV) flux, a feature that was restricted to the day side and absent on the night side, where non-solar energy inputs are likely important. These variations originate from the varying degrees of upper atmospheric heating on Mars in response to the different so-lar EUV energy inputs.关键词
火星/大气逃逸/逃逸面Key words
Mars/atmospheric escape/exobase分类
天文与地球科学引用本文复制引用
顾浩,曹雨田,李子川,付梦昊,黄旭,孙铭阳..基于MAVEN卫星的火星逃逸面温度研究:日变化与太阳活动性变化[J].地球与行星物理论评（中英文）,2023,54(1):91-99,9.基金项目
This research was supported by the National Natural Science Foundation for Young Scientists of China(Grant No.42105120) （Grant No.42105120）
