本文主要研究内容
作者(2019)在《Variability of the Martian ionosphere from the MAVEN Radio Occultation Science Experiment》一文中研究指出:The Martian ionosphere is produced by a number of controlling processes, including solar extreme ultraviolet radiation(EUV)and X-ray ionization, impact ionization by precipitating electrons, and day-to-night transport. This study investigates the structural variability of the Martian ionosphere with the aid of the radio occultation(RO) experiments made on board the recent Mars Atmosphere and Volatile Evolution(MAVEN) spacecraft. On the dayside, the RO electron density profiles are described by the superposition of two Chapman models, representing the contributions from both the primary layer and the low-altitude secondary layer. The inferred subsolar peak electron densities and altitudes are 1.24×105cm-3 and 127 km for the former, and 4.28×104cm-3 and 97 km for the latter,respectively, in general agreement with previous results appropriate for the low solar activity conditions. Our results strengthen the role of solar EUV and X-ray ionization as the driving source of plasma on the dayside of Mars. Beyond the terminator, a systematic decline in ionospheric total electron content is revealed by the MAVEN RO measurements made from the terminator crossing up to a solar zenith angle of 120°. Such a trend is indicative of day-to-night plasma transport as an important source for the nightside Martian ionosphere.
Abstract
The Martian ionosphere is produced by a number of controlling processes, including solar extreme ultraviolet radiation(EUV)and X-ray ionization, impact ionization by precipitating electrons, and day-to-night transport. This study investigates the structural variability of the Martian ionosphere with the aid of the radio occultation(RO) experiments made on board the recent Mars Atmosphere and Volatile Evolution(MAVEN) spacecraft. On the dayside, the RO electron density profiles are described by the superposition of two Chapman models, representing the contributions from both the primary layer and the low-altitude secondary layer. The inferred subsolar peak electron densities and altitudes are 1.24×105cm-3 and 127 km for the former, and 4.28×104cm-3 and 97 km for the latter,respectively, in general agreement with previous results appropriate for the low solar activity conditions. Our results strengthen the role of solar EUV and X-ray ionization as the driving source of plasma on the dayside of Mars. Beyond the terminator, a systematic decline in ionospheric total electron content is revealed by the MAVEN RO measurements made from the terminator crossing up to a solar zenith angle of 120°. Such a trend is indicative of day-to-night plasma transport as an important source for the nightside Martian ionosphere.
论文参考文献
论文详细介绍
论文作者分别是来自Earth and Planetary Physics的,发表于刊物Earth and Planetary Physics2019年04期论文,是一篇关于,Earth and Planetary Physics2019年04期论文的文章。本文可供学术参考使用,各位学者可以免费参考阅读下载,文章观点不代表本站观点,资料来自Earth and Planetary Physics2019年04期论文网站,若本站收录的文献无意侵犯了您的著作版权,请联系我们删除。