DOI: 10.1002/2017JA024938
Scopus记录号: 2-s2.0-85041010829
论文题名: A Sporadic Topside Layer in the Ionosphere of Mars From Analysis of MGS Radio Occultation Data
作者: Mayyasi M. ; Withers P. ; Fallows K.
刊名: Journal of Geophysical Research: Space Physics
ISSN: 21699380
出版年: 2018
卷: 123, 期: 1 起始页码: 883
结束页码: 900
语种: 英语
英文关键词: ionosphere
; Mars
; plasma layers
英文摘要: The topside ionosphere of Mars is subject to dynamic interactions between the planet and the surrounding space environment. Significant variations in its structure have been observed that have not been consistently investigated or explained. All 5,600 ionospheric profiles obtained by the Mars Global Surveyor Radio Science experiment are analyzed here to systematically characterize a topside ionospheric layer that is visible in ~50% of the observations. For simplicity, we refer to this layer of plasma as the M3 layer and find that it is located, on average, ~ 40 km above the main ionospheric peak and reaches average maximum concentrations of ~ 9 × 103 cm−3. The properties of this topside feature, derived from the Mars Global Surveyor (MGS) radio occultation data set, are compared with existing findings of topside plasma enhancements at Mars observed in other data sets. Newly found characteristics in the topside layer properties are shown to support that solar radiation is not the main production source of this layer, in contrast to the behavior expected for the lower ionospheric photochemical layers at Mars. The analysis presents a set of trends that must be explained by theory for the formation mechanisms. These trends do not support some popular explanations such as Kelvin-Helmholtz instabilities and crustal magnetic field localization. Occurrence rates suggest a more constant source, such precipitation from the solar wind, and possible subsequent heating. These findings shed light on the enigmatic behavior of the topside Martian ionosphere and its surrounding dynamics. ©2018. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/114858
Appears in Collections: 气候减缓与适应
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作者单位: Center for Space Physics, Boston University, Boston, MA, United States; Department of Astronomy, Boston University, Boston, MA, United States
Recommended Citation:
Mayyasi M.,Withers P.,Fallows K.. A Sporadic Topside Layer in the Ionosphere of Mars From Analysis of MGS Radio Occultation Data[J]. Journal of Geophysical Research: Space Physics,2018-01-01,123(1)