| DOI: | 10.1002/2015GL065079
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| 论文题名: | A hot flow anomaly at Mars |
| 作者: | Collinson G.; Halekas J.; Grebowsky J.; Connerney J.; Mitchell D.; Espley J.; DiBraccio G.; Mazelle C.; Sauvaud J.-A.; Fedorov A.; Jakosky B.
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| 刊名: | Geophysical Research Letters
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| ISSN: | 0094-8458
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| EISSN: | 1944-8189
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| 出版年: | 2015
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| 卷: | 42, 期:21 | | 起始页码: | 9121
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| 结束页码: | 9127
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| 语种: | 英语
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| 英文关键词: | foreshock
; HFA
; hot flow anomaly
; Mars
; MAVEN
; unmagnetized planet
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| Scopus关键词: | Earthquakes
; Ionosphere
; Magnetosphere
; NASA
; Solar wind
; Transients
; Foreshock
; HFA
; Hot flow anomaly
; Mars
; MAVEN
; Planets
; diameter
; electron
; ionosphere
; magnetic field
; magnetization
; magnetosphere
; Martian atmosphere
; perturbation
; solar wind
; spacecraft
; Venus
|
| 英文摘要: | One of the most important modes of planet/solar wind interaction are "foreshock transients" such as hot flow anomalies (HFAs). Here we present early observations by the NASA Mars Atmosphere and Volatile EvolutioN spacecraft, confirming their presence at Mars and for the first time at an unmagnetized planet revealing the underlying ion perturbations that drive the phenomenon, finding them to be weaker than at magnetized planets. Analysis revealed the HFA to be virtually microscopic: the smallest on record at ∼2200 km across and commensurate with the local proton gyroradius, resulting in a much stronger perturbation in solar wind protons than alpha particles. As at Venus, despite being physically diminutive, the HFA is still large (0.66 RM) when compared to the relative size of the induced magnetosphere. Given the associated order of magnitude decrease in solar wind dynamic pressure (411 pPa ⇠70 pPa), we find that HFAs at Mars have the potential to directly impact the topside ionosphere. We thus hypothesize that the loss of a planetary magnetic dynamo left Mars far more vulnerable to the pressure pulses resulting from HFAs and related foreshock transients. © 2015. American Geophysical Union. All Rights Reserved. |
| URL: | https://www.scopus.com/inward/record.uri?eid=2-s2.0-84955178755&doi=10.1002%2f2015GL065079&partnerID=40&md5=ac8c7e002ee62c68db282aa77ba8fc07
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| Citation statistics: |
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| 资源类型: | 期刊论文
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| 标识符: | http://119.78.100.158/handle/2HF3EXSE/8074
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| Appears in Collections: | 科学计划与规划
气候变化与战略
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作者单位: | NASA Goddard Spaceflight Center, Greenbelt, MD, United States
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| Recommended Citation: | |
Collinson G.,Halekas J.,Grebowsky J.,et al. A hot flow anomaly at Mars[J]. Geophysical Research Letters,2015-01-01,42(21).
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