MAVEN‐STATIC Observations of Ion Temperature and Initial Ion Acceleration in the Martian Ionosphere
Abstract Though ion escape to space is an important mechanism for atmospheric loss at Mars, the processes that accelerate ions to escape velocity have not been fully identified and quantified. The lowest altitude where suprathermal planetary ions appear is an important source region for ion escape,...
| Published in: | Geophysical Research Letters |
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| Main Authors: | , , , , |
| Format: | Article |
| Language: | English |
| Published: |
Wiley
2022-09-01
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| Subjects: | |
| Online Access: | https://doi.org/10.1029/2022GL100182 |
| _version_ | 1850047055489138688 |
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| author | K. G. Hanley C. M. Fowler J. P. McFadden D. L. Mitchell S. Curry |
| author_facet | K. G. Hanley C. M. Fowler J. P. McFadden D. L. Mitchell S. Curry |
| author_sort | K. G. Hanley |
| collection | DOAJ |
| container_title | Geophysical Research Letters |
| description | Abstract Though ion escape to space is an important mechanism for atmospheric loss at Mars, the processes that accelerate ions to escape velocity have not been fully identified and quantified. The lowest altitude where suprathermal planetary ions appear is an important source region for ion escape, where electromagnetic forces and waves begin to energize ions to escape velocity. We have conducted a statistical study of O2+ distribution functions measured by Mars Atmosphere and Volatile EvolutioN SupraThermal And Thermal Ion Composition in order to identify the region where suprathermal tails appear. At all solar zenith angles, suprathermal ions appear just above the exobase region, where the mean free path between collisions exceeds the neutral gas scale height. O2+ temperature profiles are also presented. We also investigate the effects of crustal magnetism, finding that crustal fields protect planetary plasma on the dayside and enhance energization on the nightside. |
| format | Article |
| id | doaj-art-e704ec0d1db54b808b977a84bb381c39 |
| institution | Directory of Open Access Journals |
| issn | 0094-8276 1944-8007 |
| language | English |
| publishDate | 2022-09-01 |
| publisher | Wiley |
| record_format | Article |
| spelling | doaj-art-e704ec0d1db54b808b977a84bb381c392025-08-20T00:28:41ZengWileyGeophysical Research Letters0094-82761944-80072022-09-014918n/an/a10.1029/2022GL100182MAVEN‐STATIC Observations of Ion Temperature and Initial Ion Acceleration in the Martian IonosphereK. G. Hanley0C. M. Fowler1J. P. McFadden2D. L. Mitchell3S. Curry4Space Sciences Laboratory University of California Berkeley Berkeley CA USADepartment of Physics and Astronomy West Virginia University Morgantown WV USASpace Sciences Laboratory University of California Berkeley Berkeley CA USASpace Sciences Laboratory University of California Berkeley Berkeley CA USASpace Sciences Laboratory University of California Berkeley Berkeley CA USAAbstract Though ion escape to space is an important mechanism for atmospheric loss at Mars, the processes that accelerate ions to escape velocity have not been fully identified and quantified. The lowest altitude where suprathermal planetary ions appear is an important source region for ion escape, where electromagnetic forces and waves begin to energize ions to escape velocity. We have conducted a statistical study of O2+ distribution functions measured by Mars Atmosphere and Volatile EvolutioN SupraThermal And Thermal Ion Composition in order to identify the region where suprathermal tails appear. At all solar zenith angles, suprathermal ions appear just above the exobase region, where the mean free path between collisions exceeds the neutral gas scale height. O2+ temperature profiles are also presented. We also investigate the effects of crustal magnetism, finding that crustal fields protect planetary plasma on the dayside and enhance energization on the nightside.https://doi.org/10.1029/2022GL100182Mars ionosphereion energizationsuprathermal ionsion temperature |
| spellingShingle | K. G. Hanley C. M. Fowler J. P. McFadden D. L. Mitchell S. Curry MAVEN‐STATIC Observations of Ion Temperature and Initial Ion Acceleration in the Martian Ionosphere Mars ionosphere ion energization suprathermal ions ion temperature |
| title | MAVEN‐STATIC Observations of Ion Temperature and Initial Ion Acceleration in the Martian Ionosphere |
| title_full | MAVEN‐STATIC Observations of Ion Temperature and Initial Ion Acceleration in the Martian Ionosphere |
| title_fullStr | MAVEN‐STATIC Observations of Ion Temperature and Initial Ion Acceleration in the Martian Ionosphere |
| title_full_unstemmed | MAVEN‐STATIC Observations of Ion Temperature and Initial Ion Acceleration in the Martian Ionosphere |
| title_short | MAVEN‐STATIC Observations of Ion Temperature and Initial Ion Acceleration in the Martian Ionosphere |
| title_sort | maven static observations of ion temperature and initial ion acceleration in the martian ionosphere |
| topic | Mars ionosphere ion energization suprathermal ions ion temperature |
| url | https://doi.org/10.1029/2022GL100182 |
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