Estimation of the spatial structure of a detached magnetic flux rope at Mars based on simultaneous MAVEN plasma and magnetic field observations. Issue 21 (5th November 2015)

• Record Type: Journal Article
• Authors: Hara, Takuya; Mitchell, David L.; McFadden, James P.; Seki, Kanako; Brain, David A.; Halekas, Jasper S.; Harada, Yuki; Espley, Jared R.; DiBraccio, Gina A.; Connerney, John E. P.; Andersson, Lailla; Mazelle, Christian; Jakosky, Bruce M.
• Is Part Of: Geophysical research letters. Volume 42:Issue 21(2015:Nov.)
• Page Start: 8933
• Page End: 8941
• Publication Date: 2015-11-05
• Subjects: MAVEN -- Mars -- Flux rope -- Grad‐Shafranov equation -- Atmospheric escape -- Crustal magnetic field; Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1002/2015GL065720
• Languages: English
• ISSNs: 0094-8276

Abstract

Abstract: Simultaneous Mars Atmosphere and Volatile EvolutioN mission (MAVEN) plasma and magnetic field observations reveal a detached magnetic flux rope in the Martian induced magnetosphere. The flux rope was identified by an increase in the magnetic field amplitude accompanied by smooth vector rotations. In addition, MAVEN observed a pronounced ion composition change across the structure, with solar wind ions dominating outside and planetary ions dominating within. Grad‐Shafranov reconstruction is applied to determine the two‐dimensional spatial structure of the flux rope. The event occurred near the dusk terminator, downstream from strong crustal magnetic fields. One possibility is that the flux rope was created by magnetic reconnection associated with interplanetary and/or crustal magnetic fields. A weak interplanetary coronal mass ejection (ICME) arrived at Mars a few hours before the event. A pressure pulse and turbulent magnetic fields due to the ICME might be responsible for driving magnetic reconnection to detach the flux rope from the crustal source. Key Points: First detection by MAVEN of a detached flux rope at Mars Detached flux rope includes planetary origin heavy ion populations Observed location is downstream from the strong crustal magnetic fields