P21A-2074
MAVEN observations of magnetic reconnection in the Martian magnetotail
Tuesday, 15 December 2015
Poster Hall (Moscone South)
Yuki Harada1, Jasper S Halekas2, James P McFadden3, David L Mitchell3, Christian Xavier Mazelle4, John E P Connerney5, Jared R Espley5, Davin E Larson1, Dave A Brain6, Laila Andersson7, Gina A DiBraccio8, Glyn Collinson9, Roberto Livi3, Takuya Hara1, Suranga Ruhunusiri10 and Bruce Martin Jakosky11, (1)Space Sciences Laboratory, Berkeley, CA, United States, (2)University of Iowa, Physics and Astronomy, Iowa City, IA, United States, (3)University of California Berkeley, Berkeley, CA, United States, (4)University Paul Sabatier Toulouse III, Toulouse Cedex 09, France, (5)NASA Goddard Space Flight Center, Greenbelt, MD, United States, (6)University of Colorado at Boulder, Laboratory for Atmospheric and Space Physics, Boulder, CO, United States, (7)University of Colorado at Boulder, Boulder, CO, United States, (8)NASA Goddard Space Flight Center, Solar System Exploration Division, Greenbelt, MD, United States, (9)NASA Goddard Space Flight Center, Heliophysics Sci. Div., Greenbelt, MD, United States, (10)University of Iowa, Iowa City, IA, United States, (11)Laboratory for Atmospheric and Space Physics, Boulder, CO, United States
Abstract:
Magnetic reconnection is a fundamental process that changes magnetic field topology and converts magnetic energy into particle energy. Although reconnection may play a key role in controlling ion escape processes at Mars, the fundamental properties of local physics and global dynamics of magnetic reconnection in the Martian environment remain unclear owing to the lack of simultaneous measurements of ions, electrons, and magnetic fields by modern instrumentation. Here we present comprehensive MAVEN observations of reconnection signatures in the near-Mars magnetotail. The observed reconnection signatures include (i) Marsward bulk flows of H+, O+, and O2+ ions, (ii) counterstreaming ion beams along the current sheet normal direction, (iii) Hall magnetic fields, and (iv) trapped electrons with two-sided loss cones. The measured velocity distribution functions of different ion species exhibit mass-dependent characteristics which are qualitatively consistent with previous multi-species kinetic simulations and terrestrial tail observations. The MAVEN observations demonstrate that the near-Mars magnetotail provides a unique environment for studying multi-ion reconnection.
