Connotea
CiteULike
del.ico.us
BibSonomyAbstract
GEOPHYSICAL RESEARCH LETTERS,
VOL. 36,
L04106,
5 PP., 2009
doi:10.1029/2008GL036207
Sodium-ion pickup observed above the magnetopause during MESSENGER's first Mercury flyby: Constraints on neutral exospheric models
Heliophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
Heliophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
Heliophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
Goddard Earth Sciences and Technology Center, University of Maryland, Baltimore County, Baltimore, Maryland, USA
Department of Astronomy, University of Maryland, College Park, Maryland, USA
Institute of Geophysics and Planetary Physics, University of California, Los Angeles, California, USA
Institute of Geophysics and Planetary Physics, University of California, Los Angeles, California, USA
Single-particle tracings of sodium pickup ions launched upstream of Mercury's magnetopause are used to investigate the access of these ions to the magnetosphere and set limits on the distribution of neutral sodium about the planet during the first MESSENGER flyby. The transport of pickup ions is modeled using flow velocity and magnetic fields from a three-dimensional magnetohydrodynamic simulation. Extensive penetration of pickup ions into the magnetosphere is found in the post-noon and dusk local time sectors due to the northward interplanetary magnetic field at the time of MESSENGER's first flyby. It is concluded that: (1) pickup of magnetosheath photoions may be an important source of hot planetary ions within the magnetosphere; and (2) the sodium ions in the magnetosheath observed by MESSENGER must originate from an extended neutral exosphere due to ion sputtering and/or to a partially escaping distribution generated by photon-stimulated desorption with yields modified by regolith trapping.
Received 2 October 2008; accepted 21 January 2009; published 25 February 2009.
Citation: (2009), Sodium-ion pickup observed above the magnetopause during MESSENGER's first Mercury flyby: Constraints on neutral exospheric models, Geophys. Res. Lett., 36, L04106, doi:10.1029/2008GL036207.
Cited By