Premium
Sodium recycling at Europa: what do we learn from the sodium cloud variability?
Author(s) -
Cipriani F.,
Leblanc F.,
Witasse O.,
Johnson R. E.
Publication year - 2008
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2008gl035061
Subject(s) - sputtering , sodium , exosphere , desorption , ion , plasma , chemistry , analytical chemistry (journal) , atomic physics , materials science , physics , adsorption , thin film , nanotechnology , environmental chemistry , organic chemistry , quantum mechanics
We study the ejection of sodium atoms from Europa's surface by both magnetospheric ion and electron sputtering and desorption stimulated by UV solar photons. The depletion of the surface by ejection and its enrichment by redeposition of sodium atoms are described. The redistribution of sodium atoms at the surface induced by photo‐stimulated desorption from the dayside and by sputtering ejection from the trailing hemisphere cannot explain the observed variation of the Na emission brightness. However, a transient increase of the sputtering rate due to a plasma injection may explain such an increase. The relationship between the sodium surface content and the sodium exosphere are also discussed.