Publication Date:
2008-07-05
Description:
Observations by MESSENGER show that Mercury's magnetosphere is immersed in a comet-like cloud of planetary ions. The most abundant, Na+, is broadly distributed but exhibits flux maxima in the magnetosheath, where the local plasma flow speed is high, and near the spacecraft's closest approach, where atmospheric density should peak. The magnetic field showed reconnection signatures in the form of flux transfer events, azimuthal rotations consistent with Kelvin-Helmholtz waves along the magnetopause, and extensive ultralow-frequency wave activity. Two outbound current sheet boundaries were observed, across which the magnetic field decreased in a manner suggestive of a double magnetopause. The separation of these current layers, comparable to the gyro-radius of a Na+ pickup ion entering the magnetosphere after being accelerated in the magnetosheath, may indicate a planetary ion boundary layer.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Slavin, James A -- Acuna, Mario H -- Anderson, Brian J -- Baker, Daniel N -- Benna, Mehdi -- Gloeckler, George -- Gold, Robert E -- Ho, George C -- Killen, Rosemary M -- Korth, Haje -- Krimigis, Stamatios M -- McNutt, Ralph L Jr -- Nittler, Larry R -- Raines, Jim M -- Schriver, David -- Solomon, Sean C -- Starr, Richard D -- Travnicek, Pavel -- Zurbuchen, Thomas H -- New York, N.Y. -- Science. 2008 Jul 4;321(5885):85-9. doi: 10.1126/science.1159040.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Heliophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA. james.a.slavin@nasa.gov〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18599776" target="_blank"〉PubMed〈/a〉
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
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Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
