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MESSENGER observaciones de explosiones transitorias de electrones energéticos en la magnetosfera de Mercurio
George C Ho1, Stamatios M Krimigis, Robert E Gold
1The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA. george.ho@jhuapl.edu
Science (New York, N.Y.)
|October 1, 2011
Resumen
MESSENGER detectó electrones energéticos, pero no protones, cerca de Mercurio. El débil campo magnético de Mercurio impide la formación de cinturones de radiación como los que se encuentran en otros planetas.
Área de la Ciencia:
- Ciencias planetarias Ciencias planetarias.
- Física del espacio Física del espacio
- Física de la magnetosfera Física de la magnetosfera Física de la magnetosfera Física de la magnetosfera Física de la magnetosfera Física de la magnetosfera Física de la magnetosfera
Sus antecedentes:
- La nave espacial MESSENGER orbitaba Mercurio, un planeta con un campo magnético intrínseco débil.
- Comprender las magnetosferas planetarias y los cinturones de radiación es crucial para la exploración espacial.
Objetivo del estudio:
- Para investigar la presencia y las características de las partículas energéticas en la magnetosfera de Mercurio.
- Para determinar si Mercurio posee cinturones de radiación del tipo Van Allen.
Principales métodos:
- Análisis de los datos energéticos de electrones y protones (energías > 30 keV) de la nave espacial MESSENGER.
- Examen de la intensidad de las partículas, espectros de energía y distribuciones angulares.
Principales resultados:
- Los electrones energéticos (>30 keV) se detectaron con frecuencia en explosiones, mientras que los protones energéticos estaban ausentes.
- Las energías de los electrones a menudo superaban los 100 keV, con distribuciones que se extienden desde el ecuador hasta los polos.
- Las distribuciones angulares indicaron que los electrones no completaron las trayectorias de deriva completas alrededor de Mercurio.
Conclusiones:
- El débil campo magnético de Mercurio no soporta cinturones de radiación estables de tipo Van Allen.
- Las poblaciones de electrones energéticos observadas son distintas de las que se encuentran en otras magnetosferas planetarias.
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