[SEMINARI] Solar Wind Interaction with the Local Interstellar Medium: Achievements and Challenges, N. V. Pogorelov

[Enric Marco]

Solar Wind Interaction with the Local Interstellar Medium: Achievements 
and Challenges

N. V. Pogorelov

Physics Department and Center for Space Plasma and Aeronomic Research 
University of Alabama in Huntsville, USA

Seminari del departament d'Astronomia i Astrofísica

Dilluns 18 octubre 2010

15:30

Resum

 From the astrophysical perspective, the solar wind (SW) interaction 
with the local interstellar medium (LISM) is a particular case of the 
flow around an ejecting star placed into surrounding medium. I will 
describe the mathematical and physical statements of this problem and 
demonstrate how the interstellar magnetic field shapes the astropause. 
While the Voyager 1 and 2 spacecraft are exploring the boundaries of the 
heliosphere, our newest spacecraft, the Interstellar Boundary Explorer 
(IBEX) has started exploring the outermost reaches of the heliosphere, 
but from an orbit at 1 AU measuring the fluxes of energetic neutral 
atoms (ENAs) created in the boundary regions separating the heliosphere 
from the LISM. The first IBEX results revealed a sky-spanning “ribbon” 
of unexpectedly intense emissions of ENAs that had not been predicted 
previously by any physical model. For the next 5-10 years, heliophysics 
research is faced with an extraordinary opportunity that cannot be soon 
repeated. This is to make in situ measurements of the SW from the Sun to 
the heliospheric boundaries and, at the same time, extract information 
about the global behavior of the evolving heliosphere through ENA 
observations by the IBEX. In this talk, the effects are described of 
unsteady SW and interstellar magnetic field (ISMF) pressure of the shape 
of the heliopause and the terminations shock. We analyze the ISMF 
influence on the deflection of the neutral hydrogen flow in the inner 
heliosphere from its original direction in the unperturbed LISM and on 
the position of the ENA ribbon. It is shown that the ISMF direction 
strongly correlates with the ribbon location, which is useful for 
constraining the properties of the interstellar medium in the immediate 
vicinity of the heliospheric boundary.

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/------------------------------------\
 Dr. Enric Marco
 Departament d'Astronomia i Astrofísica
 Facultat de Física
 Universitat de València
 C/  Dr. Moliner, 50
 46100 Burjassot, Spain
 Phone: (34)-96-354-3069
 Fax:(34)-96-354-3084
 enric.marco en uv.es
 http://www.uv.es/marco
 http://www.uv.es/aulaastronomia
 http://www.uv.es/daa
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