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Sketch of the heliosphere and its constituents [click to enlarge]

The heliosphere is a giant circumsolar plasma cocoon with a diameter of the order of several hundred astronomical units. It shields the planets from a direct contact with the interstellar medium by deflecting the interstellar plasma flow, by efficiently ionizing neutral gas components and by reducing the flux of cosmic rays. The structure of the heliosphere is changing in time due to solar activity and to a changing interstellar environment.

Artist's conception of the solar magnetic field, with field lines shown as blue ribbons.
[click to enlarge]

Contemporary research considers the Sun and the heliosphere as an integrated system, whose parts should be considered separately but are tightly interconnected by, for example, the solar/heliospheric magnetic field.

An understanding of the heliosphere is not only desirable in view of its role as a shield protecting life on Earth but also as natural plasmaphysical laboratory in which many fundamental plasma physical process, like turbulent diffusion, stochastic acceleration or nonthermal heating by plasma waves, can be studied. Narrowing the focus from the global to the inner heliosphere leads directly to the field of Space Weather, i.e. the influence of the Sun on the interplanetary medium, in general, and the terrestrial magnetosphere and atmosphere, in particular.

Hubble telescope image showing an illuminated bow shock at another star. Credits: NASA, ESA, and The Hubble Heritage Team (STScI/AURA).
[click to enlarge]

Widening the focus enables one to consider the heliosphere as an example for astrospheres around other stars and brings one to consider the nature of the interstellar medium including the transport of cosmic rays within.

Fields covered in the group

Our research, which is partially carried out within large national and international collaborations like CAWSES or space missions like IBEX, is addressing several aspects of the outlined scenario; namely:
Solar Corona and Inner Heliosphere Large-scale Heliosphere Galactic Propagation of Cosmic Rays
Solar Corona/
Inner Heliosphere
Large-Scale Heliosphere/
Interaction with the ISM/CRs
Galactic Propagation of CRs/
Local Interstellar Spectra