Magnetic field pile-up and draping at intermediately active comets: results from comet 67P/Churyumov-Gerasimenko at 2.0 AU

Abstract

The interaction between a comet and the impinging solar wind leads to modifications of the magnetic field in the environment of a comet. Among those, one finds magnetic field pile-up and draping, which reveal properties of the interaction and are known from previous cometary spacecraft missions. This work studies the magnetic field configuration at comet 67P/Churyumov-Gerasimenko at 2.0 AU. The data reveal a pile-up of the magnetic field and a draping signature nearly perpendicular to the original solar wind flow and the plane containing the solar wind flow and the interplanetary magnetic field. A comparison of the magnetic field data with a hybrid plasma simulation supports this idea of a plasma flow which is strongly deflected from the Sun-comet direction and which is in line with other plasma observations by the Rosetta Plasma Consortium.