The magnetic field lines drape around flux rope. The green surface is an isosurface of density 10^-17   g/cm^-3, which represents the flux rope. The red lines are the magnetic field lines. The colored sphere on the left represents part of the Sun′s surface. The blue and red area is the active region where we inserted a flux rope to initiate a CME. The pink line indicates the line from which we sampled the data.