  We review relationships between coronal mass ejections (CMEs), EIT post
eruption arcades, and the coronal neutral line associated with global magnetic
field and magnetic clouds near the Earth. Our previous findings indicate that
the orientation of a halo CME elongation may correspond to the orientation of
the underlyig flux rope. Here we revisit these preliminary reports by comparing
orientation angles of elongated LASCO CMEs, both full and partial halos, to the
post eruption arcades. Based on 100 analysed events, it was found that the
overwhelming majority of halo CMEs are elongated in the direction of the axial
field of the post eruptio arcades. Moreover, this conclusion also holds for
partial halo CMEs as well as for events that originate further from the disk
center. This suggests that the projection effect does not drastically change
the appearance of full and partial halos and their imagesstill bear reliable
information about the underlying magnetic fields. We also compared orientations
of the erupted fields near the Sun and in the interplanetary space and found
that the local tiltof the coronal neutral line at 2.5 solar radii is well
correlated with the magnetic cloud axis measured near the Earth. We suggest
that the heliospheric magnetic fields significantly affect the propagating
ejecta. Sometimes, the ejecta may even rotate so that its axis locally aligns
itself with the heliospheric current sheet.
