The propagation properties of coronal mass ejections (CMEs) are crucial to
predict its geomagnetic effect. A newly developed three dimensional (3D) mask
fitting reconstruction method using coronagraph images from three viewpoints
has been described and applied to the CME ejected on August 7, 2010. The CME's
3D localisation, real shape and morphological evolution are presented. Due to
its interaction with the ambient solar wind, the morphology of this CME changed
significantly in the early phase of evolution. Two hours after its initiation,
it was expanding almost self-similarly. CME's 3D localisation is quite helpful
to link remote sensing observations to in situ measurements. The investigated
CME was propagating to Venus with its flank just touching STEREO B. Its
corresponding ICME in the interplanetary space shows a possible signature of a
magnetic cloud with a preceding shock in VEX observations, while from STEREO B
only a shock is observed. We have calculated three principle axes for the
reconstructed 3D CME cloud. The orientation of the major axis is in general
consistent with the orientation of a filament (polarity inversion line)
observed by SDO/AIA and SDO/HMI. The flux rope axis derived by the MVA analysis
from VEX indicates a radial-directed axis orientation. It might be that locally
only the leg of the flux rope passed through VEX. The height and speed profiles
from the Sun to Venus are obtained. We find that the CME speed possibly had
been adjusted to the speed of the ambient solar wind flow after leaving COR2
field of view and before arriving Venus. A southward deflection of the CME from
the source region is found from the trajectory of the CME geometric center. We
attribute it to the influence of the coronal hole where the fast solar wind
emanated from.Comment: ApJ, accepte