SOHO/LASCO/C2 difference image obtained from the images taken at 02:00:54 and 02:12:54 UT. The white arrows indicate the location in the plane-of-sky of the portion of the shock front moving westward (as seen from Earth) that did not follow the same evolution as the eastward front fitted with the ellipsoid. Northwest and southwest streamers shown in Figure 2(c) experienced significant deflection as the CME expanded over these latitudes. As discussed in the text, the front of the CME was distorted from an ellipsoid due to the different propagation conditions in this region.