  High-quality spectropolarimetric data of SN 2002ap were obtained with the ESO
Very Large Telescope Melipal (+ FORS1) at 3 epochs that correspond to -6, -2,
and +1 days for a V maximum of 9 Feb 2002. The polarization spectra show three
distinct broad features at 400, 550, and 750 nm that evolve in shape, amplitude
and orientation in the Q-U plane. The continuum polarization grows from nearly
zero to ~0.2 percent. The 750 nm feature is polarized at a level > 1 %. We
identify the 550 and 750 nm features as Na I D and OI 777.4 nm moving at about
20,000 km/s. The blue feature may be Fe II. We interpret the polarization
evolution in terms of the impact of a bipolar flow from the core that is
stopped within the outer envelope of a carbon/oxygen core. Although the
symmetry axis remains fixed, as the photosphere retreats by different amounts
in different directions due to the asymmetric velocity flow and density
distribution, geometrical blocking effects in deeper, Ca-rich layers can lead
to a different dominant axis in the Q-U plane. We conclude that the features
that characterize SN 2002ap, specifically its high velocity, can be accounted
for in an asymmetric model with a larger ejecta mass than SN 1994I such that
the photosphere remains longer in higher velocity material. The characteristics
of "hypernovae" may be the result of orientation effects in a mildly
inhomogeneous set of progenitors, rather than requiring an excessive total
energy or luminosity. In the analysis of asymmetric events with spherically
symmetric models, it is probably advisable to refer to "isotropic equivalent"
energy, luminosity, ejected mass, and nickel mass.
