Entropy volume renderings for s15 f _heat1.00 3D at late times showing the development of the SASI. Four different postbounce times are shown, spaced 6 ms apart, from left to right. The shock itself is visible as the pale blue surfaces, as in Figure 2, and constant-density contours with a value of 10 ¹² g cm ⁻³ (magenta) mark the edge of the PNS. At this stage the shock shows clear spiral motion, as indicated by the spherical harmonic components shown in Figure 6.