Location of slices S₃ and S₄ (top row) chosen for the time-distance analysis of AIA 304, 171, and 193 Å presented in the panels a–c, respectively. These slices were selected for the analysis of loop expansion and contraction. Different expanding and contracting loops are shown by dashed lines in the middle and bottom rows. The white vertical dashed line indicates the onset time of the eruption and the time of the top row images. The loop systems in the direction of slices S₃ and S₄ are labeled in panels e and h, respectively. A movie of AIA 304 Å is available online.