Feo and Klp3A prevent collision trajectories of dividing nuclei in space and on 2D topologies. (A) Two neighboring spindles with division axes that are oblique. Nuclei separate along the spindle axis, which do not have an intersecting point and do not cause nuclear collision. (B) Two neighboring spindles with coplanar spindle axes. If these axes are not parallel, they will always form an intersection point. However, because of the short nuclear migration from the previous spindle center (∼14 µm), the nuclear diameter (∼5 µm), and the average interspindle distance (∼28 µm), two nonsibling nuclei will collide only if the relative angle α between spindle axes is ≤70°. (C) In a 2D topology of spindles with optimal packing, each spindle has six neighbors. In this configuration, and considering the geometric constraints shown in B, any orientation of spindle axis for the spindle in the center will lead to collisions with nonsibling nuclei. (D) Model of aster-mediated repulsion between neighboring nuclei on a colliding trajectory after mitosis. Astral microtubule cross-linking by Feo and Klp3A generates a repulsive mechanical element that deviates the direction of separating nuclei from the spindle axis.