Detrimental effects of weigntlessness are no longer expected to hinder successful mitosis. Experiments in space and on the fast clinostat give no hints of this. Nevertheless we are thinking of a g sensitivity during the process of chromosome condensation and distribution. The time course of nuclear division in microplasmodia of the slime mold Physarum polycephalum was investigated under 0 g simulation on the fast rotating clinostat in comparison to 1 g controls. The result of this experiment is: A significant shortening of mitosis under 0 g simulation compared to 1 g controls.