Threshold shear stress τ_t over ambient pressure for the dust aggregates at 0.018 g and for glass spheres at 1 g from earlier experiments. The solid lines are fits of Eq. (1) to the data. The free parameters for dust aggregates, received from the fit, can be found in Eq. (5), and the free parameters for the larger glass spheres can be found at the end of Sect. 2. For more details on the glass sphere measurements, we refer to Demirci et al. (2020a).