Model isochrones from MIST (Choi et al. 2016) of varying ages, shown in terms of their average density (upper panel) and radius (lower panel). The upper panel compares stellar mean densities to those of Ceres and Earth. Stars denser than typical rocky bodies can disrupt these objects by tides. The lower panel compares the tidal radius, r_t (Eq. (1)), to stellar radii in units of R_⊙. In this case, stars more compact than r_t can disrupt an object without swallowing it whole. These isochrones show that as stars cool and collapse to their main sequence radii, low-mass stars (≲0.5 M_⊙) become denser than typical rocky planets and planetesimals, meaning that they can tidally disrupt these objects.