Mass–radius diagram of confirmed Earth-sized planets with masses up to 20 M_⊕. Data were taken from NASA Exoplanet archive⁵. The mass–radius relations were taken from Zeng et al. (2016). From top to bottom: black solid lines denotes a pure water, pure rock, and pure iron composition. The grey dashed lines between the solid lines represent mass–radius relations for water-rock and rock-iron composites. The red solid line indicates the lower limit of a planet radius as a result of collisional stripping (Marcus et al. 2010). K2-265 b has a composition consistent with a rocky terrestrial planet.