Mass-radius diagram for known ultra-short period planets with mass and radius measurements more precise than 30% and having Earth/Neptune sizes and masses. Points are color-coded according to the incidental flux (in Earth units) received by the planet. TOI-1807 b is highlighted with a larger point and thick contours. For this plot, we used the TOI-1807 b’s mass obtained in case 1. The dashed colored lines are the theoretical mass-radius curves for different chemical compositions according to Zeng et al. (2019). The shaded area represents the maximum value of iron content predicted by collisional stripping (Marcus et al. 2010). Data from The Extrasolar Planets Encyclopaedia¹⁵.