Tidal diagrams. Tidal diagrams for transiting giant planets from Bonomo et al. (2017a). Open circles denote planets on circular orbits with σ_e < 0.05. Markers shown with pluses are planets with undertermined eccentrities, i.e. σ_e > 0.05. Most of these are consistent with e = 0. Triangles represent planets with significant, but small eccentricities e < 0.1, and squares are eccentric systems ≥0.1. Adhering to this notation we have shown the planets in our sample with the corresponding marker. However, we have colour coded them for clarity. Created from the catalogue Bonomo et al. (2017b). Left. Tidal diagram: solid and dashed lines show the position of a planet with a separation of a = a_R and a = 2a_R, respectively (a_R being the Roche limit), and radius R_p = 1.2 R_J. The dotted line is a circularisation isochrone for a planet with P = 3 d, Q′_p = 10⁶, and e = 0. It should be noted that Eq. (1) in Bonomo et al. (2017a) used to create the dotted line should have π in the numerator instead of the denominator (A. S. Bonomo priv. comm.). Right. Modified tidal diagram: dotted, dashed, and solid lines denote the 1, 7, and 14 Gyr circularisation timescales, respectively, assuming e = 0 and Q′_p = 10⁶.