Fig. 2: Planetary radius versus orbital period and planetary mass.
From: A young progenitor for the most common planetary systems in the Galaxy
a,b, Planetary radius versus orbital period (a) and planetary radius versus planetary mass (b) for the V1298 Tau system (red filled circles); error bars represent 1σ uncertainties. The low-density planets of the Kepler-51 system are shown for comparison (purple squares), along with kernel density estimates of the distributions of well-characterized exoplanets (shaded contours), drawn from the NASA Exoplanet Archive (n = 624 planets with mass and radius uncertainties less than 20%, P < 150 days and host Teff = 4,500–6,500 K to exclude M dwarfs). The parameters of the Kepler-51 planets were sourced from the ‘outside 2:1’ solution in Table 6 of ref. 27. Theoretical radius evolution tracks from ref. 29 are shown as vertical dashed lines. The terminal radii at 5 Gyr from that work are shown as open triangles. The colour indicates the assumed core mass (red for 5 M⊕ and black for 10 M⊕). The orientation represents the stellar extreme-ultraviolet activity level (upwards for high activity and downwards for low activity). The black dashed line in a depicts the observed location of the radius valley28. Theoretical mass–radius relations for different planet compositions from ref. 31 are shown in b as dashed lines. Grey dotted lines indicate theoretical mass–radius relations for Earth-like cores with H/He envelopes with various mass fractions from ref. 30, calculated for an age of 100 Myr and an insolation of 10 F⊕.
