Extended Data Fig. 2: Folded Kepler transits of Kepler-138 b, c, and d, and search for the transit of Kepler-138 e.
From: Evidence for the volatile-rich composition of a 1.5-Earth-radius planet
The four panels show the corrected light curve of Kepler-138 (open circles) folded in a 2 day window around the expected transit epochs of Kepler-138 b, c, d, and e from the photodynamical fit (see Methods). Transit models corresponding to the median retrieved planet parameters are superimposed to the data (solid colored lines), conservatively assuming an Earth-like composition to estimate the radius of Kepler-138 e. The transits of Kepler-138 b, c, and d are detected in the Kepler light curve, but while Kepler-138 e should be larger than Kepler-138 b, its transit is not detected. We interpret this as originating from a likely non-transiting configuration of Kepler-138 e’s orbit, with an inclination of ≲ 89∘ consistent with the photodynamical solution, too low to occult the stellar disk from our perspective.
