Constraints on the eccentricities of K2-19 b and c. Left panel: 2D joint posterior of ﹩e\cos \omega ﹩ and ﹩e\sin \omega ﹩ for K2-19b (blue) and K2-19c (green). The contours represent the 1σ and 2σ levels. Right panel: draws from our credible models showing e_b against e_c. While either planet may have zero eccentricity, both may not. This arises from our tight constraint on the dynamical variable Y₁ described in Section 4.