Phase coverage as a function of the orbital period using all photometric data obtained with SSO for LP 890-9. The effective coverage of 86% is the integral of the black curve. The orbital periods of planets b and c are shown as orange and red lines, respectively. The figure also shows the empirical (optimistic) HZ in green, i.e. the region between the ‘Recent Venus’ and ‘Early Mars’ limits (Kopparapu et al. 2013, 2014, and Sect. 8.3).