Dayside (top) and nightside (bottom) effective temperatures of the atmosphere of WASP-189 b as a function of the Bond albedoA_B and the heat redistribution efficiency ε. The lower limit of the colour scale is set to 1000 K for abetter visualisation. White dotted lines show isothermal profile across the (A_B, ε) plane. The dayside and nightside temperatures are equal when ε = 1 and both go down to 0 K in the limit A_B → 1. If the dayside temperature is 3000 K, then the Bond albedo values range from 0 to ~0.38, with corresponding values of the heat redistribution efficiency from ~0.59 to 0, respectively. In such a case, the maximum nightside temperature would be ~ 2250 K.