Sketch of the asymmetric WASP-76 b atmosphere and the spatial distribution of its constituents as suggested by the cross-correlation functions obtained for H₂O (blue), HCN (red), and NH₃ (yellow) during ingress (top right), the first and second halves of the transit (bottom right and bottom left, respectively), and egress (top left). All CCFs were obtained at the expected K_P for WASP-76 b (196 km s⁻¹). The Doppler shift of the signals is indicated by the colored arrows in the sketch. That is, blueshifted signals (H₂O and NH₃) are marked by arrows pointing at the observer, whereas the redshifted HCN signal point towards the star. The leading and trailing limbs during the planet transit are indicated by the letters “L” and “T”, respectively.