An overview of the observational detections of an asymmetric CO₂ absorption feature. The top-left panel shows the phase-resolved absorption spectra from 1.6 to 5.3 μm, with highlighted regions corresponding to molecular absorption features and continuum regions. The phase curves for these regions are plotted in the upper-right panel. Each phase curve is shown with the best-fitting phase-curve model (as discussed in Sections 3.4 and 3.5) as well the model reflected across the phase = 0.5 (the substellar point). The middle-left panel shows the difference in the chi-squared values of the original and reflected model fits. The red dashed line represents the threshold for a significant detection. Only the 4.2 μm CO₂ feature exceeds this threshold. The lower panels show the light curve of the CO₂ feature (above) and the depth of the absorption feature as a function of phase (below). Both panels show a western nightside offset that occurs ∼50 minutes before the antistellar point.