Herschel/PACS 100 and 160 µm folded light curves of Quaoar. Panel a: 100 µm thermal light curve folded with the P = 8.876 h period. The red curve is the best-fit single-peak sine function. The black dots and curve represent the binned data. The different coloured dots correspond to different OBSIDs, as indicated in the legend. Panel b: 100 µm thermal light curve folded with the P = 17.752 h period. The red curve is a best-fit sine function, with a half-period (P = 8.876 h), and assuming equal half-amplitudes. Panel c: same as (b), but here the red curve is the best-fit second-order sine function, a combination of P = 8.876 h and P = 17.752 h components, i.e. allowing different amplitudes for the first and second half of the folded light curve. Panels d–f: Same as panels a–c, but using the 160 µm data.