Dust temperature a) and column density b) maps of B68 derived by line-of-sight SED fitting as described in Sect. 3.1. The temperature minimum attains 11.9 K and is offset by 5″ from the column density peak. The four positions from which we extracted the individual SEDs shown in Fig. 5 are indicated with  + . The central column density is N_H = 2.7 × 10²² cm^-2. The coordinates are given in arcminutes relative to the centre of the column density distribution, i.e. RA , Dec = −23°49′51″.