Distribution of ³²S/³⁴S ratios from 112 sources in the Milky Way. The background image is the structure of the Milky Way from the artist's impression (Credit: NASA/JPL-Caltech/ESO/R. Hurt). The ³²S/³⁴S isotope ratios with corrections of opacity derived in this work from ¹³CS/¹³C³⁴S and the double isotope method in the J = 2−1 transition are plotted as circles and stars, respectively. The triangles indicate the results from the CMZ obtained by Humire et al. (2020). The red symbol ⊙ indicates the position of the Sun. The color bar on the right-hand side indicates the range of the ³²S/³⁴S ratios.