Spatial distributions of the helium mass fractions in SBS 0335−052 derived from the He I 4471, 5876, and 6678 Å emission‐line intensities. The intensities of the He I emission lines in (a) are corrected for fluorescent and collisional enhancement with an electron number density ﹩N_{e}﹩(He II) and an optical depth τ(λ3889) derived self‐consistently from the observed He I 3889, 4471, 5876, 6678, and 7065 Å emission‐line intensities. The intensities of the He I emission lines in (b) are corrected only for collisional enhancement with an electron number density ﹩N_{e}﹩(S II). The 1 σ error bars are shown only for the He mass fraction derived from the He I 5876 Å emission line. They are larger in (b) because of the large uncertainties in the determination of ﹩N_{e}﹩(S II).