Example of telluric line fits for the O₂ band in a single Wolf 294 spectrum. The top panel displays the residual telluric spectrum (black dots) after dividing the science spectrum by the stellar template, and the best-fit telluric model (green dots) derived with molecfit. The subplots illustrate the individual telluric lines (top) and the residuals (bottom, black dots), with dashed red lines marking a 2% deviation between data and model. The standard deviation σ of the residuals is also shown in each subplot.