SSOF model of order 93 for HD 26965 which identifies H-alpha variation. Top left: The telluric and stellar templates are shown above in gray and blue while the telluric feature vector is shown below (orange). This vector is dominated by changing H₂O transmission between observations. Bottom left: the observed air mass (black) and telluric feature scores (orange) as a function of time. The H₂O signal is not correlated with air mass but clearly identified in multiple orders (see Figure 8). Top right: the telluric and stellar templates are shown above in gray and blue while the stellar feature vector is shown below (turquoise). This vector is dominated by the changes in H-alpha. Bottom right: the stellar feature scores as a function of time. The scores for the H-alpha feature vector (turquoise) are correlated with the H-alpha variation measured by NEID’s DRP (green), although SSOF’s scores are a bit noisier due to the inclusion of the entire order. Some NEID measurements of CaI lines are also shown. The residuals between v_⋆,93 and ﹩{v}_{\star }^{{\mathtt{SSOF}}}﹩ are shown in Figure 11.