a) Quiet Sun Mg ii h and k spectra, averaged over ≈80 000 pixels. The inset shows the components of the k-line (h-line labelled using the same convention). Dotted lines show the rest wavelengths: 2796.35 Å (k-line) and 2803.53 Å (h-line) b) 1330 Å SJI from 13:35 UT. The blue box surrounds the NR, the red dotted lines are the slit positions, and the yellow regions are the pixels that were used to create the averaged quiet Sun spectra.