Variability of Lyα signal compared with variation in thermodynamic temperature and surface brightness maps produced from data collected by HFI on the Planck space observatory in selected Alice rows. The data shown as a function of Galactic Latitude were acquired during the Alice scan that traversed the sky mostly along Galactic Longitude, but we note that it was not necessarily a constant Galactic longitude. The same is true for the data shown as a function of Galactic longitude. The units for the Planck observations are K_cmb at 353 GHz and MJy sr⁻¹ at 545 GHz and 857 GHz. The intensity of the Planck data is scaled to match the signal at Lyα wavelengths.