Paranal atmosphere transmission function T(λ) for AM = 1 as evaluated from full-Moon spectra taken with UVES before the eclipse, following the reduction process described in Sect. 6.2. The UVES reduction pipeline automatically removes from all individual spectra tabulated values for the Rayleigh, aerosol and ozone signatures at the corresponding airmass of the observation. These signatures therefore do not appear here as for HARPS (Fig. 4). A weak residual curvature of the continuum (≈5% maximum at 7800 Å, with no resemblance to a residual signature of ozone or Rayleigh) was fitted with a second-order function. The spectrum shown here is normalized to this fit to have a flat continuum at 1 (horizontal line). The O₂γ, A, and B bands are clearly seen (in red), the other bands are due to H₂O (in blue).