Mean RV of the Fraunhofer lines scattered by the Earth’s sky as functions of time. Each chunk (separated by empty spaces) corresponds to a scan. The first scan taken on September 14, 2009 is not shown as it was taken before sunrise. In both plots, the thin gray line represents the theoretical variation of the sky-scattered solar lines according to the ephemeris (Earth’s rotation essentially). The abbreviation “cam” refers to the CCD camera’s number.