Autocorrelation of the power spectrum in three frequency ranges. The blue curve shows the low frequencies [10, 500] μHz, which are dominated by Jovian rotation, and optical path difference fluctuations of the interferometer, generated by temperature fluctuations. The black curve shows the frequency range dominated by the pointing errors [4450, 7350] μHz. The red curve shows the [900, 3800] μHz range, where we measure a double excess power. Only this last curve displays a modulation at about 160 ± 5 μHz, indicated with the grey region, as well as at its half value.