New constraints on Ioʹs and Jupiterʹs tidal dissipation

Although the quest for tidal accelerations among the Galilean satellites has been ongoing since the beginning of the last century, no real agreement has been found so far. Using a numerical approach, we simulate the effect of tidal interactions on the evolution of Ioʹs motion during the last century. We show how these tidal effects can vanish during the fit process to observational data. By testing different values of dissipation within Io and Jupiter, we show that a non-detection of significant Ioʹs orbital acceleration does not imply a large dissipation within Jupiter, and we suggest an upper bound value ( ϕ surf ⩽ 7  W m −2 ) for the dissipation rate within Io.