UC Santa Cruz

My dissertation research uses tides to link a satellite’s orbit and interior to discover what happened in its past. I have developed numerical models that include tides on the planet and satellite to see how the satellite’s orbital distance, eccentricity, inclination, and obliquity vary with time. My first chapter seeks to explain how the orbit of Callisto, the fourth major moon of Jupiter, became inclined. We propose that if Callisto had passed through resonances with its inner neighbor, Ganymede, in its past, then Callisto’s orbit could have received a kick that we still observe today. The second chapter focuses on the long-standing problem of how the Moon’s orbit became inclined. We tested several proposed mechanisms, and the most likely scenario is that the Sun’s gravitational perturbations destabilized the Moon’s orbit causing it to become tilted. The third chapter takes observations of Titan’s spin state and calculates the amount of tidal heating taking place in its interior at the present-day. Given how dissipative Titan is, we found that its interior needs to have a layer of low viscosity, deformable ice. Furthermore, we calculated that Titan’s orbit is changing rapidly, suggesting a recent event made Titan’s orbit eccentric and inclined.