When we consider the motion of a celestial body (e.g. a planet), the gravitational attraction of the main body (e.g. the Sun) can be insufficient to obtain an orbit that approximates the real one with the wanted accuracy. Just considering the perturbation of a third body we can obtain very interesting effects on the motion, such as in the case of mean motion resonances of asteroids or between satellites. For my research activity I am studying the Laplace resonance between the Galilean satellites of Jupiter (Io, Europa, Ganymede and Callisto): the resonant interaction between the moons and the dissipative effects due to the tides with Jupiter, make the satellites' orbits evolve. This mechanism is well know in celestial mechanics theory, but its magnitude in the case of Jupiter is still a discussion matter into the scientific community.
There are several interplanetary missions that are operating in the Solar System. Apart from NASA (National Aeronautics and Space Administration), also ESA (European Space Agency) makes great efforts in its own space program. JUICE mission is a future European mission that will explore the Jovian system, obtaining different kind of data on the Galilean satellites. Departing from the orbit determination software ORBIT14, developed by the Celestial Mechanics Group of Pisa, I am performing different simulations in order to study the performances of the mission. Apart from some common dynamical parameters, such as the moons' gravitational coefficients, I am interested in the determination of the position of the Galilean satellites and the dissipation due to the tidal forces.
In the case of a volcanic eruption the magma flows from the cone to the areas below. A possible model that can predict the path of the fluid is described by the Shallow Water equations, for which it is considered a low fluid thickness and a 2-dimensional motion. In order to obtain realistic simulations, it is necessary to consider a suitable rheology, that adds friction forces to the model. Recently I worked on a project of the INGV, under the supervision of Dr. de' Michieli Vitturi, where we developed a numerical solver for the Shallow Water equations (IMEX_SfloW2D software), in order to study Etna eruption events.
Dirkx D., Gurvits L.I., Lainey V., Lari G., Milani A., Cimó G., Bocanegra-Bahamon T.M., Visser P.N.A.M. (2017). On the contribution of PRIDE-JUICE to Jovian system ephemerides. Planetary and Space Science 147, 14-27. DOI: https://doi.org/10.1016/j.pss.2017.09.004
Saillenfest M., Lari G. (2017). The long-term evolution of known resonant trans-Neptunian objects. Astronomy and Astrophysics 603, A79. DOI: https://doi.org/10.1051/0004-6361/201730525
CELMEC VII, Balletti Park Hotel, San Martino al Cimino (Italy), 4-8 September 2017. In this conference I gave a presentation titled "On the determination of Jupiter system's energy dissipation with JUICE space mission data".
Fifth JUICE Science Working Team Meeting, ESTEC, Noordwijk (Netherlands), 28-29 January 2015
First 3GM Meeting, Dipartimento di Ingegneria Meccanica e Aerospaziale, Roma (Italy), 15-16 January 2015. In this meeting I gave a presentation titled "Laplace Resonance and energy dissipation in the Jovian system"
AGU Fall Meeting, Moscone Center, San Francisco (U.S.A., California), 15-19 December 2014
Joint Juno/Cassini Jupiter-Saturn interiors meeting, Hotel Marriot Marquis, San Francisco (U.S.A., California), 14 December 2014
In the period from 1st May to 31th July 2016 I visited the Institut de Mécanique Céleste et de Calcul des Éphémérides (IMCCE) at the Observatoire de Paris, Paris (France). Under the supervision of Prof. Valery Lainey, I worked on the development of an orbit determination software for the ESA space mission JUICE.
In the week from 30th November to 5th December 2015 I visited the Department of Mathematics of the Hokkaido University, Sapporo (Japan). During this visit I gave a presentation titled "A semianalitical secular model of the Galilean satellites dynamics".
In the week from 28th August to 2nd September 2017 I attended the "Satellite Dynamics and Space Missions" summer school, at the Balletti Park Hotel, San Martino al Cimino (Italy).
In the week from 12th to 16th September 2016 I attended the "Planetary Interiors" summer school, at the Gran Sasso Science Institute (GSSI), L'Aquila (Italy). In this occasion I presented a poster titled "The dynamics of the Galilean satellites and JUICE mission opportunities".