Marco Fenucci

Research


N-body choreographies

N-body choreographies are periodic solutions of the classical Newtonian N-body problem in which N equal masses follow each other around a fixed closed curve. The most famous orbit of this type is the Figure Eight solution, discovered first by C. Moore in 1993 in a numerical way. The rigorous proof of the existance of the Figure Eight were made by A. Chenciner and R. Montgomery in 1999. Some movies can be found here. Some computations I have done for the paper [1] can be found here, while computations I have done for the paper [4] can be found here.

Choreographies seem to exist also in other dynamical problems, for example in systems of charged particles (electrons and protons), moving under the Coulomb potential. Some computations I have done for the paper [2] can be found here.


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Asteroid Itokawa
Credit: ISAS, JAXA

Population of small asteroids

Asteroid population models are the main source of information about the number of objects in the size-range below a few thousands of meters. Main belt asteroids (MBAs) and near-Earth objects (NEOs) do not represent independent populations, as they are closely connected by evolutionary processes and dynamical transport mechanisms, associated to orbital resonances and semimajor axis drifts caused by non-gravitational perturbations. One of the objectives of the research project is to develop a new distribution model of small NEOs (down to 10/20 meters), which is compatible with the known observational constraints.

Moreover, a criticality index for near-Earth objects has to be defined. Such index should measure how much an asteroid is interesting to study, to explore and exploit, and also how easy it is to deflect. This classification is meant to guide the future exploration of small bodies, identifying which objects are more interesting to be studied and visited first.


Publications

  1. M.F., B. Novaković, D. Vokrouhlický, R. J. Weryk: 2021. Low thermal conductivity of the super-fast rotator (499998) 2011 PT, Astronomy and Astrophysics 647, A61. DOI: https://doi.org/10.1051/0004-6361/202039628.

  2. L. Asselle, M.F., A. Portaluri: 2020. Bifurcations of balanced configurations for the Newtonian n-body problem in R4, arXiv prepreint. Additional material for this paper can be found here.

  3. M.F., G. F. Gronchi: 2020. Symmetric constellations of satellites moving around a central body of large mass, arXiv prepreint.

  4. G. Lari, M. Saillenfest, M. F.: 2020. Long-term evolution of the Galileian satellites: the capture of Callisto into resonance, Astronomy and Astrophysics 639, A40. DOI: https://doi.org/10.1051/0004-6361/202037445.

  5. M. F., Á. Jorba: 2019. Braids with the symmetries of Platonic polyhedra in the Coulomb (N+1)-body problem, Communications in Nonlinear Science and Numerical Simulation, Vol. 83, DOI: https://doi.org/10.1016/j.cnsns.2019.105105.

  6. M. F., G. F. Gronchi: 2018. On the stability of periodic N-body motions with the symmetry of Platonic polyhedra, Nonlinearity, Vol. 31, Num. 11, pp 4935-4954. DOI: https://doi.org/10.1088/1361-6544/aad644.


Conferences and Meetings


Training schools


Visits and Seminars