Rotations and densities of trans-Neptunian objectsD. Perna1, 2, 3, E. Dotto3, M. A. Barucci1, A. Rossi4, S. Fornasier1, 5, and C. de Bergh1
1 LESIA, Observatoire de Paris, 5 place Jules Janssen, 92195 Meudon Principal Cedex, France
2 Università di Roma Tor Vergata, Italy
3 INAF - Osservatorio Astronomico di Roma, Italy
4 ISTI-CNR, Pisa, Italy
5 Université Paris Diderot – Paris 7, France
Received 28 February 2009 / Accepted 12 July 2009
Context. Trans-Neptunian objects (TNOs) represent a new frontier in the study of our Solar System. In particular, the investigation of their rotational properties can provide important hints about their internal structure and collisional evolution.
Aims. We expand the limited sample of TNOs with known rotation rates, and improve the knowledge of the physical nature of these bodies.
Methods. We carried out photometric observations of 5 TNOs (144897 2004 UX10, 145451 2005 RM43, 145453 2005 RR43, 2003 UZ117, and 2003 UZ413) using the New Technology Telescope of the European Southern Observatory.
Results. We determined the spin rates of four targets, while only an estimation of the period was possible for 2003 UZ117.
Conclusions. From the computed rotational periods and the obtained light curve amplitudes of four TNOs, we derived the lower limit to their axis ratio a/b, and hence estimated their density. Combining our new results with literature data, we investigated the density statistics of the small bodies of the outer Solar System.
Key words: Kuiper Belt -- techniques: photometric
© ESO 2009