The analysis of the rotational properties of the small bodies in the outer Solar System is a useful tool for retrieving information on the internal structure of the observed objects and for having hints on the collisional evolution state of the whole population. The sample of known rotational rates is still rater limited, including about 60 Trans-Neptunian Objects (TNOs) and a dozen of Centaurs. In order to increase the available data, in the framework of the ESO Large Program 178.C-0036 (P.I.: M. A. Barucci), we carried out at ESO-NTT (La Silla, Chile) photometric observations of 2 Centaurs (12929 1999 TZ1 and 95626 2002 GZ32) and 10 TNOs (42355 Typhon, 47932 2000 GN171, 65489 Ceto, 90568 2004 GV9, 120132 2003 FY128, 144897 2004 UX10, 145451 2005 RM43, 145453 2005 RR43, 2003 UZ117 and 2003 UZ413). Applying the method based on the Fourier analysis of the light curves, developed by Harris et al. 1989 (Icarus, 77, 171), rotational synodic periods were computed. We determined the spin rate for seven objects and we confirmed previously published periods of other two bodies. The computed rotational periods and the obtained light curve amplitudes allowed us to estimate the axis ratio a/b, and hence the density of these nine objects. Putting together our results and already published ones, we investigated density statistics of the small bodies of the outer Solar System. The obtained complete results will be presented and discussed.
Light Curves and Densities of Centaurs and Trans-Neptunian Objects from the ESO Large Program
Rossi A;
2008
Abstract
The analysis of the rotational properties of the small bodies in the outer Solar System is a useful tool for retrieving information on the internal structure of the observed objects and for having hints on the collisional evolution state of the whole population. The sample of known rotational rates is still rater limited, including about 60 Trans-Neptunian Objects (TNOs) and a dozen of Centaurs. In order to increase the available data, in the framework of the ESO Large Program 178.C-0036 (P.I.: M. A. Barucci), we carried out at ESO-NTT (La Silla, Chile) photometric observations of 2 Centaurs (12929 1999 TZ1 and 95626 2002 GZ32) and 10 TNOs (42355 Typhon, 47932 2000 GN171, 65489 Ceto, 90568 2004 GV9, 120132 2003 FY128, 144897 2004 UX10, 145451 2005 RM43, 145453 2005 RR43, 2003 UZ117 and 2003 UZ413). Applying the method based on the Fourier analysis of the light curves, developed by Harris et al. 1989 (Icarus, 77, 171), rotational synodic periods were computed. We determined the spin rate for seven objects and we confirmed previously published periods of other two bodies. The computed rotational periods and the obtained light curve amplitudes allowed us to estimate the axis ratio a/b, and hence the density of these nine objects. Putting together our results and already published ones, we investigated density statistics of the small bodies of the outer Solar System. The obtained complete results will be presented and discussed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
