Despite the observed signs of big impacts on the surface of Ceres, there is no confirmed collisional family associated with this dwarf planet. Carruba et al. (2016) proposed a sample of 156 asteroids as candidates to be members of a Ceres’ collisional family after a dynamical and photometric study.
Our main objective is to study the connection between Ceres and a total of 14 observed asteroids among the sample proposed by Carruba et al. (2016), to explore their genetic relationships with Ceres. We obtained visible spectra of these 14 asteroids using the OSIRIS spectrograph at the 10.4m Gran Telescopio Canarias (GTC), located at the El Roque de Los Muchachos Observatory (La Palma, Spain), managed by the Instituto de Astrofísica de Canarias (IAC).
We computed spectral slopes in two different wavelength ranges, from 0.49 to 0.80 μm and from 0.80 to 0.92 μm, to compare the obtained values with those in Ceres’ surface computed by Rousseau et al (2020) using the VIR instrument on-board the NASA Dawn spacecraft. We have also calculated the slopes in the same range for Ceres’ ground-based observations collected from the literature.
Among the results we present the spectra and the taxonomy of 14 observed asteroids. We derived that only 2 asteroids are spectrally compatible with Ceres’ surface. Further analysis of those two asteroids indicates that they are spectrally young and thus less likely to be members of Ceres’ family.
All in all, our results indicate that most of the 14 observed asteroids are not likely to belong to a Ceres’ collisional family. Despite two among them are spectrally compatible with Ceres’ young surface, further considerations should be evaluated to confirm/reject their origin from Ceres.
Carruba, V., Nesvorny, D., Marchi, S., & Aljbaae, S. 2016 Monthly Notices of the Royal Astronomical Society, 458, 1117
Rousseau, B., De Sanctis, M.C., Raponi, A., et al. 2020, A&A, 642, A74
Rizos, J.L., de Leon, J., Licandro, J., et al. 2019, Icarus, 328, 69