Spectral variability on primitive asteroids of the Themis and Beagle families: space weathering effects or parent body heterogeneity? S. Fornasier1, C. Lantz1, D. Perna1, H. Campins2, M.A. Barucci1, D. Nesvorny3 1 LESIA, Observatoire de Paris, PSL Research University, CNRS, Univ. Paris Diderot, Sorbonne Paris Cit´e, UPMC Univ. Paris 06, Sorbonne Universit´es, 5 Place J. Janssen, 92195 Meudon Pricipal Cedex, France 2 Department of Physics and Astronomy, University of Central Florida, Orlando, Florida 32816-2385, USA. 3 Department of Space Studies, Southwest Research Institute, Boulder, CO 80302, USA Submitted to Icarus: July 2015 e-mail:
[email protected]; fax: +33145077144; phone: +33145077746 Manuscript pages: 40; Figures: 15 ; Tables: 4 Running head: The Themis-Beagle primitive families Send correspondence to: Sonia Fornasier arXiv:1601.05277v1 [astro-ph.EP] 20 Jan 2016 LESIA-Observatoire de Paris Batiment 17 5, Place Jules Janssen 92195 Meudon Cedex France e-mail:
[email protected] fax: +33145077144 Preprint submitted to Icarus April 17, 2018 phone: +33145077746 2 Spectral variability on primitive asteroids of the Themis and Beagle families: space weathering effects or parent body heterogeneity? S. Fornasier1, C. Lantz1, D. Perna1, H. Campins2, M.A. Barucci1, D. Nesvorny3 Abstract Themis is an old and statistically robust asteroid family populating the outer main belt, and resulting from a catastrophic collision that took place 2.5±1.0 Gyr ago. Within the old Themis family a young sub-family, Beagle, formed less than 10 Myr ago, has been identified. We present the results of a spectroscopic survey in the visible and near infrared range of 22 Themis and 8 Beagle families members.