Nucleus of the active Centaur C/2011 P2 (PANSTARRS) E. Mazzotta Epifani, D. Perna, E. Dotto, P. Palumbo, M. Dall’Ora, M. Micheli, S. Ieva and E. Perozzi A&A, 597 (2017) A59 Published online: 22 December 2016 DOI: 10.1051/0004-6361/201628405