523676 (2013 UL10): the first active red centaur E. Mazzotta Epifani, E. Dotto, S. Ieva, D. Perna, P. Palumbo, M. Micheli and E. Perozzi A&A, 620 (2018) A93 Published online: 04 December 2018 DOI: 10.1051/0004-6361/201731224