Real-time evolution of a large-scale relativistic jet Josep Martí, Pedro L. Luque-Escamilla, Gustavo E. Romero, Juan R. Sánchez-Sutil and Álvaro J. Muñoz-Arjonilla A&A, 578 (2015) L11 Published online: 16 June 2015 DOI: 10.1051/0004-6361/201526355