[1] European Southern Observatory, Alonso de Córdova 3107, Santiago, Chile
[2] Universidade de São Paulo, Dept. de Astronomia, Rua do Matão 1226, São Paulo,05508-090, Brazil
[3] Department of Physics, Durham University, South Road, Durham,DH1 3LE, United Kingdom
[4] INAF, Osservatorio Astronomico di Padova, Vicolo dell'Osservatorio 5, Padova,35122, Italy
[5] Research School of Astronomy and Astrophysics, Australian National University, Mount Stromlo Observatory, via Cotter Road, Weston Creek,ACT,2611, Australia
[6] Università di Padova, Dipartimento di Astronomia, Vicolo dell'Osservatorio 2, Padova,35122, Italy
[7] Instituto de Astrofísica, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Macul,Santiago,782-0436, Chile
[8] Millennium Institute of Astrophysics, Av. Vicuña Mackenna 4860, Macul,Santiago,782-0436, Chile
[9] Museo Interactivo Mirador, Dirección de Educación, Av. Punta Arenas, La Granja,Santiago,6711, Chile