A&A 472, 311–319 (2007) Astronomy DOI: 10.1051/0004-6361:20066927 & c ESO 2007 Astrophysics Light curves and colours of the faint Uranian irregular satellites Sycorax, Prospero, Stephano, Setebos, and Trinculo, M. Maris1, G. Carraro2,3, and M. G. Parisi4,5,6 1 INAF – Osservatorio Astronomico di Trieste, via G.B. Tiepolo 11, 34131 Trieste, Italy e-mail:
[email protected] 2 Dipartimento di Astronomia, Università di Padova, Vicolo Osservatorio 2, 35122 Padova, Italy e-mail:
[email protected] 3 Andes Prize Fellow, Universidad de Chile and Yale University 4 Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago, Chile e-mail:
[email protected] 5 Member of the Centro de Astrofisica, Fondo de Investigacion Avanzado en Areas Prioritarias (FONDAP), Chile 6 Member of the Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET), Argentina Received 13 December 2006 / Accepted 17 April 2007 ABSTRACT Context. After the work of Gladman et al. (1998, Nature, 392, 897), it is now assessed that many irregular satellites are orbiting around Uranus. Aims. Despite many studies performed in past years, very little is know about the light-curves of these objects and inconsistencies are present between colours derived by different authors. This situation motivated our effort to improve both the knowledge of colours and light curves. Methods. We present and discuss, the time series observations of Sycorax, Prospero, Stephano, Setebos, and Trinculo, five faint, irregular satellites of Uranus, which were carried out at VLT, ESO Paranal (Chile) on the nights between 29 and 30 July, 2005 and 25 and 30 November, 2005.