Chilean Cardinal Jorge Arturo Medina Estevez presides over a Mass in the Vatican's St. Peter's Basilica. Chilean Cardinal Jorge Arturo Medina Estevez presides over a Mass in the Vatican's St. Peter's Basilica April 16, 2005. A conclave of 115 eligible cardinals will congregate on Monday to begin the process of electing a new pope. REUTERS/Kimimasa Mayama