The Oscillation Project with Emulsion-tRacking Apparatus (OPERA) is a scientific experiment for detecting tau neutrinos from muon neutrino oscillations. The experiment is a joint effort between the European Centre for Nuclear Research (CERN) and the Gran Sasso National Laboratory (LNGS). In September 2011, OPERA scientists said that they had seen neutrinos appear to travel faster than the speed of light. However, the scientists later found problems in their equipment which had caused the anomaly. The neutrino time of flight was consistent with the speed of light.