TITLE: GCN CIRCULAR NUMBER: 8376 SUBJECT: Trigger 331721 Due to Swift startracker loss-of-lock DATE: 08/10/15 10:45:09 GMT FROM: David Palmer at LANL P. A. Evans (U Leicester), O. Godet (U Leicester), S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU), H. A. Krimm (CRESST/GSFC/USRA), N. P. M. Kuin (MSSL), J. Mao (INAF-OAB), P. T. O'Brien (U Leicester), K. L. Page (U Leicester), D. M. Palmer (LANL), P. Romano (INAF-IASFPA), M. Stamatikos (NASA/ORAU), E. Troja (INAF-IASFPA) and T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team: At ~9:50 UT on 2008-10-15 the Swift star tracker lost lock. As a result, a subsequent pointing could not correctly identify a source in the the Field of View causing a spurious BAT trigger (#331721). This is not a GRB. Recovery operations are underway.