TITLE: GCN CIRCULAR NUMBER: 29983 SUBJECT: Swift trigger 1047857 is 4U 1700-377 DATE: 21/05/10 20:44:22 GMT FROM: Kim Page at U.of Leicester N. J. Klingler (PSU), S. Laha (GSFC/UMBC/CRESST), K. L. Page (U Leicester) and A. Tohuvavohu (U Toronto) report on behalf of the Neil Gehrels Swift Observatory Team: BAT triggered on a known source 4U 1700-377 on 2021 May 10. The precise trigger time and further analysis will be announced in a future GCN when we receive further data from the spacecraft. Swift-BAT has previously triggered on this high-mass X-ray binary, with the most recent trigger occurring on 2016 October 22.