TITLE: GCN GRB OBSERVATION REPORT NUMBER: 509 SUBJECT: IPN localization of GRB991226 DATE: 99/12/27 23:33:55 GMT FROM: Kevin Hurley at UCBerkeley/SSL K. Hurley, on behalf of the Ulysses GRB team, M. Feroci, on behalf of the BeppoSAX GRB team, and T. Cline, on behalf of the NEAR GRB team, report: Ulysses, the BeppoSAX GRBM, and NEAR observed a ~25 s long burst whose 25-100 keV fluence was ~2 x 10^-6 erg/cm^2 on December 26, 1999 at 14:59:57 UT. We have triangulated this burst to two possible ~70 sq. arcmin. error boxes, whose coordinates are given below. Further examination of the BeppoSAX data should allow us to determine which of the intersections the burst originates from. RA(2000) DEC(2000) 14 h 38 m 50.18 s -61 o 26 ' 9.81 " 14 h 38 m 17.77 s -61 o 41 ' 15.52 " 14 h 38 m 36.73 s -61 o 14 ' 11.84 " 14 h 38 m 4.71 s -61 o 29 ' 22.01 " OR RA(2000) DEC(2000) 13 h 14 m 42.16 s -1 o 46 ' 50.68 " 13 h 13 m 54.72 s -1 o 36 ' 44.08 " 13 h 15 m 4.53 s -1 o 57 ' 32.89 " 13 h 14 m 17.01 s -1 o 47 ' 21.34 "