TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1648 SUBJECT: IPN triangulation of GRB021020 DATE: 02/10/21 19:39:48 GMT FROM: Kevin Hurley at UCBerkeley/SSL K. Hurley and T. Cline, on behalf of the Ulysses, Konus, HETE, and Mars Odyssey GRB teams, I. Mitrofanov, D. Anfimov, A. Kozyrev, M. Litvak and A. Sanin, on behalf of the HEND/Odyssey GRB team, W. Boynton, C. Fellows, K. Harshman, C. Shinohara and R. Starr, on behalf of the GRS/Odyssey GRB team, E. Mazets and S. Golenetskii, on behalf of the Konus-Wind GRB team, and G. Ricker, J-L Atteia, N. Kawai, D. Lamb, S. Woosley, J. Doty, R. Vanderspek, J. Villasenor, G. Crew, G. Monnelly, N. Butler, J.G. Jernigan, A. Levine, F. Martel, E. Morgan, G. Prigozhin, J. Braga, R. Manchanda, G. Pizzichini, Y. Shirasaki, C. Graziani, M. Matsuoka, T. Tamagawa, K. Torii, T. Sakamoto, A. Yoshida, E. Fenimore, M. Galassi, T. Tavenner, T. Donaghy, M. Boer, J-F Olive, and J-P Dezalay, on behalf of the HETE GRB team, report: Ulysses, Mars Odyssey-GRS, Konus-Wind, and HETE-FREGATE (H2413) observed this GRB at 72772 seconds. As observed by Ulysses, it had a duration of approximately 20 seconds, a 25-100 keV fluence of approximately 1.1E-05 erg/cm2, and a peak flux of approximately 1.3E-06 erg/cm2 s over 0.25 seconds. We have triangulated it to a preliminary, 3 sigma error box whose approximate area is 50 sq. arcmin. and whose coordinates are: RA(2000) DEC(2000) ERROR BOX CENTER: 21 h 29 m 19.34 s 51 o 55 ' 42.00 " ERROR BOX CORNER 1: 21 h 27 m 49.13 s 51 o 47 ' 27.48 " ERROR BOX CORNER 2: 21 h 27 m 18.57 s 51 o 46 ' 27.06 " ERROR BOX CORNER 3: 21 h 31 m 22.08 s 52 o 4 ' 55.20 " ERROR BOX CORNER 4: 21 h 30 m 50.76 s 52 o 3 ' 55.67 " For technical reasons related to the transmission of the MO data, this triangulation requires confirmation, which we will attempt to provide as soon as possible. This error box may be improved.