TITLE: GCN CIRCULAR NUMBER: 2159 SUBJECT: IPN triangulation of GRB030421 (annulus) DATE: 03/04/21 18:40:11 GMT FROM: Kevin Hurley at UCBerkeley/SSL K. Hurley and T. Cline, on behalf of the Ulysses GRB team, and A. von Kienlin, G. Lichti, and A. Rau, on behalf of the INTEGRAL SPI-ACS GRB team, report: Ulysses and INTEGRAL (SPI-ACS) observed this burst at 02192 seconds. As observed by Ulysses, it had a duration of approximately 170 seconds, a 25-100 keV fluence of approximately 1.3E-05 erg/cm2, and a peak flux of approximately 1.6E-06 erg/cm2 s over 0.25 seconds. We have triangulated it to a preliminary annulus centered at RA, Decl(2000)= 333.729, -38.892 degrees, whose radius is 51.349 +/- 0.018 degrees (3 sigma ). This annulus may be constrained and/or improved, but as the event was not observed by Mars Odyssey, a small error box cannot be derived for it.