TITLE: GCN CIRCULAR NUMBER: 42066 SUBJECT: GRB 251002A: BOOTES-6 early optical detection DATE: 25/10/02 23:27:43 GMT FROM: I. Perez-Garcia at Institute of Astrophysics of Andalusia <ipg@iaa.es> I. Perez-Garcia, S.-Y. Wu, E. Fernandez-Garcia, M.D. Caballero-Garcia, R. Sanchez-Ramirez, S. Guziy and A. J. Castro-Tirado (IAA-CSIC, Granada), P. J. Meintjes and H. J. van Heerden (UFS, South Africa), A. Martin-Carrillo and L. Hanlon (UCD, Ireland), M. Gritsevich (Univ. of Helsinki) and C. J. Perez del Pulgar (UMA, Malaga), on behalf of a larger collaboration, report: Following the detection of GRB 251002A by SVOM (Saccardi et al., GCN 42060), the BOOTES-6/DPRT 0.6m robotic telescope at Boyden Observatory in Maselspoort (South Africa) responded to this high-energy event starting on Oct 2, 20:17:55 UT (i.e., 186 sec after detection). Series of images in clear filter were gathered and we detect an optical source consistent with the one reported by Palmerio et al. (GCN 42061), Turpin et al. (GCN 42062), Jelinek et al. (GCN 42063), Juliá-Maroto et al. (GCN 42064) and Moskvitin et al. (GCN 42065). Using GaiaDR3 Gmag as reference we report our photometry analysis: | UT mid exposure | mag | error | filter | exposure time (sec) | | ------------------- | ----- | ----- | ------ | ------------------- | | 2025-10-02 20:18:25 | 15.47 | 0.03 | clear | 60 | | 2025-10-02 20:19:53 | 15.79 | 0.03 | clear | 60 | | 2025-10-02 20:21:21 | 16.16 | 0.05 | clear | 60 | Further analysis of the additional images is ongoing. We thank the staff at Boyden Observatory for their excellent support. View this GCN Circular online at https://gcn.nasa.gov/circulars/42066. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...