TITLE: GCN CIRCULAR NUMBER: 44589 SUBJECT: GRB 260510C: Infrared J and Hs detections with MDM/MIRAGE DATE: 26/05/12 20:44:36 GMT FROM: Geoffrey Mo at Caltech / Carnegie Observatories <gmo@mit.edu> Geoffrey Mo (Carnegie/Caltech), K. De, V. Karambelkar, S. Ibrahim, D. Schiminovich (Columbia University) report: We observed the field of GRB 260510C (Fermi GBM Team, GCN 44520; Gotz et al., GCN 44521; Iwakiri et al., GCN 44526; Fu et al., GCN 44541; Arya et al., GCN 44544; Palafox et al., GCN 44564) in the near-infrared J and Hs bands with the MDM InfraRed Astronomy inGaas Explorer (MIRAGE) instrument on the MDM 1.3 m telescope. Observations began at 2026-05-11T03:31:14 (+10.3 hours after the GRB trigger) in the J band and 2026-05-11T04:04:31 (+10.8 hours) in the Hs band, lasting 1620 s in each filter. The optical counterpart (Li et al, GCN 44527; Angulo et al., GCN 44530; Li et al., GCN 44540; Lee et al., GCN 44570) is detected in both filters, with the following AB magnitudes: J = 19.64 ± 0.16, Hs = 19.42 ± 0.24. MIRAGE is a new YJHs-band near-infrared imager for the MDM 1.3m telescope. We thank the MDM Observatory staff for supporting the observations. View this GCN Circular online at https://gcn.nasa.gov/circulars/44589. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...