GRB 260221B

Summary

General information

GRB 260221B triggered Fermi/GBM at 23:18:22 UT on 2026-02-21 and is described as a likely short GRB. MASTER-Kislovodsk reported optical follow-up observations starting about 9.8 ks after the trigger with only upper limits.

Wavelength coverage

Lightcurve and spectrum

Redshift

What’s special vs typical

Circulars [all]

GCN 43801: Fermi GRB 260221B: Global MASTER-Net observations report
2026-02-22T02:30:42.876Z | rev 0
GCN 43800: GRB 260221B: Fermi GBM Final Real-time Localization
2026-02-21T23:29:14.552Z | rev 0