General Coordinates Network

The General Coordinates Network (GCN) is a service of NASA that promptly informs researchers about recent gamma-ray bursts and other transients (e.g., neutrino detections, GW detections) discovered by NASA's and other astronomical satellites, and by various ground-based detectors. The GCN offers both machine-readable alerts (notices) and written alerts (circulars) regarding reported transients, and provides an online archive (GCN archive) of those distributed. The service can e-mail them, and the notices can be received through an Internet connection. The reports include the transient's type, coordinates, time, and general description, along with the device and team that detected it.

The current GCN is an outgrowth of the Gamma-ray burst Coordinates Network (which also used the abbreviation, GCN), which, in turn, was an outgrowth of the BATSE coordinates distribution network (BACODINE), created to provide this function for GRB discoveries by the Compton Gamma Ray Observatory (CGRO) instrument, BATSE. BACODINE was introduced in 1993, was expanded into the Gamma-ray burst Coordinates Network in 1997, and into the current GCN in 2022.