skip to content

GCN: The Gamma-ray Coordinates Network (TAN: Transient Astronomy Network)

UPDATE: The only outage was from 16:05 to 18:54 UT (2.82 hrs duration).

ORIGINAL ANNOUNCEMENT: There will be intermitant interruptions in the internet connectivity with GCN this Sat, Sep 24 14:00-20:00 UT.
The network for several buildings (including the one that houses GCN) is undergoing upgrades.
There will be several outages with durations of minutes to maybe an hour.
Socket connections will drop for each interruption, and
email-based distributions will experience delayed delivery until internet access is re-established.

The GCN system distributes:
  1. Locations of GRBs and other Transients (the Notices) detected by spacecraft (most in real-time while the burst is still bursting and others are that delayed due to telemetry down-link delays).
  2. Reports of follow-up observations (the Circulars and the Reports) made by ground-based and space-based optical, radio, x-ray, TeV, and other particle observers.
These two functions provide a one-stop shopping network for follow-up sites and GRB and transient researchers.

The GCN system can be explored using the links above and below.

Invitation to subscribe to the GCN/TAN (Notices or Circulars) here.
Make a modification to an existing site configuration here.
Invitation to producers to incorporate your events into GCN here.

System Status
System Status: Latest update: 24 Sep 2016 (UT)
What's New
What's New: Latest update: 11 Sep 2016 (UT)

thumbnail of GCN physical network
The physical GCN network. (Click to enlarge.)

Latest Gamma-Ray Bursts

GCN Circulars Archive     Circs by Burst
GCN Reports Archive

The GCN/TAN contact is: Scott Barthelmy,, (301)-286-3106
(or if the Goddard email is down).

A service of the Astrophysics Science Division (ASD) at NASA's GSFC.

  • Astronomy Questions? Ask a High Energy Astronomer.
  • NASA-specific Questions? Try the NASA Homepage or start at the NASA site map.
  • Curator: Teresa Sheets
  • Responsible NASA Official: Phil Newman
    NASA Privacy Statement, Disclaimer, and Accessibility Certification
    This file was last modified on Sunday, 25-Sep-2016 09:38:21 EDT