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

Posted 30 Aug 2020:
One of the GCN VOevent servers ( was, down from ~12:10 to ~12:20UT.

Posted 31 Jul 2020:
The ICECUBE_CASCADE notice type was added to GCN.

Posted 23 Mar 2020 (updated 27 Mar 2020, 04 Apr 2020, 03 May 2020, 08 May 2020; still going 10 Aug 2020):
Due to the policies and constraints during the CoronaVirus pandemic,
my response to your requests and questions may not be as fast as normal.
Example: changes to your site_configuration may take several days
of having to use a remote access connection (all Goddard personnel must tele-work from home).
For "essential personnel" the access time is still 24/7, but the duration is only ~4 hrs/week.

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) 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 Notices or Circulars here.    unsubscribe here.
Make a modification to an existing Notices site configuration here.
Invitation to producers to incorporate your events into GCN here.

System Status
System Status: Latest update: 27 Jul 2020 (UT)
What's New
What's New: Latest update: 31 Jul 2020 (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 HEASARC at the Astrophysics Science Division (ASD) at NASA's GSFC.

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  • Curator: Teresa Sheets
  • Responsible NASA Official: Phil Newman
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    This file was last modified on Sunday, 30-Aug-2020 12:23:03 EDT