skip to content

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

Posted 06 Oct 2019.

GCN VOEvent cloud-computer will be taken off-line at 15:00 UT (Tue, Oct 15, 2019) (11:00 EDT)
to upgrade the system (increased memory and disk space). The upgrade will take 15-20 minutes.
This upgrade will be done to 3 of the 9 GCN VOEvent server streams (the other 6 streams already have the bigger memories & disks).
This cloud computer was the first server in the GCN cloud. The 3 streams involved in the upgrade are:  ports:   8099 (public, version 1.1),   8092 (private, ver 1.1),  &  8096 (private, ver 2.0).

In the cluster of GCN VOEvent servers, the redundant servers are
(pick the server that matches (a) your public-vs-private and (b) version number of your VOEvents you currently receive):    : port 8099, public,     version 1.1,   vetted & anonymous;  : port 8092, private,   version 1.1,   vetted only;    : port 8096, private,   version 2.0,   vetted only;  : port 8096, private,   version 2.0,   vetted only.
to which all vetted and anonymous sites can switch to if you can not tolerate a 15-20 min loss in coverage or
if the upgrade would end up taking longer than predicted.

After the end of the upgrade session (~15:20UT), please check this webpage for the status of the upgrade.

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 2019 (UT)
What's New
What's New: Latest update: 29 Aug 2019 (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.

  • 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 Monday, 14-Oct-2019 07:54:18 EDT