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

The voevent cloud server atlantic was down from 10:45 UT to 16:32 UT Sep 12, 2021 (down-time was 5.47 hrs)
due to network connection problems. The other 8 voevent cloud servers were fine.

Posted 23 Mar 2020 (last updated 18 Oct 20):
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 up to 7 days (instead of the usual 2-4 days).
Being at home teleworking, requires making the site_config file change a remote operation instead of the normal on-site operation.
Which is doable, but I try to keep that method to a minimum. I will wait longer to do the file change
or I will use a weekly 4-hr pass to do work on-site.

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: 17 Mar 2021 (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, 12-Sep-2021 13:06:16 EDT