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

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 here.

System Status
System Status: Latest update: 28 Apr 2015 (UT)
What's New
What's New: Latest update: 24 Nov 2015 (UT)

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

Latest Gamma-Ray Bursts

GCN Circulars Archive
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.

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  • Curator: Teresa Sheets
  • Responsible NASA Official: Phil Newman
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    This file was last modified on Tuesday, 24-Nov-2015 11:29:35 EST