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GCN: NASA's Time-Domain and Multimessenger Alert System

GCN distributes alerts between space- and ground-based observatories, physics experiments, and thousands of astronomers around the world.

GCN diagram

The General Coordinates Network (GCN) is a public collaboration platform run by NASA for the astronomy research community to share alerts and rapid communications about high-energy, multimessenger, and transient phenomena. For more information, see What is GCN? or check out our slide deck.

There are three ways to stream GCN Notices in real time:

Why switch from GCN Classic to Kafka?

GCN ClassicGCN Classic over Kafka
NO. Users need to contact administrator in order to make account and subscription changesYES. Manage your own account and subscription settings through this web site
Open standards
NO. Notices are sent using three custom protocolsYES. Notices are sent using one standard protocol, Apache Kafka
Open source
NO. Custom software needed to receive noticesYES. Receive notices using open-source software
Highly available
NO. Notices are broadcast by a single serverYES. Notices are broadcast by a cluster of highly-available Kafka brokers in the cloud
NO. Notices are sent as plaintextYES. Notices are protected with SSL/TLS

Honors and Awards

Coming Soon

The GCN Viewer is an interactive, searchable, filterable index of all GCN Notices and Circulars, updated in real time. In the near future, it will be integrated with this web site.

See the GCN Road Map for more features that are coming soon to GCN.

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