Skip to main content
Circulars over Kafka event name backfill. See news and announcements

GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

8 results found.

  1. GRB 130606B: Suzaku WAM observation of the prompt emission
  2. GRB 130606B: Swift/UVOT Upper Limit
  3. GRB 130606B: AGILE-MCAL observation
  4. GRB 130606B: RATIR Optical and NIR Observations
  5. GRB 130606B: Swift-XRT observations
  6. Konus-Wind observation of GRB 130606B
  7. GRB 130606B; Fermi GBM observation
  8. GRB 130606B: Fermi-LAT detection of a bright hard burst

Advanced

Download all Circulars as a .tar.gz archive:
Looking for U.S. government information and services? Visit USA.gov