Skip to main content
JSON Notices via Email, Kafka Cron Jobs, Submitter Profile, GCN is Hiring. See news and announcements

GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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 181030A: Swift/UVOT Detection
  2. GRB 181030A, Swift-BAT refined analysis
  3. GRB 181030A: RATIR Optical and NIR Observations
  4. GRB 181030A: Swift-XRT refined Analysis
  5. GRB 181030A: MASTER Net OT detection
  6. GRB 181030A: Enhanced Swift-XRT position
  7. GRB 181030A: SAO RAS optical observations
  8. GRB 181030A: Swift detection of a burst with a possible optical counterpart

Advanced

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