Skip to main content
New! Browse Circulars by Event, Advanced Search, Sample Codes, Schema Release. 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"

29 results found.

  1. GRB 100906A: optical observations
  2. GRB 100906A: D50 optical detection
  3. GRB 100901A: errata of GRB name in GCN 11270
  4. GRB 100901A: optical observations in Mondy and R-light curve
  5. GRB 100906A: optical observations at Mt.Terskol
  6. GRB100906A: detection at 15GHz
  7. GRB 100906A: RTT150 optical observations
  8. GRB 100906A: GRAS-007 optical observations
  9. GRB100906A: R band observations
  10. Konus-Wind observation of GRB 100906A
  11. GRB100906A: non-detection at 15GHz
  12. GRB100906A: Optical observations at IAO
  13. GRB 100906A: Fermi GBM observation
  14. GRB 100906A: TLS Monitoring
  15. GRB 100906A: Observations at the Virtual Telescope
  16. GRB 100906A: Swift-XRT refined analysis
  17. GRB 100906A: Enhanced Swift-XRT position
  18. GRB 100906A: Swift/UVOT Observations
  19. GRB100906A: MITSuME Okayama Optical Observation
  20. GRB 100906A: Ondrejov 65cm observations
  21. GRB 100906A: TLS Multicolor Observations
  22. GRB 100906A: MASTER preliminary prompt+afterglow lc
  23. GRB 100906A: Swift-BAT refined analysis
  24. GRB 100906A: UKIRT zYJHK Observation
  25. GRB 100906A: MASTER preliminary polarization prompt light curve
  26. GRB 100906A: Gemini-N/GMOS redshift
  27. GRB 100906A : Faulkes Telescope North optical observations
  28. GRB 100906A: MASTER early OT observations
  29. GRB 100906A: Swift detection of a burst with an optical afterglow

Advanced

Download all Circulars as a .tar.gz archive:
Questions or comments?
Contact GCN directly.
Have you found a bug in GCN?
Open an issue.
Want to contribute code to GCN?
Get involved on GitHub.

gcn.nasa.gov

A service of the Astrophysics Science Division at NASA Goddard Space Flight Center

Looking for U.S. government information and services? Visit USA.gov