Skip to main content
Updated Client Credential Expiration Policy. 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"

17642 results found.

  1. Discovery of a new SGR source, SGR1627-41
  2. GRB980613 Optical Observations
  3. GRB980613 observations from Palomar
  4. GRB980613 Near Infra-Red Observations
  5. GRB971214 Secondary Standards
  6. GRB980519 Secondary Standards
  7. GRB 980519 Optical Observations
  8. GRB 980519
  9. GRB980519 optical observations
  10. GRB 980519 Optical Observations
  11. GRB980519 Optical Observations
  12. GRB 980519 Optical Observations
  13. GRB980515, BeppoSAX IAUC to be submitted
  14. BSAX Observations of GRB980425 field
  15. SAX J0840.7+2248 Optical Observations
  16. GRB980425: optical obs.
  17. GRB980425: Radio Observations
  18. report on BSAX observations of GRB980425
  19. GRB980326 X-ray Observations
  20. GRB980326, optical observations
  21. GRB980326, optical observations
  22. GRB980326 IPN annulus
  23. GRB980329 Keck K-band observations
  24. GRB980326 optical observations
  25. GRB980329 optical observations
  26. GRB980329 VLA observations
  27. GRB980329 optical observations
  28. GRB980326 optical observations
  29. Optical Observations of GRB 970508
  30. Near-IR follow-up on GRB 971227
  31. Optical Observations of the GRB 971227 field
  32. Optical Observations on GRB 971227
  33. GRB971227: Plaskett R-band observations
  34. GRB 971227: Optical clarifications
  35. GRB971227: Further CAHA R-band images
  36. GRB971227: LOTIS observations
  37. GRB 971227: CAHA R-band images
  38. GRB971214: Optical Observations and Calibrations
  39. GRB 971214: Optical Observations
  40. Radio Observations of GRB 971214 at the VLA
  41. GRB 971024: KPNO Optical Observations
  42. GRB 970828: Palomar Observations

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