Skip to main content
Due to the lapse in federal government funding, NASA is not updating this website. See the Operations FAQ for GCN impacts.
New! Super-Kamiokande JSON Notices and Schema v4.5.0. 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"

25743 results found.

  1. GRB980519 BATSE Observations
  2. GRB980519 Optical Observations
  3. GRB980519 Optical Observations
  4. GRB 980519 Optical Observations
  5. GRB980515, BeppoSAX IAUC to be submitted
  6. BSAX Observations of GRB980425 field
  7. IPN web site of GRBs
  8. GRB980425 BATSE observations
  9. SAX J0840.7+2248 Optical Observations
  10. GRB980425: optical obs.
  11. GRB980425: Radio Observations
  12. report on BSAX observations of GRB980425
  13. GRB 980329 ROSAT observation
  14. GRB980326 X-ray Observations
  15. GRB980326, optical observations
  16. GRB980326, optical observations
  17. GRB980329, Fading IR counterpart to radio source
  18. GRB980329 Keck K-band observations
  19. GRB980329 sub-millimeter observations
  20. GRB980329 optical observations
  21. GRB980329 near-IR observations
  22. GRB980329 near-IR observations
  23. GRB980326 optical observations
  24. GRB980329 optical observations
  25. GRB980329 VLA observations
  26. GRB980329 optical observations
  27. GRB980329 optical observations
  28. GRB980326 optical observations
  29. GRB980326 optical observations
  30. Optical Observations of GRB 970508
  31. Near-IR follow-up on GRB 971227
  32. Optical Observations of the GRB 971227 field
  33. Optical Observations on GRB 971227
  34. GRB971227: Plaskett R-band observations
  35. GRB 971227: Optical clarifications
  36. GRB971227: Further CAHA R-band images
  37. GRB971227: LOTIS observations
  38. GRB971214: Optical Observations and Calibrations
  39. GRB 971214: Optical Observations
  40. Radio Observations of GRB 971214 at the VLA
  41. GRB 971024: Refined analysis by USNOFS Observations
  42. GRB 971024: KPNO Optical Observations
  43. 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