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"

16834 results found.

  1. GRB980519 optical observations
  2. GRB 980519 Optical Observations
  3. GRB970519, optical follow-up at Schmidt Calern
  4. GRB980519 Optical Observations
  5. GRB 980519 Optical Observations
  6. GRB980515, BeppoSAX IAUC to be submitted
  7. BSAX Observations of GRB980425 field
  8. SAX J0840.7+2248 Optical Observations
  9. GRB980425: optical obs.
  10. GRB980425: Radio Observations
  11. report on BSAX observations of GRB980425
  12. GRB 980329 ROSAT observation
  13. GRB980326 X-ray Observations
  14. GRB980326, optical observations
  15. GRB980326, optical observations
  16. GRB980329 Keck K-band observations
  17. GRB980326 optical observations
  18. GRB980329 optical observations
  19. GRB980329 VLA observations
  20. GRB980329 optical observations
  21. GRB980326 optical observations
  22. Optical Observations of GRB 970508
  23. Near-IR follow-up on GRB 971227
  24. Optical Observations of the GRB 971227 field
  25. Optical Observations on GRB 971227
  26. GRB971227: Plaskett R-band observations
  27. GRB 971227: Optical clarifications
  28. GRB971227: Further CAHA R-band images
  29. GRB971227: LOTIS observations
  30. GRB971214: Optical Observations and Calibrations
  31. GRB 971214: Optical Observations
  32. Radio Observations of GRB 971214 at the VLA
  33. GRB 971024: KPNO Optical Observations
  34. 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