Skip to main content
New Announcement Feature, Code of Conduct, Circular Revisions. 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').

10 results found.

  1. GRB 210626A: Swift/XRT afterglow confirmation
  2. GRB 210626A: Fermi GBM observation
  3. GRB 210626A: CAHA 2.2m telescope optical limit
  4. GRB 210626A: Ondrejov D50 optical limit
  5. GRB 210626A: GIT optical upper limit
  6. GRB 210626A: Swift-XRT afterglow detection
  7. Fermi GRB 210626A: Global MASTER-Net observations report
  8. GRB 210626A: Swift ToO observations
  9. GRB 210626A: Swift/BAT-GUANO detection and arcminute localization
  10. GRB 210626A: Fermi GBM Final Real-time Localization

Advanced

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