Skip to main content
GCN at AAS 245, Legacy Circulars Address Retirement. 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').

22 results found.

  1. Konus-Wind detection of GRB 210610B
  2. uGMRT radio detection of GRB 210204A
  3. GRB 210204A (ZTF21aagwbjr/AT2021buv): continued Assy and Mondy optical observations
  4. GRB 210204A (ZTF21aagwbjr/AT2021buv): continued CrAO and AbAO optical observations
  5. GRB 210204A: observations with the 3.6m Devasthal Optical Telescope and possible jet break
  6. GRB 210204A (ZTF21aagwbjr/AT2021buv): continued Mondy optical observations
  7. GRB 210204A: LBT observations and jet break
  8. GRB 210204A: redshift revision of ZTF21aagwbjr/AT2021buv (correction to GCN 29411)
  9. Konus-Wind detection of GRB 210204A (correction to GCN 29415)
  10. GRB 210204A (ZTF21aagwbjr/AT2021buv): Mondy and AbAO optical observations
  11. Konus-Wind detection of GRB 210204A / ZTF21aagwbjr
  12. GRB 210204A: Optical Observations from HCT
  13. GRB 210204A / ZTF21aagwbjr: Swift-XRT observations
  14. GRB 210204A: Swift ToO observations
  15. VLT/X-shooter redshift of 1.466 for ZTF21aagwbjr/AT2021buv, strengthening its association with GRB 210204A
  16. GRB 210204A: AstroSat CZTI Detection
  17. IPN triangulation of GRB 210204A
  18. Fermi GRB 210204A: Global MASTER-Net observations report
  19. GRB 210204: Fermi GBM observation
  20. GRB 210204A: GECAM detection
  21. GRB 210204A: BALROG localization (Fermi Trigger 634112970 / GRB 210204270)
  22. GRB 210204A: Fermi GBM Final Real-time Localization

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