Skip to main content
Introducing Einstein Probe, Astro Flavored Markdown, and Notices Schema v4.0.0. 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').

24 results found.

  1. GRB 090709A: Host galaxy detection
  2. GRB 090709A : Quick look analysis of the Suzaku observation
  3. GRB 090709A: Swift XRT Timing Analysis
  4. GRB 090709A - CARMA mm Observations
  5. GRB 090709A: Xinglong TNT optical upper limit
  6. VLA radio observations of GRB 090709A
  7. GRB 090709A: deep optical observation with the 10.4m GTC
  8. GRB 090709A: Suzaku WAM observation of the prompt emission
  9. GRB 090709A: Swift UVOT upper limits
  10. GRB 090709A: WHT LIRIS observations
  11. GRB 090709A: confirmation of the periodicity in the SPI-ACS data
  12. GRB 090709A: evidence for a very red afterglow at low z
  13. Konus-Wind and Konus-RF observations of GRB 090709A
  14. GRB 090709A: P60 Observations
  15. GRB 090709A: Quasiperiodic variations in the BAT light curve
  16. GRB 090709A: NOT optical observations
  17. GRB 090709A: RAPTOR Limits During Gamma-Ray Emission
  18. GRB 090709A: Swift XRT Refined Analysis
  19. GRB 090709A: Swift-BAT refined analysis
  20. GRB 090709A: Wyoming Infrared Observatory NIR upper limits
  21. GRB 090709A, RIMOTS optical upper limits
  22. GRB 090709A: Enhanced Swift-XRT position
  23. GRB 090709A - PAIRITEL Discovery of a Red Afterglow
  24. GRB 090709A: Subaru NIR observation


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