Skip to main content
Circulars over Kafka event name backfill. 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"

610 results found.

  1. SGR1806: Detection of a Sudden Ionospheric Disturbance
  2. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  3. VLA observations of SGR 1806-20
  4. SGR1806 VLA Observations
  5. VLA observations of SGR 1806-20
  6. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  7. Detection of the SGR 1806-20 giant outburst back-scattered by the
  8. The giant outburst from SGR 1806-20
  9. Giant flare from SGR 1806-20 detected by INTEGRAL
  10. Very high activity of SGR 1806-20
  11. Summary of the recent bursts from SGR 1806-20
  12. IBAS GRB Alert # 2034
  13. Bright bursts from SGR1806-20
  14. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  15. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  16. Very strong outburst from SGR 1806-20 detected with INTEGRAL
  17. SGR 1806-20 still active
  18. An intense burst from SGR1806-20
  19. Very bright burst detected from SGR 1806-20
  20. Increase of SGR 1806-20 activity
  21. Bursting activity from SGR 1806-20 detected with IBAS
  22. Ongoing activity of SGR 1806-20
  23. GRB040706:observation at University of Miyazaki
  24. SGR 1806-20: no IR variability of the proposed counterparts
  25. SGR 1806-20, potential NIR counterpart
  26. Activivty of SGR 1806-20
  27. IBAS GRB Alerts n.1785 to 1791
  28. Summary of recent bursts from SGR 1806-20 detected by INTEGRAL
  29. IBAS GRB Alert 1694
  30. IBAS GRB alerts 1679, 1680, 1681
  31. IBAS results on a burst from SGR1806-20
  32. IBAS alert 1180 refers to a burst from SGR 1806-20
  33. Ongoing Bursting Activity from SGR 1806-20 detected with IBAS
  34. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  35. SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
  36. A burst from SGR 1806-20 detected with IBAS
  37. IPN triangulation of GRB030926 (short/hard; large error box)
  38. IBAS detection of bursts from SGR 1806-20
  39. Radio Observations of SGR1806-20
  40. INTEGRAL ToO OBSERVATIONS OF SGR1806-20: CALL FOR CORRELATED OBSERVATIONS
  41. Summary of recent IPN and HETE detections of SGR bursts
  42. Clarification of GCN 2354 on SGR1806-20
  43. IPN detection of continued activity from SGR1806-20
  44. 030813 SGR event (Konus-Wind observation)
  45. SGR 1808-20 (=H2802): A Possible new SGR
  46. SGR 1806-20, submm observations
  47. RXTE PCA Observations of SGR1806-20 Region
  48. HETE detection of burst from SGR1806-20
  49. GRB030329 observed as a sudden ionospheric disturbance (SID)
  50. IPN triangulation of GRB021219
  51. IPN detection of continued activity from SGR1806-20
  52. IPN detection of renewed activity from SGR1806-20
  53. IPN detection of continued SGR1900+14 activity
  54. IPN confirmation of the reactivation of SGR1900+14
  55. IPN detection of possible reactivation of SGR1900+14
  56. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  57. SGR1900+14 activity, November 2-4, 2002
  58. Detection of activity from SGR 1900+14 with the RXTE/PCA
  59. GRB 021008, optical observations
  60. IPN triangulation of GRB021008 (single error box)
  61. IPN triangulation of GRB021008 (two small error boxes)
  62. IPN detection of a burst from SGR1900+14
  63. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  64. SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up
  65. AXP 1E2259+586: quasi-simultaneous optical observation
  66. AXP 1E2259+586 optical observations
  67. SGR-like Bursts from the AXP 1E 2259+586
  68. IPN detection of possible bursts from SGR1806-20
  69. XRF 020427: Sudden Ionospheric Disturbance (SID)
  70. Mars Odyssey joins the IPN
  71. IPN detection and localization of Cygnus X-1 flares
  72. RXTE Observations of SGR 1900+14
  73. SGR1900+14 activity
  74. IPN/HETE Detection of Bursts from SGR1900+14
  75. IPN detection of further activity from SGR1806-20
  76. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  77. Probable SGR or Short Duration GRB Detected by HETE
  78. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  79. Possible burst from SGR1806-20
  80. IPN detection of SGR1900+14
  81. X-ray precursors to the large flare from SGR 1900+14
  82. SGR 1900+14: No evidence of extended X-ray emission
  83. SGR 1900+14 : RXTE observations
  84. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  85. SGR1900+14
  86. SGR 1900+14: Correction to GCN 1049
  87. Millimeter observation of SGR 1900+14
  88. SGR 1900+14: Detection of extended X-ray emission
  89. Chandra Observations of SGR 1900+14
  90. SGR 1900+14, Chandra observations
  91. Chandra Observations of SGR 1900+14
  92. SGR1900+14, I-band observations
  93. SGR 1806-20 burst activity
  94. BATSE GRB trigger criteria
  95. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  96. GRB990308 not a new SGR
  97. GRB990308, Possible new SGR~0209+70
  98. SGR1900+14, BeppoSAX-GRBM observations
  99. SGR1627-41
  100. SGR1627-41, RXTE/ASM 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