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"

24605 results found.

  1. GRB000301C
  2. GRB 000301C : Optical Candidate
  3. GRB000301C: RXTE/ASM and IPN localizations
  4. GRB000226 [IPN Position]
  5. HST Observations of GRB 990712
  6. GRB 000214 near-IR observations
  7. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  8. GRB000210, Radio Observations
  9. GRB 000115, BVRI field photometry
  10. GRB000214: BeppoSAX GRBM and WFC Detection
  11. Optical observations of GRB000210
  12. GRB000210 X-ray afterglow
  13. GRB000214: X-ray afterglow candidate
  14. GRB000214 refined BeppoSAX-WFC position
  15. GRB 000210: BATSE Observations
  16. Optical observations of the Chandra X-ray source for GRB000210
  17. GRB000210, Radio Observations
  18. IPN triangulation of GRB000210
  19. GRB000210: possible afterglow detection with BeppoSAX NFI
  20. GRB000201, Radio Observations
  21. GRB000210: BeppoSAX GRBM and WFC Detection
  22. SAX_WFC_GRB_NOTICE
  23. SAX_WFC_GRB_NOTICE
  24. GRB000201 Optical Observations
  25. GRB 000201: TAROT optical observations
  26. GRB 991208, radio observations
  27. BATSE+IPN location of GRB000131
  28. IPN localization of GRB000131
  29. GRB 000126, optical observations
  30. BATSE Observations of GRB000115
  31. Second RXTE Observation of GRB 000115
  32. GRB991216, UBVRIJHK field photometry
  33. GCN resumes full operations
  34. GRB 991216 VLBA Observations
  35. GRB 991216: J band spectrophotometry
  36. GRB 991216: Detection of the Host and/or Absorber Galaxy
  37. IPN localization of GRB991226
  38. GRB 991216 RXTE ASM Observations
  39. GRB 991216: Updated BATSE parameters
  40. GRB 991217 (SAX J2303.2+0015) Optical observations
  41. Chandra observation of the X-ray afterglow of GRB991216
  42. GRB 991216, optical observations
  43. GRB 991216 Optical spectroscopy/imaging
  44. SAX J2303.2+0015 Optical observations
  45. IR observations of GRB991216
  46. GRB 991217 (SAX J2303.2+0015) Optical observations
  47. GRB991216 Optical and infrared observations of Beethoven Burst
  48. GRB 991216 Radio Observations
  49. GRB 991208 Keck Spectroscopy
  50. GRB 991208 Infrared Detection
  51. GRB991216
  52. GRB 991216--Summary of RXTE Observations
  53. GRB 991216 Optical Observations
  54. GRB 991216, optical observations
  55. GRB 991208 SAO-RAS Spectroscopy
  56. SAX J2303.2+0015: an x-ray/GRB?
  57. GRB 991216, Optical Transient
  58. GRB991216 ('Beethoven Burst') B, R, and K Observations
  59. GRB991216, infrared observations
  60. GRB 991208 optical observations
  61. GRB 991216 Optical Observation
  62. GRB 991216: Extremely bright BATSE burst
  63. R-band Observations of GRB991208 at TNG
  64. GRB991208, optical observations
  65. GRB 991208, Optical Observation
  66. GRB991208, optical observations
  67. GRB 991208 optical observations
  68. Optical Observations of GRB991105
  69. GRB991106: BeppoSAX/BATSE results
  70. GRB991106, near-infrared observations
  71. BeppoSAX NFI Observation of GRB991106
  72. GRB 991106, radio observations
  73. GRB991106: the first BeppoSAX short GRB detection?
  74. GRB 991105: BATSE Observations
  75. GRB 991106 Optical Observations
  76. GRB991106, optical observation at SAO-RAS
  77. GRB 991106, LOTIS Optical Observations
  78. GRB991105: SAX-GRBM/-WFC detection
  79. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  80. GRB 991014, Optical Observations
  81. GRB 991014 - BeppoSAX NFI observations
  82. GRB 991014, radio observations
  83. GRB 991014, Optical Observations
  84. GRB 991014, optical observations
  85. GRB 990915 optical observations
  86. Optical Observations of GRB990907
  87. GRB990907: BeppoSAX follow up and X-ray afterglow
  88. GRB990907 and 990908
  89. GRB 990712 Late Optical Decay and Host Galaxy
  90. GRB990806 BeppoSAX follow up
  91. GRB990806: BATSE Observations
  92. GRB 990806 Optical observations
  93. GRB 990806, Optical Observations
  94. GRB 990806, optical observations
  95. GRB 990806, Optical Observations
  96. GRB990806 UBVRIJHK observations
  97. GRB 990712 Optical Observations
  98. GRB 990712
  99. Late-time HST/STIS Observations of GRB 990510
  100. BeppoSAX NFI Observation of GRB990705

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