Skip to main content
New! BOOM Notices and Schema v7.0.0. 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').
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"

35152 results found.

  1. GRB 000115 Optical observations
  2. GRB 000214, Radio Observations
  3. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  4. GRB 000115, BVRI field photometry
  5. IPN annulus for GRB000214
  6. BATSE GRB trigger criterion changed
  7. GRB000210 X-ray afterglow
  8. GRB000214: X-ray afterglow candidate
  9. BeppoSAX GRB000214 ("S. Valentine's day GRB")
  10. GRB 000210: BATSE Observations
  11. Optical observations of the Chandra X-ray source for GRB000210
  12. Chandra Observations of GRB000210 X-ray Afterglow
  13. IPN triangulation of GRB000210
  14. GRB 000201: TAROT optical observations
  15. GRB 000131 Optical Observations
  16. GRB000126 Optical Observations
  17. BATSE GRB trigger criteria changed
  18. GRB 991208, radio observations
  19. BATSE+IPN location of GRB000131
  20. IPN localization of GRB000131
  21. GRB 000126, optical observations
  22. GRB000126, optical observations
  23. BATSE location of GRB000126
  24. IPN localization of GRB000126
  25. GRB 000115 Optical observations
  26. BATSE Observations of GRB000115
  27. Second RXTE Observation of GRB 000115
  28. GRB991216, UBVRIJHK field photometry
  29. Single IPN error box for GRB991229
  30. GRB 991216 VLBA Observations
  31. BEPPOSAX GRBM Localization of GRB991226
  32. IPN error boxes for GRB991229
  33. GRB 991216: J band spectrophotometry
  34. GRB 991216: Detection of the Host and/or Absorber Galaxy
  35. IPN localization of GRB991226
  36. Single IPN error box for GRB991221
  37. IPN error boxes for GRB991221
  38. GRB 991216 RXTE ASM Observations
  39. IPN error box for GRB991216
  40. GRB 991216: Updated BATSE parameters
  41. Lowell/Perkins observation of GRB 991216
  42. GRB 991217 (SAX J2303.2+0015) Optical observations
  43. Chandra observation of the X-ray afterglow of GRB991216
  44. GRB 991216, optical observations
  45. GRB 991216 Optical Observations
  46. GRB 991216 Optical spectroscopy/imaging
  47. K observations of GRB991216
  48. GRB 991217 (SAX J2303.2+0015) Optical observations
  49. GRB991216 Spectroscopy
  50. Lowell/Perkins observation of GRB 991216
  51. GRB991216, optical observations
  52. Refined IPN localization of GRB991216
  53. GRB 991216 Radio Observations
  54. GRB 991217
  55. GRB 991208 Keck Spectroscopy
  56. GRB 991208 Infrared Detection
  57. GRB 991216--Summary of RXTE Observations
  58. GRB 991216 Optical Observations
  59. GRB 991216, optical observations
  60. GRB 991208 SAO-RAS Spectroscopy
  61. SAX J2303.2+0015: an x-ray/GRB?
  62. GRB 991216, Optical Transient
  63. GRB 991216, Optical Afterglow
  64. GRB 991216: Comparison with DPOSS images
  65. GRB 991208 optical observations
  66. Lowell/Perkins observation of GRB 991216
  67. GRB 991216 Optical Observation
  68. GRB 991208 Keck Spectroscopy
  69. GRB 991216: Extremely bright BATSE burst
  70. GRB991208, optical observations
  71. GRB 991208 Keck Spectroscopy
  72. GRB991208 - millimeter detection
  73. GRB 991208, Optical Observation
  74. GRB 991208 - OVRO detection
  75. GRB 991208 Optical Decay
  76. GRB 991208 optical observations
  77. GRB 991208 optical observations
  78. GRB 991208: Radio Observations
  79. IPN localization of GRB991208
  80. Optical Observations of GRB991105
  81. GRB991106: BeppoSAX/BATSE results
  82. GRB 991106, optical observations
  83. GRB991106, near-infrared observations
  84. BeppoSAX NFI Observation of GRB991106
  85. GRB 991106, radio observations
  86. GRB991106: the first BeppoSAX short GRB detection?
  87. GRB 991105: BATSE Observations
  88. IPN localization of GRB991105
  89. GRB 991106 Optical Observations
  90. GRB 991105, optical observations
  91. GRB991106, optical observation at SAO-RAS
  92. GRB 991106, LOTIS Optical Observations
  93. GRB 991106, optical observations
  94. BeppoSAX GRB Alert: GRB991106
  95. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  96. GRB ALERT: GRB991105
  97. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  98. GRB 991014, Optical Observations
  99. GRB 991014 - BeppoSAX NFI observations
  100. GRB 991014, Optical 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