Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! 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"

35982 results found.

  1. GRB 010222 HST/Chandra TOO
  2. GRB 010222
  3. GRB010222 further R-band photometry
  4. GRB010222: R-band data
  5. GRB010222 Optical observations
  6. GRB 010222: Keck Spectroscopy
  7. GRB010214, field photometry
  8. GRB010222, field photometry
  9. GRB010222 further R-band photometry
  10. GRB010222, possible increase of optical decay slope
  11. GRB 010222 Kyoto optical observation
  12. GRB010222: fading behavior
  13. GRB 010222 BV optical observations
  14. GRB 010220: Near-IR Observations
  15. GRB010214 follow-up from Hanle
  16. GRB 010222: Near-IR Observations
  17. GRB 010222: Optical Observations
  18. GRB 010222, Decay Slope Confirmed
  19. GRB010222: Another absorption line system
  20. GRB010222: Optical decay slope
  21. GRB 010214, Optical Observations
  22. GRB010222: Sub-millimeter detection
  23. GRB010222: R-band fading behavior
  24. GRB010222: Optical Observations
  25. GRB010222, optical observations
  26. GRB010222: BeppoSAX/NFI Observations
  27. Redshift of the Optical Transient of GRB010222
  28. GRB010214B,Gamma Ray Observations
  29. GRB010222
  30. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  31. GRB 010220, simultaneous optical observations
  32. GRB010220: BeppoSAX WFC and GRBM preliminary data
  33. BeppoSAX ALERT: GRB010220
  34. GRB010214: BeppoSAX WFC and GRBM preliminary data
  35. GRB 010214: X-Ray afterglow
  36. GRB 010214, Optical Observations
  37. GRB 010214 optical observation
  38. GRB010213 Optical Observation
  39. J-Band Observation of GRB 010214.
  40. GRB010213, Near-IR observations
  41. Possible InfraRed Transient of GRB 010214.
  42. GRB010214 Optical Observation
  43. GRB010214: BeppoSAX/NFI Observations
  44. GRB010213 (HETE) TAROT observations
  45. GRB 010214, optical observations
  46. BeppoSAX ALERT: GRB010214
  47. IPN Status Report
  48. HETE Status
  49. GRB010126 opt. obs.
  50. IPN/RXTE TRIANGULATION OF GRB010126
  51. GRB010126: CONCAM crude optical limits during GRB
  52. GRB010126, TNG R-band observations
  53. IPN TRIANGULATION OF GRB010126
  54. IPN/RXTE TRIANGULATION OF GRB010126
  55. GRB 010119, optical observations
  56. GRB010119: Optical observations
  57. Optical Observations of GRB 001018 at Keck
  58. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  59. Optical observations of GRB 001018 with JCAM
  60. IPN TRIANGULATION OF GRB010115
  61. IPN TRIANGULATION OF GRB010109
  62. GRB010103, optical observations
  63. IPN triangulation of GRB010104
  64. IPN triangulation of GRB010103
  65. GRB 001204: Ks observations
  66. H band observation of GRB 001212
  67. GRB & BeppoSAX: ground operations restored back to 24 hrs a day
  68. IPN triangulation of GRB001219
  69. GRB 001212 Optical Observation
  70. GRB 001212 Optical Observation
  71. GRB 001212 optical observation
  72. GRB 001212 possible OA in 2MASS
  73. GRB 001212 possible OA
  74. IPN triangulation of GRB001212
  75. Confirmation of IPN position for GRB001204
  76. IPN triangulation of GRB001204 (short/hard)
  77. GRB 001105, further optical observations
  78. GRB001120: Gunn-i observations
  79. GRB001120: Optical observations
  80. GRB001109, optical observations
  81. GRB001120, optical observations
  82. IPN triangulation of GRB001120
  83. Optical/NIR observations of GRB001109
  84. GRB 001109: deep JHK upper limits
  85. GRB 001109 X-ray afterglow with BeppoSAX
  86. GRB001109: Optical observations
  87. GRB001109: BeppoSAX/NFI Observations
  88. GRB001109, R-band optical observations
  89. GRB001109, Radio observations
  90. BeppoSAX ALERT: GRB001109
  91. GRB001105 BVRI field photometry correction
  92. GRB001105, BVRI field photometry
  93. GRB 001105, R-band observation
  94. IPN TRIANGULATION OF GRB001105
  95. GRB 001025B, Optical obervations
  96. GRB 991208: HST Imaging of the Host Galaxy
  97. GRB000926: R-image of the host galaxy
  98. GRB 001025B, I-band observations
  99. GRB 001025 Optical Observations
  100. GRB 001025A, optical observation

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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