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').

24545 results found.

  1. GRB060123: Optical and IR Imaging
  2. GRB 060123: P200 Observations
  3. GRB 060124: XRT refined analysis
  4. GRB 060124: R band Observations
  5. GRB 060124 : Optical observation at Xinglong and Kiso
  6. GRB060124: optical observations at Asiago
  7. GRB060123: SDSS pre-burst observations
  8. GRB 060116: Further analysis of VLT photometry and optical spectroscopy
  9. GRB 060121: OHP optical limits
  10. GRB 060124: TAROT optical limits
  11. GRB060124, optical observation
  12. GRB 060124: Optical Observations at Tautenburg
  13. GRB 060117: Suzaku WAM observation of the prompt emission
  14. GRB 060111B: Suzaku WAM observation of the prompt emission
  15. GRB 060124: Swift-BAT detection of a burst
  16. GRB 060121: Liverpool Telescopes optical limits
  17. GRB 060121: Swift XRT refined analysis
  18. Konus-Wind observation of GRB 060121
  19. GRB 060121: candidate optical counterpart
  20. GRB 060121: Infrared Observations
  21. GRB 060121: optical observations
  22. GRB 060121: Optical imaging
  23. GRB060121 - SDSS pre-burst observations
  24. HETE Alert 4006: MASTER promt optical limit
  25. GRB060117 - ATCA 3/6cm radio limits - correction
  26. GRB060117 - ATCA 3/6cm radio limits
  27. GRB 060116: photometric redshift - the farthest GRB?
  28. Konus-Wind observation of GRB 060117
  29. GRB 060116: UKIRT IR Observations
  30. GRB 060117: Refined analysis of the Swift-BAT burst
  31. GRB 060117: FRAM optical afterglow candidate
  32. GRB 060117: nearby galaxy
  33. GRB 060116: VLT optical observations
  34. GRB 060116: Refined analysis of the Swift-BAT burst
  35. GRB 060116: XRT refined analysis
  36. GRB 060116: IR Candidate Afterglow
  37. GRB 060116: Swift/UVOT upper limits
  38. GRB060115: REM observations
  39. GRB 060110: XRT position and analysis
  40. GRB 060116 : Lulin optical limit
  41. GRB060116: Faulkes North observation
  42. GRB 060116: Swift-BAT detection of a burst
  43. GRB 060115: Refined analysis of the Swift-BAT burst
  44. GRB 060115: Swift/UVOT upper limits
  45. GRB 060114: REM observations
  46. GRB 060115: Swift XRT refined analysis
  47. GRB 060114: Swift/UVOT Observations
  48. GRB060115, optical observation
  49. GRB 060115: MITSuME optical afterglow candidate
  50. GRB 060115: Swift detection of a burst
  51. GRB060114, optical observation
  52. GRB060114: Faulkes North observation
  53. GRB 060108: IR observations of afterglow
  54. GRB 060108: Evidence for an XRT Position Offset
  55. GRB 060110: KAIT observations
  56. GRB 060111B: Swift XRT refined analysis
  57. GRB 060111B: MITSuME detection of optical afterglow
  58. GRB 060111B: TAROT optical observation
  59. GRB060111A: RTT150 optical observations
  60. GRB060111B: RTT150, possible host galaxy
  61. GRB 060111B: Refined analysis of the Swift-BAT burst
  62. GRB 060111(a): P60 Observations
  63. GRB 060111B: Gualba observatory limit
  64. GRB 060111B: Swift detection of a burst
  65. GRB 060111: Swift-BAT Refined Analysis
  66. GRB060111.2:_MASTER optical limit
  67. GRB 060108: VLT K-band observations
  68. GRB 060111: TAROT optical observation
  69. GRB 060111: Swift detection of a burst
  70. GRB 060110: Mitsume optical observations
  71. GRB 060110: Swift-BAT refined analysis
  72. GRB 060109: Swift-BAT refined analysis
  73. GRB 060108: z-band imaging from Gemini-North
  74. GRB 060110a: RAPTOR detection of early optical emission.
  75. GRB 060110: UKIRT K-band observations
  76. GRB 060110: IR Candidate Afterglow
  77. GRB060110, optical observation
  78. GRB 060110: Correction
  79. Correction to GRB 060109 XRT analysis
  80. GRB 050110: IR Observations
  81. GRB 060109: Refined Swift-XRT analysis
  82. GRB 060109: Swift/UVOT upper limits
  83. GRB060109, optical observation
  84. GRB 060108: ISAS early observations and near IR upper limit
  85. GRB060108: P200 Ks Observations
  86. GRB 060108: early UKIRT K-band observations
  87. GRB 060108: a dark burst?
  88. GRB 060108: Refined XRT analysis
  89. GRB 060108: VLT J-band observations
  90. GRB 060108: Mitsume optical observations
  91. GRB 060108: Swift/UVOT upper limits
  92. GRB 060105: quick look analysis of the Suzaku/XIS afterglow observation
  93. GRB060108: SDSS pre-burst observations
  94. GRB060108: Faulkes Telescope observation
  95. GRB060108, optical observation
  96. GRB 060108: Refined analysis of the Swift-BAT burst
  97. GRB060108: Swift detection of its 100th GRB
  98. GRB 060105: ISAS observations and near IR upper limit
  99. GRB 060105: Swift/UVOT upper limits
  100. GRB 060105: Mitsume 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