Skip to main content
New! Super-Kamiokande JSON Notices and Schema v4.5.0. 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"
  1. GRB060526: afterglow fitting and probable jet break
  2. GRB 060526: RTT150 optical observations
  3. GRB060526: Optical counterpart from MIRO
  4. GRB060502b: optical observations
  5. GRB 060526: RTT150 optical observations
  6. GRB 060526: Tautenburg OT observation and light curve fitting
  7. GRB060526: optical observations
  8. GRB 060526: SMARTS optical/IR afterglow observations
  9. GRB060526: possible break in the optical light curve
  10. GRB 060526: REM observations
  11. GRB 060526: RTT150 optical observations, afterglow flattening
  12. GRB 060526: Optical Flare
  13. GRB 060526: MDM-2.4m Observations
  14. GRB 060526: Refined analysis of the Swift-BAT burst
  15. GRB 060526: RTT150 optical observations
  16. GRB060526: Further Swift-UVOT Observations
  17. GRB060526, optical observations
  18. GRB 060526: Magellan Redshift
  19. GRB 060526 Lulin optical observation
  20. GRB 060526: Swift/XRT Team refined analysis
  21. GRB 060526: TNG optical observations
  22. GRB 060526: ROTSE-III Observations of Optical Counterpart
  23. GRB 060526: Watcher Observations
  24. GRB060526 - SDSS Pre-burst Observations
  25. GRB 060526: Continued emission for the Swift burst
  26. GRB 060526: Swift detection of a burst with x-ray and optical afterglow
  27. GRB060505: VLT observations of the optical afterglow
  28. GRB 060413 : WIDGET simultaneous optical observations
  29. GRB 060522: Swift/UVOT Observations: Correction
  30. GRB 060522: Swift/UVOT Observations of the Optical Afterglow
  31. XMM-Newton observation of GRB060510b
  32. GRB060512: Late-Time P200 Observations
  33. GRB060522: z = 5.11 Keck-LRIS Redshift
  34. GRB 060522: Swift/XRT Team refined analysis
  35. GRB 060522: Swift-BAT Refined Analysis
  36. GRB 060522: REM NIR observations
  37. GRB 060522: TNG optical observations
  38. GRB 060522: Swift detection of a burst with possible optical afterglow
  39. GRB 060512: reanalysis of optical spectra
  40. GRB 060515: NIR observation
  41. GRB 060210: Jet Break in the XRT light curve
  42. GRB 060516: Refined analysis of the Swift-BAT burst
  43. GRB 060512: TNG optical spectroscopy
  44. GRB 060516: Swift detection of a burst
  45. GRB060515: P200 NIR Observations
  46. GRB 060505 BAT refined analysis
  47. GRB 060515 BAT refined analysis
  48. GRB 060512: TAROT optical observation
  49. GRB 060515: Swift/XRT Team refined analysis
  50. GRB 060515: Swift/UVOT Upper Limits
  51. GRB 060515: Swift/XRT position
  52. GRB 060515: Super-LOTIS Observations
  53. GRB060515: Swift/UVOT initial observation
  54. GRB 060515: TAROT optical observation
  55. GRB 060515: ROTSE-III Optical Limits
  56. GRB 060515: Swift detection of a burst
  57. VLT optical spectroscopy of GRB 060512
  58. Swift/UVOT observations of GRB060512.
  59. GRB 060512: Subaru NIR observation
  60. GRB060512: Swift XRT Team refined analysis
  61. GRB 060512: 1.54m Kuiper Observations
  62. GRB 060512: Detection of NIR afterglow
  63. GRB 060512: P60 Observations
  64. GRB 060512: Swift-BAT Refined Analysis
  65. GRB 060505 - OT candidate + galaxy spectrum
  66. GRB 060512: optical decay
  67. GRB 060512: REM NIR observations
  68. GRB060512 - SDSS Pre-Burst Observations
  69. GRB060512 Name Correction: LT Afterglow detection
  70. GRB060512: Liverpool Telescope Afterglow detection
  71. GRB 060512: Swift detection of a burst with an optical afterglow
  72. GRB 060510A: Swift/UVOT Detection of an Optical Afterglow
  73. GRB 060505: X-ray afterglow - Correction -
  74. GRB 060505: X-ray afterglow
  75. Konus-Wind observation of GRB 060510A
  76. GRB060418: optical observations
  77. GRB 060428a, SMARTS optical/IR afterglow detection
  78. GRB060510B: Swift XRT refined analysis
  79. GRB 060510B: Swift/UVOT Upper Limits
  80. GRB 060510A: Refined analysis of the Swift-BAT burst
  81. GRB 060510B: Swift-BAT Refined Analysis
  82. GRB060510A: XRT refined analysis
  83. GRB060510 - SDSS Pre-Burst Observations
  84. GRB 060510b: Redshift
  85. GRB060510B : Faulkes North Telescope detection
  86. GRB 060510B : Planned XMM-Newton observation
  87. GRB 060510b: Gemini NIR observations
  88. GRB 060510B: Super-LOTIS Observations
  89. GRB 060510b: NIR observations
  90. GRB 060510B: Coordinate correction
  91. GRB 060510B: MDM Observations and candidate OT
  92. GRB 060510B: Swift detection of a burst
  93. GRB 060510: Swift detection of a burst with optical transient
  94. GRB060507: optical afterglow detection
  95. GRB060502B: improvement in the XRT afterglow position
  96. GRB 060507: BART limit
  97. GRB 060507: Final Refined analysis of the Swift-BAT burst
  98. GRB 060507: Swift-BAT Refined Analysis
  99. GRB 060505: PROMPT Observations
  100. GRB 060507: Swift/UVOT Upper Limits

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