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"

17032 results found.

  1. GRB 011030: TNG K-band observation
  2. XRF011030: J and K band observations
  3. XRF011030: Chandra Observations
  4. GRB011030: Z-band observations
  5. Non-triggered burst 011030 ("GRB 011030")
  6. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  7. GRB 970828: HST Observations of the Host Galaxy
  8. GRB 000131: HST Detection of the Host Galaxy
  9. GRB 970828: HST Observations of the Host Galaxy
  10. GRB010921, optical observation
  11. GRB011019: Subaru Optical Observations
  12. GRB011030 - further refinement WFC position
  13. GRB011030: radio search
  14. GRB 010921: Possible supernova component
  15. GRB010921, optical observation at early time
  16. GRB 010921, I-band observations
  17. GRB011019, optical observations
  18. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  19. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  20. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  21. GRB010928(=H1770): Localization of a Long GRB by HETE
  22. GRB010921, negative optical observations
  23. GRB010921 field photometry
  24. GRB000926, Host Galaxy Observations
  25. GRB001109, Host Galaxy Spectroscopic Observations
  26. Probable SGR or Short Duration GRB Detected by HETE
  27. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  28. GRB 010222 - WHT BVRI images
  29. GRB 010629 Optical Observations
  30. SGR1900+14: High Fluence Burst Localized by HETE
  31. GRB010629, optical observations
  32. IPN triangulation of GRB010629
  33. GRB010629: A Burst Localized by HETE
  34. SGR1900+14: Second Burst Localized by HETE
  35. SGR1900+14: A Burst Localized by HETE
  36. SGR1806-20: A Second, Intense Burst Localized by HETE
  37. SGR1806-20: Localization by HETE
  38. HETE Fully-Automated GCN Notices
  39. GRB000301C: Late-time HST/STIS observation
  40. GRB010518: a faint BeppoSAX detection
  41. GRB000418: HST/STIS Second-epoch Observations
  42. X-ray precursors to the large flare from SGR 1900+14
  43. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  44. Millimeter observation of SGR 1900+14
  45. Chandra Observations of SGR 1900+14
  46. SGR1900+14, I-band observations
  47. GRB010412, field photometry
  48. Giant flare from SGR1900+14
  49. GRB 010326b Optical Observations
  50. GRB010412: BeppoSAX GRBM and WFC observations
  51. IPN Triangulation of GRB010412
  52. GRB010324, revised field photometry
  53. GRB 980326: Late-time HST/STIS observations
  54. GRB010324, field photometry
  55. GRB010326B, field photometry
  56. GRB010326, field photometry
  57. GRB010220, field photometry
  58. Further Optical Observations of GRB 010324
  59. GRB010222, CXO X-ray observations
  60. GRB010324, optical observations
  61. GRB010326B: Localization by HETE (2nd GRB for this date)
  62. GRB 010326 optical observations
  63. GRB010326: Refined Localization by HETE
  64. GRB010326: Localization by HETE
  65. Optical Observations of GRB 010324
  66. GRB010222, late-time optical observation
  67. Support extension to the BeppoSAX mission
  68. GRB 010222, Optical Observations
  69. GRB 010222: High-Resolution Keck Spectroscopy
  70. GRB 010222 HST/Chandra TOO
  71. GRB010222 further R-band photometry
  72. GRB 010222: Keck Spectroscopy
  73. GRB010214, field photometry
  74. GRB010222, field photometry
  75. GRB010222 further R-band photometry
  76. GRB 010222 Kyoto optical observation
  77. GRB010222 R-BAND OBSERVATION
  78. GRB010214 follow-up from Hanle
  79. GRB 010222: Near-IR Observations
  80. GRB 010222: Optical Observations
  81. GRB010222, radio observations
  82. GRB010222, optical observations
  83. GRB010222: BeppoSAX/NFI Observations
  84. GRB 010220, simultaneous optical observations
  85. GRB010220: BeppoSAX WFC and GRBM preliminary data
  86. GRB010214, optical observations
  87. GRB010214: BeppoSAX WFC and GRBM preliminary data
  88. GRB 010214: X-Ray afterglow
  89. GRB 010214 optical observation
  90. J-Band Observation of GRB 010214.
  91. GRB010213, Near-IR observations
  92. Possible InfraRed Transient of GRB 010214.
  93. GRB010213 detected by HETE
  94. IPN Status Report
  95. HETE Status
  96. Optical Observations of GRB 001018 at Keck
  97. Optical observations of GRB 001018 with JCAM
  98. GRB 001212 Optical Observation
  99. GRB 001212 Optical Observation
  100. GRB001120, 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