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"

19857 results found.

  1. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  2. GRB 011130: Magellan spectroscopy
  3. Sub-mm and Centimeter Detections of the Host Galaxy of GRB000418
  4. GRB 011130, K band observations
  5. GRB011130, optical observations
  6. GRB011130 (XRF011130) SDSS PT i-band observations
  7. XRF011130: Infrared Observations
  8. GRB011130 (=XRF011130): Revised Localization of an X-ray
  9. GRB 011121
  10. GRB 011121: J-band observations
  11. GRB 011121: NIR observations, host galaxy?
  12. GRB010921 - Milagro GeV/TeV Observations
  13. GRB 011121: HST Scheduled
  14. GRB011121: UBRI Observations
  15. GRB011121
  16. GRB 011121 J-Band Astrometry
  17. GRB 011121: Detection of Bright IR Counterpart
  18. GRB011121: possible redshift, continued decay
  19. GRB 011030: TNG K-band observation
  20. XRF011030: J and K band observations
  21. XRF011030: Chandra Observations
  22. GRB011030: Z-band observations
  23. The X-ray Flash 011030 ('GRB 011030')
  24. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  25. GRB 970828: HST Observations of the Host Galaxy
  26. GRB 000131: HST Detection of the Host Galaxy
  27. GRB 970828: HST Observations of the Host Galaxy
  28. GRB011019: Subaru Optical Observations
  29. GRB011030 - further refinement WFC position
  30. GRB011030: radio search
  31. GRB 010921: Possible supernova component
  32. GRB010921, optical observation at early time
  33. GRB 010921, I-band observations
  34. GRB011019, optical observations
  35. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  36. GRB010921: Spectroscopy of the Host Galaxy
  37. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  38. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  39. GRB010923 as seen by BeppoSAX GRBM
  40. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  41. GRB010921, negative optical observations
  42. GRB010921 field photometry
  43. GRB010921 Optical Observations
  44. HETE Trigger #1760 (GRB 010920B?): a new optical source
  45. GRB000926, Host Galaxy Observations
  46. GRB001109, Host Galaxy Spectroscopic Observations
  47. GRB 010222: HST observations -- host galaxy and late-time decay
  48. BeppoSAX/GRBM detection of GRB 010801
  49. GCN and HETE status
  50. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  51. GRB 010222 - WHT BVRI images
  52. GRB 010629 Optical Observations
  53. GRB010629: Optical Observations
  54. SGR1900+14: High Fluence Burst Localized by HETE
  55. GRB010629, optical observations
  56. GRB010629: A Burst Localized by HETE
  57. SGR1900+14: Second Burst Localized by HETE
  58. SGR1900+14: A Burst Localized by HETE
  59. SGR1806-20: A Second, Intense Burst Localized by HETE
  60. SGR1806-20: Localization by HETE
  61. IPN triangulation of GRB010613
  62. HETE Fully-Automated GCN Notices
  63. GRB000301C: Late-time HST/STIS observation
  64. GRB010518: a faint BeppoSAX detection
  65. GRB000418: HST/STIS Second-epoch Observations
  66. X-ray precursors to the large flare from SGR 1900+14
  67. SGR 1900+14 : RXTE observations
  68. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  69. Millimeter observation of SGR 1900+14
  70. SGR 1900+14, Chandra observations
  71. Chandra Observations of SGR 1900+14
  72. SGR1900+14, I-band observations
  73. IPN Triangulation of the Giant Flare from SGR1900+14
  74. GRB010412, field photometry
  75. Giant flare from SGR1900+14
  76. GRB 010326b Optical Observations
  77. GRB010412: BeppoSAX GRBM and WFC observations
  78. GRB010324, revised field photometry
  79. GRB 980326: Late-time HST/STIS observations
  80. GRB010324, field photometry
  81. GRB010326B, field photometry
  82. GRB010326, field photometry
  83. GRB010220, field photometry
  84. Further Optical Observations of GRB 010324
  85. GRB010222, CXO X-ray observations
  86. GRB010324, optical observations
  87. GRB010326B: Localization by HETE (2nd GRB for this date)
  88. GRB 010326 optical observations
  89. GRB010326: Refined Localization by HETE
  90. GRB010326: Localization by HETE
  91. Optical Observations of GRB 010324
  92. GRB010222, late-time optical observation
  93. Support extension to the BeppoSAX mission
  94. GRB 010222 - HEGRA GeV/TeV Observations
  95. GRB010222 - Optical observation
  96. GRB 010222, Optical Observations
  97. GRB 010214, I-band data
  98. GRB010222 further R-band photometry
  99. GRB 010222: Keck Spectroscopy
  100. GRB010214, field photometry

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