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"

11529 results found.

  1. GRB 240916A INTEGRAL SPI ACS LIGHT CURVE
  2. GRB 240916A: Fermi GBM Final Real-time Localization
  3. Fermi Gamma-ray Burst Monitor trigger 748124309/240915846 is not a GRB
  4. EP240913a / GRB 240913C INTEGRAL SPI ACS LIGHT CURVE
  5. GRB 240913C: Fermi GBM detection
  6. GRB 240913C: Joint location by ETJASMIN
  7. GRB 240914B: AstroSat CZTI detection
  8. EP240913A / GRB 240913C: AstroSat CZTI detection
  9. GRB 240910A: SVOM/VT optical observations
  10. GRB 240914B: BALROG localization (Fermi Trigger 747990592 / GRB 240914298)
  11. EP240913a: A GRB Event
  12. GRB 240913B: Fermi GBM Final Real-time Localization
  13. Fermi Gamma-ray Burst Monitor trigger 747837485/240912526 is not a GRB
  14. Fermi trigger No 747920561: Global MASTER-Net observations report
  15. GRB 240912A: SVOM/GRM observation
  16. Fermi GRB 240913A: Global MASTER-Net observations report
  17. GRB 240913A: Fermi GBM Final Real-time Localization
  18. GRB 240912A: J-band observations with WINTER
  19. GRB 240912A: Fermi GBM Observation
  20. GRB 240912A: LCOGT detection and Legacy Surveys likely host galaxy
  21. Fermi Gamma-ray Burst Monitor trigger 747839931/240912555 is not a GRB
  22. GRB 240912A : INTEGRAL SPI ACS LIGHT CURVE
  23. GRB 240912B: Fermi GBM Final Real-time Localization
  24. GRB 240912A: NOT optical spectroscopy
  25. GRB 240912A: Redshift from OSIRIS+/GTC
  26. GRB 240910A: Redshift from OSIRIS+/GTC
  27. GRB 240912A: Fermi GBM Final Real-time Localization
  28. GRB 240910A: Fermi GBM Observation
  29. GRB 240910A: NOT optical observations
  30. GRB 240910A: Swift-XRT detection of GOTO24fvl/AT2024vfp
  31. GRB 240910A: JinShan optical observations
  32. GRB 240910A: GOTO candidate optical counterpart
  33. GRB 240710A: SVOM/GRM observation
  34. GRB 240910A: Swift ToO observations
  35. IPN triangulation of GRB 240905B (short)
  36. GRB 240825A: 7DT Optical Upper Limit
  37. GRB 240910A: GRBAlpha detection
  38. GRB 240910B: Fermi GBM Final Real-time Localization
  39. GRB 240910A: SVOM/GRM observation
  40. Fermi GRB 240910A: Global MASTER-Net observations report
  41. GRB 240910A: Fermi GBM Final Real-time Localization
  42. GRB 240905B: Fermi GBM Observation
  43. Fermi trigger No 747553301: Global MASTER-Net observations report
  44. GRB 240905B: GOTO optical upper limits
  45. Fermi GRB 240908A: Global MASTER-Net observations report
  46. GRB 240908A: Fermi GBM Final Real-time Localization
  47. GRB 240801A: SVOM/GRM observation
  48. GRB 240905B: Swift-XRT observations
  49. GRB 240905B: Fermi-LAT detection
  50. GRB 240905B: Swift ToO observations
  51. Fermi GRB 240905D: Global MASTER-Net observations report
  52. Fermi GRB 240905A: Global MASTER-Net observations report
  53. GRB 240825A: Montarrenti Observatory optical follow-up observations
  54. GRB 240905D: AstroSat CZTI detection
  55. GRB 240905A: SVOM/GRM observation
  56. Fermi GRB 240905B: Global MASTER-Net observations report
  57. GRB 240905D: Fermi GBM Final Real-time Localization
  58. GRB 240905B: AstroSat CZTI detection and localization
  59. GRB 240905C: Fermi GBM Final Real-time Localization
  60. GRB 240905B: Fermi GBM Final Real-time Localization
  61. GRB 240825A: ATCA Detection of Radio Counterpart
  62. GRB 240905A: Fermi GBM Final Real-time Localization
  63. Fermi Gamma-ray Burst Monitor trigger 747163821/240904729 is not a GRB
  64. Fermi trigger No 747163821: Global MASTER-Net observations report
  65. GRB 240828A: SVOM/GRM observation
  66. Fermi Gamma-ray Burst Monitor trigger 240831A is not a GRB
  67. GRB 240828A: GECAM detection
  68. GRB 240831B: Fermi GBM Final Localization
  69. Fermi Gamma-ray Burst Monitor trigger 746882332/240901471 is not a GRB
  70. Fermi trigger No 746923430: Global MASTER-Net observations report
  71. GRB 240828A: SAO RAS AS-500(2) optical observations
  72. Fermi trigger No 746882332: Global MASTER-Net observations report
  73. GRB 240825A: TSHAO Optical Upper Limit
  74. GRB 240829B: GRBAlpha detection
  75. Fermi trigger No 746816563: Global MASTER-Net observations report
  76. GRB 240831A: Fermi GBM Final Real-time Localization
  77. GRB 240825A: SOAR observations
  78. Fermi trigger No 746684112: Global MASTER-Net observations report
  79. GRB 240828A: SAO RAS optical observations
  80. Fermi trigger No 746587425: Global MASTER-Net observations report
  81. GRB 240829B: Fermi GBM Final Localization
  82. GRB 240828A: Fermi GBM Observation
  83. GRB 240629A: First GRB Detected by BurstCube
  84. GRB 240828A: KAIT Optical Afterglow Candidate
  85. GRB 240825A: SVOM/VT optical detection
  86. GRB 240828A: Swift-XRT afterglow detection
  87. GRB 240825A: further SAO RAS optical observations
  88. GRB 240828A: Fermi-LAT detection
  89. GRB 240828A: Tiled Swift observations
  90. GRB 240828A: AstroSat CZTI detection of a long burst
  91. Fermi GRB 240828A: Bassano Bresciano Observatory upper limit
  92. GRB 240825A: Upper limits from a neutrino search with IceCube
  93. Fermi GRB 240828A: Global MASTER-Net observations report
  94. Fermi trigger No 746438824: Global MASTER-Net observations report
  95. GRB 240828A: Fermi GBM Final Real-time Localization
  96. GRB 240821A: the second and third EP-FXT follow-up observations and afterglow candidates
  97. GRB 240825A: GECAM detection
  98. GRB 240825A: SAO RAS optical observations
  99. GRB 240825A: TNG optical photometry and spectroscopy
  100. GRB 240824B: Ondrejov D50 optical limit

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