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"

4046 results found.

  1. IceCube Alert 210922.76: Global MASTER-Net observations report
  2. GRB 210919A: NOT upper limits
  3. Swift GRB 210919A: Global MASTER-Net observations report
  4. GECAM observations of bursts from SGR J1935+2154 (2021-09-13T01 to 2021-09-15T14)
  5. Konus-Wind observation of the recent SGR 1935+2154 activity
  6. GECAM observations of bursts from SGR J1935+2154 (2021-09-12T05 to 2021-09-13T01)
  7. AGILE observations of two bright bursts from SGR 1935+2154
  8. Fermi GBM observation of another bright burst in the direction of SGR 1935+2154
  9. Fermi trigger No 653151835: Global MASTER-Net observations report
  10. GRB 210912A: Mondy optical afterglow confirmation
  11. Swift GRB 210912A: Global MASTER-Net observations report
  12. GECAM observations of bursts from SGR J1935+2154 (2021-09-11T07 to 2021-09-12T08)
  13. Fermi trigger No 653084584: Global MASTER-Net observations report
  14. Fermi trigger No 653083551: Global MASTER-Net observations report
  15. Fermi trigger No 653066130: Global MASTER-Net observations report
  16. Fermi trigger No 653072474: Global MASTER-Net observations report
  17. Fermi trigger No 653054042: Global MASTER-Net observations report
  18. Fermi trigger No 653022153: Global MASTER-Net observations report
  19. Fermi GBM observation of a bright flare in the direction of SGR 1935+2154
  20. Konus-Wind detection of the second intermediate flare from SGR 1935+2154
  21. IPN triangulation of a bright burst from SGR 1935+2154
  22. GRB 210909B: GECAM detection
  23. GECAM observations of a series of bursts from SGR J1935+2154
  24. Swift detection of a burst from SGR Swift J1555.2-5402
  25. GECAM observation of a burst from SGR J1935+2154
  26. GECAM observation of a burst from SGR J1935+2154
  27. GRB 210619B: Maidanak and Assy optical observations, broken power law parametrization
  28. Fermi trigger No 652911693: Global MASTER-Net observations report
  29. Fermi trigger No 652906639: Global MASTER-Net observations report
  30. GECAM observation of a burst from SGR J1555.2-5402
  31. Fermi GBM trigger 652585475 / 210906073 is not a GRB
  32. Fermi trigger No 652585475: Global MASTER-Net observations report
  33. GRB 210827B: GECAM detection
  34. Fermi GBM observation of a burst from SGR J1555.2-5402
  35. Integral GRB210829.17: Global MASTER-Net observations report
  36. Integral GRB210829.14: Global MASTER-Net observations report
  37. Fermi GRB 210827A: Global MASTER-Net observations report
  38. POLAR detection of a SGR-like burst
  39. GRB 210824A: MITSuME Akeno optical upper limits
  40. Swift detection of an outburst from SGR Swift J1555.2-5402
  41. GRB 210822A: GECAM refined analysis
  42. Konus-Wind detection of GRB 210822A
  43. Fermi GRB 210822B: Global MASTER-Net observations report
  44. GRB 210822A: Nanshan/NEXT optical observations
  45. GRB 210822A: GECAM detection
  46. GRB 210820A: LT optical upper limit
  47. Fermi GRB 210813A: Global MASTER-Net observations report
  48. SGR 1935+2154: SPI INTEGRAL observations on 2021 August 5
  49. Fermi GRB 210807C: Global MASTER-Net observations report
  50. Fermi trigger No 650046564: Global MASTER-Net observations report
  51. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 August 5
  52. IPN Triangulation of a bright burst from SGR 1935+2154
  53. Fermi trigger No 649814537: Global MASTER-Net observations report
  54. Fermi trigger No 649684549: Global MASTER-Net observations report
  55. Swift GRB210731.62: Global MASTER-Net observations report
  56. GRB 210731A: MeerLICHT optical afterglow detection
  57. GRB 210730A: Campo Imperatore optical observations
  58. GRB 210726A: Chandra detection of the X-ray afterglow
  59. GRB 210730A: Swift detection of a burst near M82
  60. Fermi trigger No 648959581: Global MASTER-Net observations report
  61. Fermi trigger No 648868114: Global MASTER-Net observations report
  62. Fermi trigger No 648602917: Global MASTER-Net observations report
  63. GRB 210719A: GECAM detection
  64. IceCube-210717A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  65. GECAM detection of a short burst from SGR J1935+2154
  66. Recent activity of SGR 1935+2154 as observed by CGBM
  67. Fermi trigger No 647805873: Global MASTER-Net observations report
  68. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 10
  69. GECAM detection of a short burst from SGR J1935+2154
  70. Fermi trigger No 647641569: Global MASTER-Net observations report
  71. Fermi trigger No 647624281: Global MASTER-Net observations report
  72. GECAM detection of a short burst from SGR J1935+2154
  73. GECAM detection of a short burst from SGR 1935+2154
  74. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 7
  75. GECAM detection of a short burst from SGR 1935+2154
  76. Fermi trigger No 647365516: Global MASTER-Net observations report
  77. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 6
  78. Fermi GBM Observations of SGR J1935+2154
  79. Swift-BAT detection of a burst from SGR 1935+2154
  80. GECAM detection of a bright short burst from SGR 1935+2154
  81. Integral GRB210707.02: Global MASTER-Net observations report
  82. INTEGRAL detection of a burst from SGR 1935+2154
  83. IceCube-210629A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  84. Fermi-LAT Gamma-ray Observations of IceCube-210629A
  85. GRB 210627B: GECAM detection
  86. IceCube Alert 210629.76: Global MASTER-Net observations report
  87. IceCube-210629A - IceCube observation of a high-energy neutrino candidate track-like event
  88. Fermi trigger No 646443989: Global MASTER-Net observations report
  89. Fermi GRB 210627A: Global MASTER-Net observations report
  90. GRB 210627A: Fermi GBM Final Real-time Localization
  91. Fermi GRB 210626A: Global MASTER-Net observations report
  92. Fermi GRB 210625A: Global MASTER-Net observations report
  93. Fermi trigger No 646189108: Global MASTER-Net observations report
  94. Fermi GBM observation of a bright burst in the direction of SGR 1935+2154
  95. GRB 210619B: Abbey Ridge Observatory optical afterglow observation
  96. GECAM detection of GRB 210622B
  97. Swift Trigger 1057131: detection of a burst from SGR Swift J1555.2-5402
  98. GECAM detection of GRB 210619B
  99. Fermi GRB 210615A: Global MASTER-Net observations report
  100. Follow-up on HAWC Transient Monitoring Alert J0020+3108

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