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"

3559 results found.

  1. Fermi trigger No 663966693: Global MASTER-Net observations report
  2. Fermi-GBM Observations of Recent Bursting Activity from SGR J1935+2154
  3. Fermi GRB 220111A: Global MASTER-Net observations report
  4. Konus-Wind detection of GRB 220101A
  5. Fermi trigger No 663406755: Global MASTER-Net observations report
  6. GRB 220107A: AbAO and Terskol optical observations
  7. GRB 211227A: Deep early CAHA 2.2m/CAFOS observation
  8. Fermi GRB 211229A: Global MASTER-Net observations report
  9. Konus-Wind detection of the intermediate flare from SGR 1935+2154
  10. GRB 211227A: Liverpool Telescope upper limits
  11. GRB 211227A: LCO Optical Observations
  12. GRB 211227A: MAXI/GSC detection
  13. GRB 211225A: MITSuME Akeno optical upper limits
  14. Swift GRB 211225B: Global MASTER-Net observations report
  15. Fermi GRB 211225C: Global MASTER-Net observations report
  16. GRB 211225A/MAXI J0827-071: MAXI/GSC detection
  17. GRB 211218A: MITSuME Akeno optical upper limits
  18. GRB 211218A, MAXI J0909-041: MAXI/GSC detection
  19. MAXI GRB211218.04: Global MASTER-Net observations report
  20. GRB 211212A: Fermi GBM Final Real-time Localization
  21. Fermi GRB 211211B: Global MASTER-Net observations report
  22. Fermi trigger No 660736561: Global MASTER-Net observations report
  23. Fermi GRB 211204A: Global MASTER-Net observations report
  24. Fermi GRB 211130A: Global MASTER-Net observations report
  25. GRB 211129A: Swift/UVOT Upper Limits
  26. IceCube-Cascade 211128A: Upper limits from a search for additional neutrino events in IceCube
  27. IPN triangulation of GRB 211120A
  28. Fermi trigger No 658971499: Global MASTER-Net observations report
  29. Fermi trigger No 658755664: Global MASTER-Net observations report
  30. GRB 211115A: MAXI/GSC detection
  31. Fermi trigger No 658214822: Global MASTER-Net observations report
  32. Fermi GRB 211109B: Global MASTER-Net observations report
  33. GRB 211023A: SAO RAS optical observations
  34. Swift Trigger 1082569 is probably not a GRB
  35. GRB 211023B: Subaru optical observation
  36. GRB 211024A: MITSuME Akeno optical observation
  37. GRB 211023B: MITSuME Akeno optical upper limits
  38. Fermi GRB 211031A: Global MASTER-Net observations report
  39. GRB 211023A: 1.3m DFOT Optical Observations
  40. GRB 211023A: Terskol optical observations
  41. Fermi GRB 211027A: Global MASTER-Net observations report
  42. GRB 210610B: Sintesz-Newton/CrAO optical observations
  43. GRB 211023B: BOOTES-4/MET and 1.5m OSN optical upper limit
  44. GRB 211018A: Fermi GBM observation
  45. GRB 211018A: Fermi-LAT detection
  46. Fermi trigger No 655401471: Global MASTER-Net observations report
  47. Fermi trigger No 654854799: Global MASTER-Net observations report
  48. GRB 210928A: Fermi GBM observation
  49. GRB 210927A: GIT optical follow-up of ZTF21acdwctm.
  50. Fermi GRB 210929B: Global MASTER-Net observations report
  51. GRB 210919A OSN 1.5m Source Confirmation
  52. IceCube Alert 210922.76: Global MASTER-Net observations report
  53. GRB 210919A: Swift detection of a short burst
  54. Konus-Wind observation of the recent SGR 1935+2154 activity
  55. Fermi GBM observation of another bright burst in the direction of SGR 1935+2154
  56. GECAM observations of bursts from SGR J1935+2154 (2021-09-11T07 to 2021-09-12T08)
  57. Fermi trigger No 653084584: Global MASTER-Net observations report
  58. Fermi trigger No 653083551: Global MASTER-Net observations report
  59. Fermi trigger No 653066130: Global MASTER-Net observations report
  60. Fermi trigger No 653022153: Global MASTER-Net observations report
  61. IPN triangulation of a bright burst from SGR 1935+2154
  62. Fermi trigger No 652944960: Global MASTER-Net observations report
  63. Fermi trigger No 652906639: Global MASTER-Net observations report
  64. Fermi trigger No 652585475: Global MASTER-Net observations report
  65. Fermi GRB 210903A: Global MASTER-Net observations report
  66. GRB 210827A: BOOTES-5/JGT optical upper limit
  67. Integral GRB210829.14: Global MASTER-Net observations report
  68. Fermi GRB 210827A: Global MASTER-Net observations report
  69. GRB 210824A: Fermi GBM Observation
  70. GRB 210822B: DDOTI Upper Limits on the Afterglow
  71. Fermi GRB 210822B: Global MASTER-Net observations report
  72. Fermi GRB 210821A: Global MASTER-Net observations report
  73. GRB 210821A: Fermi GBM Final Real-time Localization
  74. Fermi trigger No 651110719: Global MASTER-Net observations report
  75. Fermi GRB 210813A: Global MASTER-Net observations report
  76. GRB 210807A: Tautenburg observations
  77. GRB 210807A: Swift-BAT refined analysis
  78. GRB 210807C: Fermi GBM detection
  79. Fermi GRB 210807C: Global MASTER-Net observations report
  80. Swift GRB 210807A: Global MASTER-Net observations report
  81. IPN Triangulation of a bright burst from SGR 1935+2154
  82. Fermi trigger No 649814537: Global MASTER-Net observations report
  83. GRB 210731A: MeerLICHT optical afterglow detection
  84. GRB210731A: Enhanced Swift-XRT position
  85. Fermi trigger No 648959581: Global MASTER-Net observations report
  86. Fermi trigger No 648868114: Global MASTER-Net observations report
  87. Swift GRB210724.84: Global MASTER-Net observations report
  88. Fermi trigger No 648602917: Global MASTER-Net observations report
  89. Fermi trigger No 648278666: Global MASTER-Net observations report
  90. GRB 210715B: DDOTI Upper Limits on the Afterglow
  91. Fermi trigger No 647942198: Global MASTER-Net observations report
  92. Fermi trigger No 647805873: Global MASTER-Net observations report
  93. Fermi trigger No 647641569: Global MASTER-Net observations report
  94. Fermi trigger No 647624281: Global MASTER-Net observations report
  95. Fermi GRB 210709A: Global MASTER-Net observations report
  96. GRB 210708B: Swift detection of a possible burst
  97. Fermi trigger No 647365516: Global MASTER-Net observations report
  98. Integral GRB210707.02: Global MASTER-Net observations report
  99. Fermi trigger No 647108723: Global MASTER-Net observations report
  100. Fermi trigger No 647120009: Global MASTER-Net observations report

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