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"

11835 results found.

  1. GRB 260529A: GOTO tentative optical afterglow candidate
  2. Fermi GRB 260529A: Global MASTER-Net observations report
  3. GRB 260529A: Fermi GBM Final Real-time Localization
  4. GRB 260526A: GECAM-B observation
  5. Fermi trigger No 801580882: Global MASTER-Net observations report
  6. GRB 260525A: AstroSat CZTI detection
  7. Fermi GRB 260526A: Global MASTER-Net observations report
  8. GRB 260526A: Fermi GBM Final Real-time Localization
  9. Fermi GRB 260525A: Global MASTER-Net observations report
  10. GRB 260525A: Fermi GBM Final Real-time Localization
  11. GRB 260523B: AstroSat CZTI detection
  12. GRB 260523B: GECAM-B observation
  13. Fermi GRB 260523A: Global MASTER-Net observations report
  14. GRB 260523B: Fermi GBM Final Real-time Localization
  15. GRB 260523A: Fermi GBM Final Real-time Localization
  16. GRB 260522A: Fermi GBM Observation
  17. GRB 260522B: NuSTAR detection of prompt emission
  18. GRB 260522B: Fermi GBM Final Real-time Localization
  19. GRB 260522A: GOTO optical upper limit
  20. Fermi trigger No 801135305: Global MASTER-Net observations report
  21. Fermi GRB 260522A: Global MASTER-Net observations report
  22. GRB 260522A: Fermi-LAT detection
  23. GRB 260522A: Fermi GBM Final Real-time Localization
  24. GRB 260511A: iTelescope T-75 optical detection
  25. GRB 260520B: SVOM/GRM observation
  26. GRB 260411B: TERI Gamma-ray detection
  27. GRB 260407A: TERI Gamma-ray detection
  28. GRB 260307A: TERI Gamma-ray detection
  29. GRB 251118A: TERI Gamma-ray detection
  30. GRB 251113A: TERI Gamma-ray detection
  31. GRB 260428A: TERI Gamma-ray detection
  32. GRB 260520B: Fermi GBM Final Localization
  33. GRB 260520A: Fermi GBM Final Localization
  34. GRB 260519D: Fermi GBM Final Localization Correction
  35. GRB 260519B: Fermi GBM Final Localization
  36. GRB 260519A: Fermi GBM Final Localization
  37. GRB 260421B: radio detection with the VLA
  38. GRID detection of GRB 260511A
  39. Fermi GRB 260516C: Global MASTER-Net observations report
  40. GRB 260516C: Fermi GBM Final Real-time Localization
  41. Fermi Gamma-ray Burst Monitor trigger 800627191/260516518 is not a GRB
  42. Fermi GRB 260516B: Global MASTER-Net observations report
  43. GRB 260516B: Fermi GBM Final Real-time Localization
  44. Fermi Gamma-ray Burst Monitor trigger 800592653/260516119 is not a GRB
  45. GRB 260516A: Fermi GBM Final Real-time Localization
  46. GRID detection of GRB 260507A
  47. GRB 260510C: Glowbug gamma-ray detection
  48. IceCube-260504A: No Candidate Transients from the Zwicky Transient Facility
  49. GRB 260511B: NOT optical observations
  50. Konus-Wind detection of GRB 260512A
  51. GRB 260510C: CALET Gamma-Ray Burst Monitor detection
  52. IPN triangulation of GRB 260512A
  53. Fermi GRB 260514A: Global MASTER-Net observations report
  54. GRB 260512A: AstroSat CZTI detection
  55. GRB 260514A: Fermi GBM Final Real-time Localization
  56. Fermi GRB 260513A: Global MASTER-Net observations report
  57. Fermi GRB 260512A: Global MASTER-Net observations report
  58. GRB 260511B: further SAO RAS optical observations
  59. GRB 260513A: Fermi GBM Final Real-time Localization
  60. Konus-Wind detection of GRB 260511B
  61. GRB 260511B: further J-band observations by the SYSU 80 cm infrared telescope
  62. GRB 260511B: Calapai Observatory, Massa S. Giorgio (Messina), optical observation.
  63. GRB 260512A: NuSTAR detection of prompt emission
  64. GRB 260510C: Infrared J and Hs detections with MDM/MIRAGE
  65. GRB 260512A: Fermi GBM Final Real-time Localization
  66. GRB 260511A: Glowbug gamma-ray detection
  67. Konus-Wind detection of GRB 260511A
  68. MASS-Cube (GRID 2.0) detection of GRB 260511A
  69. MASS-Cube (GRID 2.0) detection of GRB 260507A
  70. GRB 260511B: SAO RAS optical observations
  71. GRB 260510D: Glowbug gamma-ray detection of a likely short burst
  72. GRB 260511B: FRAM-ORM optical detection
  73. GRB 260511A: EP-FXT follow-up observation
  74. GRB 260511B: EP-FXT follow-up observation
  75. GRB 260511B: LCO optical counterpart detection
  76. GRB260511B: MAO/AZT-22 optical observations
  77. GRB 260511A: SVOM/VT optical observations
  78. GRB 260511B: LCO optical observations
  79. GRB 260511B: OHP/T193 spectroscopic observations
  80. GRB 260511B: GOTO optical counterpart detection
  81. GRB 260511B: Xinglong 2.16m/BEFOSC redshift confirmation
  82. GRB 260510C: SVOM/COLIBRÍ (FM-GFT) further optical observations
  83. GRB 260511B: SVOM/VT optical observations
  84. GRB 260511B: SVOM/COLIBRÍ (FM-GFT) optical observations
  85. GRB 260511B: OSIRIS+/GTC redshift z=2.006
  86. GRB 260510C: Fermi GBM Observation
  87. GRB 260511A: REM near-infrared detection
  88. GRB 260511B: GROWTH-India Telescope optical observations
  89. GRB 260511B: AstroSat CZTI detection
  90. GRB 260506B: Glowbug gamma-ray detection
  91. GRB 260506A: Glowbug gamma-ray detection of a short burst
  92. GRB 260511B: J-band observations by the SYSU 80 cm infrared telescope
  93. GRB 260511B: NuSTAR detection of prompt emission
  94. GRB 260511A: NuSTAR detection of prompt emission
  95. GRB 260511B: Fermi GBM Detection
  96. GRB 260511C: Fermi GBM Final Real-time Localization
  97. GRB 260511B: SVOM/VT optical observation with VHF data
  98. GRB 260511B: TRT optical observation
  99. GRB 260511A: Fermi GBM Detection
  100. GRB 260511A: UTGO H50 optical afterglow observation

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