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"

20484 results found.

  1. GRB000911: Optical observations
  2. GRB 000830: Optical observations
  3. GRB000830: Optical observations
  4. GRB000830, TNG B-band observations
  5. GRB000830: Optical observations
  6. GRB000210, Optical observations
  7. "Snapshot" afterglow IDs and GRB 000830
  8. GRB000830: Optical observations
  9. HST/STIS observations of the host galaxy of GRB 980329
  10. HST/STIS observations of the chaotic environment of GRB 980613
  11. SGR 1806-20 burst activity
  12. GRB000812, TNG R-band observations
  13. GRB000801 & GRB000730, Gamma Ray Observations
  14. GRB000730, Gamma Ray Observations
  15. GRB000812, Radio observations
  16. GRB000801, Gamma Ray Observations
  17. GRB000801, VLT-Antu R-band observations
  18. GRB000301C, UBVI optical observations
  19. GRB000801, Radio Observations
  20. GRB 990510: Possible detection of a host galaxy
  21. GRB 000727, optical observations
  22. GRB 990705, HST/STIS observations of the host galaxy
  23. GRB 990712: Late time HST/STIS Observations
  24. GRB 991216, HST/STIS observations
  25. GRB000620, Radio Observations
  26. GRB981226, HST/STIS observations of the host galaxy
  27. GRB000630, optical observations
  28. GRB 000630: Detection of the Optical Afterglow
  29. GRB000630, Optical Observations
  30. GRB000630, optical observations
  31. GRB000630, optical observations
  32. GRB000630, optical observations
  33. GRB000630, optical observations
  34. GRB000630: Optical observations
  35. GRB000630, Radio Observations
  36. possible optical counterpart of GRB 000630
  37. GRB 000623, optical observations
  38. GRB 000620, optical observations
  39. GRB000418, HST/STIS Observations
  40. GRB990123: Late-time HST/STIS observations of the host
  41. GRB 990506, HST/STIS Observations of the Host Galaxy
  42. GRB 000620: J-band observations
  43. GRB000620, optical observations
  44. GRB000615: H-band observations
  45. GRB990308, HST/STIS observations of the host galaxy
  46. GRB000620 - Optical observations
  47. GRB000620 Optical observations
  48. GRB000615, Radio observations
  49. GRB000607, optical observations
  50. GRB 000615: NIR further observations
  51. GRB990123, HST/STIS observations of the host galaxy
  52. GRB000616 optical observations
  53. GRB 000615, near-infrared observations
  54. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  55. GRB000615, further R-band photometry
  56. GRB 000615: NIR observations
  57. GRB000615, R-band photometry
  58. GRB980425, HST/STIS observations of the host galaxy
  59. GRB 000301C: Further Late-Time HST/STIS observations
  60. GRB980519, HST/STIS observations of the host galaxy
  61. GRB000607, Radio Observations
  62. GRB000604 - Optical observations
  63. GRB000604, optical observations
  64. GRB000528, optical observations at ESO
  65. GRB 000604 optical observations
  66. GRB 000418: Detection of the Host Galaxy
  67. GRB000604, optical observations, comparison with DPOSS
  68. GRB000528, Radio Observations
  69. GRB000529: Optical Observations
  70. GRB000519: Optical observations
  71. GRB000528: BeppoSAX GRBM observations
  72. GRB 000528 Optical Observations
  73. Re: GRB000508B : Optical observations
  74. GRB000508B, optical photometry
  75. Possible GRB-related phenomenon
  76. GRB 000424 Optical Observations
  77. The redshift of GRB 000418
  78. GRB000424, optical observations
  79. GRB000424 Optical Observations
  80. GRB000424, optical observations
  81. GRB000424, optical observations
  82. GRB 000424, Optical Observations
  83. GRB 000418, Optical Observation
  84. GRB000418, near-infrared observations
  85. GRB000416 Optical Observations
  86. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  87. GRB000416 BRJK observations
  88. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  89. Budget cuts in BeppoSAX operations: impact on GRB observations
  90. GRB 000408, optical observations
  91. GRB000408: Optical CCD Observations from MIRO
  92. GRB000408, lotis optical observations
  93. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  94. GRB000326 Optical Observations
  95. GRB000301C - R magnitude lower limit
  96. GRB000326, Further VLA observations
  97. GRB 000323, optical observations
  98. GRB 000326: Optical Observations
  99. GRB000326, Radio observations
  100. GRB 000307 optical observations

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