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"

2744 results found.

  1. 030228: NOT A GRB
  2. GRB 030227, possible optical counterpart of XMM-Newton source
  3. GRB030227 - faint tentative OT candidate
  4. Possible break in the GRB 030226 light curve
  5. GRB 030217: Optical Observations at 4, 5, and 6 Days
  6. IPN triangulation of GRB030206 (annulus)
  7. GRB030131: Candidate Optical Afterglow
  8. IPN triangulation of GRB030117 (two large error boxes)
  9. Publicizing GRB Discoveries - A Message from NASA HQ
  10. GRB 030115 : Possible IR counterpart
  11. GRB030115: TAROT optical observations
  12. Possible GRB030113 seen by SPI ACS
  13. Probable GRB030112B seen by SPI ACS
  14. Possible GRB030111 seen by SPI ACS
  15. Possible GRB030110b seen by SPI ACS
  16. Possible GRB 030110 seen by SPI ACS
  17. Possible GRB 20030109 seen by SPI ACS
  18. Possible GRB20030107 seen by SPI-ACS
  19. Possible GRB 20030105 seen by SPI ACS
  20. IPN triangulation of GRB030101 (two large error boxes)
  21. GRB 021211, optical observations
  22. IPN detection of renewed activity from SGR1806-20
  23. IPN triangulation of GRB021125B (two large error boxes)
  24. IPN triangulation of GRB021119 (large error box)
  25. GRB021125 : A long GRB localized by INTEGRAL
  26. IPN detection of possible reactivation of SGR1900+14
  27. GRB021104: optical observations
  28. GRB021104: possible optical afterglow
  29. IPN triangulation of GRB021020
  30. GRB 021004: VRI observations at TNG: possible break
  31. IPN triangulation of GRB021013 (two small error boxes)
  32. IPN triangulation of GRB021013 (annulus)
  33. XRF 020903: flattening of the optical light curve.
  34. GRB021004, UBVRcIc field photometry update
  35. IPN triangulation of GRB021007 (annulus)
  36. GRB 021004: polarimetric observations
  37. GRB 021004: Optical Observations
  38. XRF020903: TNG and Asiago photometry
  39. XRF 020903: R band observations
  40. XRF 020903: Archival Optical Images
  41. IPN triangulation of GRB020926 (two large error boxes)
  42. IPN triangulation of GRB020923 (two error boxes)
  43. IPN annulus for GRB020923
  44. IPN triangulation of GRB020914B
  45. Improved IPN position for GRB020918 (two large error boxes)
  46. IPN annulus for GRB020914B
  47. IPN triangulation of GRB020911 (2 large error boxes)
  48. IPN triangulation of GRB020914 - clarification and additional information
  49. IPN triangulation of GRB020910
  50. IPN GCN Circulars now to be issued without restriction
  51. GRB 020813 : HST observations
  52. GRB020813: Magellan BVRI Photometry
  53. GRB020813: High-Resolution Optical Observations
  54. GRB020813: optical observations; possible host galaxy
  55. GRB020812: optical observations
  56. IPN triangulation of GRB020813
  57. GRB020812: possible afterglow candidate
  58. GRB020812: possible afterglow candidate
  59. GRB 020813 Afterglow Observations; Possible break
  60. GRB 020410: Discovery of Probable OT by HST
  61. IPN triangulation of GRB020706
  62. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  63. Fading Optical Source in the Field of GRB020531
  64. GRB 020531, simultaneous optical observations
  65. GRB020531 Optical observations with TAROT
  66. GRB020531 Optical observations with TAROT
  67. IPN triangulation of GRB020604
  68. Correction to IPN triangulation of GRB020603 (possible short/hard burst)
  69. IPN triangulation of GRB020603 (possible short/hard GRB)
  70. GRB 020531 optical observations with TAROT
  71. IPN detection of possible bursts from SGR1806-20
  72. GRB020427 BeppoSAX NFI Observation
  73. GRB020405: VLT observations of the OT environment
  74. GRB020405: predicted break
  75. April 11 BeppoSAX event (GRB020411) is likely not a GRB
  76. BeppoSAX ALERT: possible GRB020411
  77. GRB020406(?), optical observations
  78. GRB020410, optical observations
  79. BeppoSAX ALERT: possible GRB020410
  80. Fading Optical Afterglow and Possible Host Galaxy of GRB 020405
  81. GRB 020321, Radio Observations
  82. GRB020321: BeppoSAX/NFI Observations
  83. GRB 020317: Optical observations
  84. GRB 011121: HST Observations reveal an intermediate-time multicolor
  85. GRB011121, possible supernova association
  86. GRB020127: Further VLA Observations of Possible Counterparts
  87. GRB020127: Palomar and VLA Observations of Possible Counterparts
  88. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  89. SN 2002ap (SN/GRB?)
  90. Type Ib/c SN2002ap (SN/GRB?) Radio Observations
  91. VLT observations of GRB 020124: The fading optical/near-infrared afterglow
  92. GRB 020124 Optical Observations
  93. GRB optical counterpart candidate in GCN 1217 is M dwarf
  94. Possible optical counterpart to a GRB
  95. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  96. GRB 011130: Magellan spectroscopy
  97. GRB011130, optical observations
  98. GRB 011121: J-band observations
  99. GRB 011121: HST Scheduled
  100. GRB011121: fainter still

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