Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! 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"

36188 results found.

  1. GRB021211: Kiso Observations
  2. GRB021204: Kiso Observations
  3. GRB 021201, optical observations
  4. GRB 021211: Radio Observations
  5. GRB 021201 (short/hard), NOT observations
  6. SUB-MM SEARCH FOR GRB 021211
  7. GRB 021211 Milagro GeV/TeV Observations
  8. GRB 021211, R- and I-band observations
  9. GRB021211 - Upper limits from recent and historical observations
  10. GRB 021204: I-band Observations
  11. GRB021211 (=H2493): A Bright, Long GRB Localized by HETE-2 in Near-Real Time
  12. HETE 2493: Optical observations
  13. GRB 021204: Optical Observations at RIKEN
  14. GRB 021125: Radio Observations
  15. IPN triangulation of GRB021206 (small error box)
  16. IPN triangulation of GRB021206 (exceptionally bright; annulus only)
  17. IPN detection of renewed activity from SGR1806-20
  18. IPN triangulation of GRB021205 (large error box)
  19. GRB 021104, GRB 021112 and GRB 021113 - Milagro GeV/TeV Observations
  20. GRB021201, BVRcIc field photometry
  21. GRB 021201, Radio Observations
  22. GRB 021201: Optical Observations
  23. GRB 021201: BOOTES simultaneous optical observations
  24. IPN triangulation of GRB021201 (short/hard burst, small error box)
  25. Radio Catalog of GRB Afterglows
  26. GRB021004, late time optical observations
  27. GRB021004 Chandra Observation
  28. IPN detection of continued SGR1900+14 activity
  29. IPN triangulation of GRB021115 (annulus)
  30. IPN triangulation of GRB021125B (two large error boxes)
  31. IPN triangulation of GRB021119 (large error box)
  32. IPN triangulation of GRB021125B (annulus)
  33. Improved IPN error box for GRB021125
  34. IPN triangulation of GRB021125 (INTEGRAL BURST)
  35. GRB021125 : A long GRB localized by INTEGRAL
  36. IPN confirmation of the reactivation of SGR1900+14
  37. IPN detection of possible reactivation of SGR1900+14
  38. GRB021113, SPI ACS observation
  39. IPN triangulation of GRB021119 (annulus)
  40. GRB 021112: Afterglow or Variable Star?
  41. GRB021113: optical observations at Bisei
  42. GRB 021113: Evidence for a Dark Optical Afterglow
  43. GRB 021112, Radio Observations
  44. GRB021112, BVRI field photometry
  45. GRB 021112: Variable Source in R-band search
  46. GRB021112: Optical Observations
  47. GRB021113: Kiso Observations
  48. IPN triangulation of GRB021109 (portion of annulus)
  49. IPN triangulation of GRB021113 (=H2449; annulus)
  50. IPN triangulation of GRB021108 (CORRECTION; TWO LARGE ERROR BOXES)
  51. GRB 021113: Optical observations
  52. GRB 021112: RAPTOR Observations
  53. GRB 021113: Optical Observations
  54. GRB 021113: Optical Observations
  55. GRB021113 (=H2449): A Long GRB Localized by HETE
  56. GRB 021112: Optical Observations
  57. GRB 021112: R-band search
  58. IPN triangulation of GRB021108 (large error box)
  59. GRB021112 (=H2448): A Long GRB Localized by HETE
  60. GRB 021016: Optical Observations
  61. IPN triangulation of GRB021109 (annulus)
  62. IPN triangulation of GRB021108 (annulus)
  63. IPN triangulation of GRB021104 (annulus)
  64. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  65. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  66. SGR1900+14 activity, November 2-4, 2002
  67. GRB021104: Candidate present in DSS
  68. IPN triangulation of GRB021102 (annulus)
  69. IPN triangulation of a burst from SGR1900+14 on November 01, 2002
  70. IPN triangulation of a burst from SGR1900+14 on October 29 2002
  71. IPN triangulation of GRB021025 (portion of annulus)
  72. IPN triangulation of GRB021027 (single large error box)
  73. GRB021004, late-time optical observations
  74. IPN triangulation of GRB021027 (two large error boxes)
  75. GRB 021023: Infrared Imaging
  76. IPN triangulation of GRB021027 (annulus)
  77. GRB 021023: Curious K-band Source(s) Just Outside of IPN Localization
  78. IPN triangulation of GRB021025 (annulus)
  79. IPN triangulation of SGR1900+14, October 22 2002
  80. GRB 021004: optical observations
  81. IPN triangulation of GRB021023 (small error boc)
  82. GRB 020813; likely host galaxy.
  83. IPN triangulation of GRB021020 (smaller error box)
  84. IPN triangulation of GRB021020
  85. GRB 021008, radio observations
  86. GRB 021016, optical observations
  87. GRB 021004: VRI observations at TNG: possible break
  88. GRB021016, optical observations
  89. SGR1900+14: burst on October 10 2002
  90. GRB 021008, optical observations
  91. GRB021016(=H2397): A Long GRB Localized by HETE
  92. IPN triangulation of GRB021016 (small error box)
  93. IPN triangulation of GRB021014 (large error box)
  94. IPN triangulation of GRB021013 (single error box)
  95. GRB 021004: optical spectroscopy on Oct 11
  96. IPN triangulation of GRB021013 (two small error boxes)
  97. GRB021004: High-resolution optical spectroscopy
  98. IPN triangulation of GRB021013 (annulus)
  99. GRB021004, UBVRcIc field photometry update
  100. IPN triangulation of GRB021008 (single error box)

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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