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"

41646 results found.

  1. GRB000301C, optical observations
  2. GRB000301C 250 GHz detection
  3. GRB 000301C R-band observation
  4. GRB 000301C, Optical Observation
  5. GRB000301C, near-infrared observations (JHK' photometry)
  6. GRB 000301C: OT confirmed
  7. GRB000301c optical observations
  8. GRB 000301A, Radio Observations
  9. GRB000301C, optical observations
  10. GRB000301c, near-infrared observations
  11. GRB000301C
  12. GRB 000301C : Optical Candidate
  13. GRB000301C: RXTE/ASM and IPN localizations
  14. GRB000301A [IPN Position]
  15. GRB000226 [IPN Position]
  16. HST Observations of GRB 990712
  17. GRB 000214 near-IR observations
  18. GRB 000115 Optical observations
  19. GRB 000214, Radio Observations
  20. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  21. GRB000210, Radio Observations
  22. Correction to GCN 557 (GRB000214: BeppoSAX GRBM and WFC Detection)
  23. GRB 000115, BVRI field photometry
  24. GRB000214: BeppoSAX GRBM and WFC Detection
  25. IPN annulus for GRB000214
  26. Optical observations of GRB000210
  27. GRB000210 X-ray afterglow
  28. BeppoSAX GRB000214 ("S. Valentine's day GRB")
  29. GRB 000210: BATSE Observations
  30. Correction to Chandra Position of GRB000210 afterglow
  31. GRB000210, Radio Observations
  32. Chandra Observations of GRB000210 X-ray Afterglow
  33. IPN triangulation of GRB000210
  34. GRB000210: possible afterglow detection with BeppoSAX NFI
  35. GRB000201, Radio Observations
  36. GRB000210: BeppoSAX GRBM and WFC Detection
  37. Optical observations of GRB000131
  38. GRB000201 Optical Observations
  39. GRB 000201: TAROT optical observations
  40. GRB 000131 Optical Observations
  41. GRB000126 Optical Observations
  42. GRB 991208, radio observations
  43. BATSE+IPN location of GRB000131
  44. IPN localization of GRB000131
  45. GRB 000126, optical observations
  46. GRB000126, optical observations
  47. IPN localization of GRB000126
  48. GRB 000115 Optical observations
  49. BATSE Observations of GRB000115
  50. IPN annulus for GRB000115
  51. Second RXTE Observation of GRB 000115
  52. GRB991216, UBVRIJHK field photometry
  53. GRB991216 late optical observation
  54. Single IPN error box for GRB991229
  55. GCN resumes full operations
  56. GRB 991216 VLBA Observations
  57. BEPPOSAX GRBM Localization of GRB991226
  58. IPN error boxes for GRB991229
  59. GRB 991216: J band spectrophotometry
  60. GRB 991216: Detection of the Host and/or Absorber Galaxy
  61. IPN localization of GRB991226
  62. Single IPN error box for GRB991221
  63. IPN error boxes for GRB991221
  64. GRB 991216 RXTE ASM Observations
  65. IPN error box for GRB991216
  66. Lowell/Perkins observation of GRB 991216
  67. GRB 991217 (SAX J2303.2+0015) Optical observations
  68. GRB991217/SAX J2303.2+0015, optical observations
  69. Chandra observation of the X-ray afterglow of GRB991216
  70. GRB 991216, optical observations
  71. GRB 991216 Optical Observations
  72. GRB 991216 Optical spectroscopy/imaging
  73. VLT spectra of GRB991216
  74. GRB991216 Optical and IR observations
  75. K observations of GRB991216
  76. IR observations of GRB991216
  77. GRB991216 radio observations
  78. GRB 991217 (SAX J2303.2+0015) Optical observations
  79. GRB991216 radio observations
  80. GRB991216 Spectroscopy
  81. Lowell/Perkins observation of GRB 991216
  82. GRB991216, optical observations
  83. GRB991216 Optical and infrared observations of Beethoven Burst
  84. Refined IPN localization of GRB991216
  85. GRB 991216 Radio Observations
  86. GRB 991208 Keck Spectroscopy
  87. GRB 991208 Infrared Detection
  88. GRB991216
  89. GRB 991216--Summary of RXTE Observations
  90. GRB 991216 Optical Observations
  91. GRB 991216, optical observations
  92. GRB 991208 SAO-RAS Spectroscopy
  93. SAX J2303.2+0015: an x-ray/GRB?
  94. GRB 991216, Optical Transient
  95. GRB 991216, Optical Afterglow
  96. GRB991216 ('Beethoven Burst') B, R, and K Observations
  97. GRB 991216: Comparison with DPOSS images
  98. GRB991216, infrared observations
  99. GRB991216 Optical Observations
  100. GRB 991208 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