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"
  1. GRB 981220 and GRB 981226, optical observations
  2. GRB981226 Optical Observations
  3. GRB981226 BeppoSAX follow up
  4. GRB 981226 radio observations
  5. GRB 981226
  6. GRB 981226 optical observations
  7. radio observations of GRB 981226
  8. GRB981220 B, R and I band observations
  9. GRB981226, BeppoSAX-NFI follow-up
  10. Optical Observations of GRB981226
  11. GRB 981220:Optical Observations
  12. GRB 981220 optical R and I observations
  13. GRB981226, BeppoSAX Christmas GRB
  14. GRB 981226 - Infrared Observations
  15. GRB 981226 optical observations
  16. GRB 981220
  17. GRB 981220, radio observations
  18. GRB981226 Optical Observation
  19. GRB 981220, radio observations
  20. GRB 981220: BeppoSAX/GRBM results
  21. GRB981220 I-band Observations
  22. GRB981220 Optical Observations
  23. GRB 981220
  24. GRB 981220 Optical Observations
  25. GRB 981220, optical observations
  26. GRB 980326/Host Galaxy
  27. GRB981220 IPN error box
  28. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  29. BeppoSAX NFI Observation of GRB980425
  30. GRB980329 R,I flux calibration and R,I,K upper limits
  31. GRB980425 Optical Follow-up
  32. GRB980425: X-ray revised positions
  33. GRB 980923 BATSE Observations
  34. SGR1900+14, BeppoSAX-GRBM observations
  35. GRB980703 Very Long Baseline Interferometry
  36. GRB970508 optical observations
  37. GRB971214, association with a Galactic star?
  38. Optical Observations of the Host Galaxy of GRB 980519
  39. GRB980519, Optical Observations
  40. GRB980703, Host galaxy multicolor photometry
  41. GRB980703 - BeppoSAX/GRBM detection
  42. GRB 980703 (NFI observations)
  43. GRB980703 optical photometry
  44. GRB 980703: BATSE Observations
  45. GRB980703 optical observations
  46. GRB980703: Radio transient
  47. GRB980703 H-band Observations
  48. GRB 980703: Spectrum of the proposed optical counterpart
  49. RXTE Observation of GRB 980706
  50. GRB980703: Spectrum of the proposed optical counterpart
  51. GRB980703 Transient Optical Follow-Up
  52. GRB980703: LOTIS observation at early times
  53. GRB980613 Optical Observations
  54. GRB 980703
  55. GRB980703 (I band observations)
  56. GRB 980703 H-band Observations
  57. GRB980703 (optical R observations)
  58. GRB980706
  59. GRB980703: radio source/optical transient
  60. BeppoSAX NFI observations of GRB 980703
  61. GRB 980703: ASM Position & Intensity
  62. GRB980703
  63. GRB980519 observation report
  64. GRB980703 optical followup
  65. SGR1627-41
  66. Radio observations of SGRs
  67. SGR1900+14 field optical observations
  68. GRB 980613 Near-IR observations
  69. GRB980613, optical observations
  70. GRB 980613: Optical transient and its host galaxy
  71. SGR1627-41, RXTE/ASM observations
  72. SGR1627-41, Refined IPN annulus location
  73. GRB 980613: Detection of the probable host galaxy
  74. Reduced error box of SGR 1627-41
  75. GRB 980613: BATSE Observations
  76. SGR1627-41, BeppoSAX-GRBM detections
  77. SGR 1627-41
  78. GRB 980613 Optical Observations
  79. GRB 980613 optical observations
  80. Discovery of a new SGR source, SGR1627-41
  81. GRB980613 Optical Observations
  82. GRB980613 observations from Palomar
  83. GRB980613 BeppoSAX-NFI follow up
  84. GRB 980613 new optical/IR observations
  85. GRB 980613 optical/IR obs.
  86. GRB980613 Near Infra-Red Observations
  87. GRB980611
  88. GRB980613, BeppoSAX WFC positions
  89. GRB971214 Secondary Standards
  90. SGR 1900+14
  91. GRB980519 Secondary Standards
  92. SGR1900+14
  93. SGR1900+14
  94. BATSE on-board GRB trigger change
  95. GRB 980519 Optical Observations
  96. GRB980519 optical observations
  97. GRB980519 I-band observations
  98. GRB 980519
  99. GRB980519 optical observations
  100. GRB 980519 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