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"

36154 results found.

  1. GRB000604, optical observations, comparison with DPOSS
  2. GRB000604 [IPN Position]
  3. X-ray Afterglow of GRB 000529
  4. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  5. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  6. IPN localization and time history of GRB000528
  7. New IPN localization of GRB000529
  8. GRB 000528 - WFC measurements
  9. GRB000528: BeppoSAX GRBM observations
  10. GRB 000528 Optical Observations
  11. GRB000519, BVRI field photometry
  12. IPN triangulation of GRB000519
  13. IPN triangulation of GRB000516
  14. Re: GRB000508B : Optical observations
  15. GRB 000418, Optical observation
  16. GRB000508B, optical photometry
  17. GRB000508B, BVR field photometry
  18. Possible GRB-related phenomenon
  19. RXTE/ASM and IPN localization of GRB 000508B
  20. GRB000424, UBVRI field photometry
  21. GRB 000424 Optical Observations
  22. GRB000418, UBVRI field photometry update
  23. The redshift of GRB 000418
  24. GRB 000429, optical observation
  25. GRB 000429, UBVRI field photometry
  26. IPN localization of GRB000429
  27. GRB 000418, UBVRI field photometry
  28. GRB000418, K'-band photometry
  29. GRB 000418, Optical Observation
  30. GRB 000418, optical observation
  31. GRB000424 Optical Observations
  32. GRB 000418, Optical Observation
  33. GRB 000424, Optical Observations
  34. GRB 000418, Optical Observation
  35. GRB000418, near-infrared observations
  36. Correction to IPN error box for GRB000419
  37. IPN error box for GRB000418
  38. GRB000419 [IPN Position]
  39. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  40. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  41. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  42. Budget cuts in BeppoSAX operations: impact on GRB observations
  43. GRB 000408, optical observations
  44. Refined IPN error box for GRB000408
  45. GRB 991208, UBVRI field photometry
  46. GRB000301c results
  47. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  48. GRB000408 [IPN Position]
  49. GRB000326 Optical Observations
  50. GRB000301C - Addendum to GCN 623
  51. GRB000301C - R magnitude lower limit
  52. GRB 000323, optical observations
  53. GRB 000326: Optical Observations
  54. GRB000326, Radio observations
  55. GRB000326 [IPN Position]
  56. GRB 000307 optical observations
  57. GRB000323 [IPN Position]
  58. GRB000315 [IPN Positions]
  59. GRB 000313 - optical transient in the BATSE error box
  60. GRB000301C - B and R photometry
  61. GRB000301C - R photometry
  62. GRB 000307, Optical Observations
  63. GRB 000307, BVRI Field Photometry
  64. GRB 000301C: Optical Spectrum and Redshift
  65. GRB 000301C: Optical Spectrum and Redshift
  66. GRB 000301C: A Precise Redshift Determination
  67. GRB 000301C, Optical Observation
  68. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  69. GRB 000301C: HST/STIS CCD Imaging of the field
  70. IPN error box for GRB000307
  71. GRB 000301c: K' observations
  72. GRB000301C, optical R-band observations
  73. GRB000301c - R photometry and nearby faint source confirmation
  74. GRB 000301C, Optical Observation
  75. GRB 000301c: K' observations
  76. GRB 000301C Optical Observations
  77. GRB 000301C: K' Observations
  78. GRB000301C - Host galaxy not detected in R (?)
  79. Optical observations of GRB000301c
  80. GRB000301C optical observations
  81. GRB 000301c near-IR observations
  82. GRB 000301C, Optical Color
  83. GRB000301C, Optical Spectroscopy
  84. GRB 000301C, UBVRI field photometry
  85. GRB 000301C, Optical Observation
  86. GRB000301C 250 GHz detection
  87. GRB 000301C R-band observation
  88. GRB 000301C, Optical Observation
  89. GRB000301C, near-infrared observations (JHK' photometry)
  90. GRB 000301C: OT confirmed
  91. GRB000301c optical observations
  92. GRB 000301A, Radio Observations
  93. GRB000301C, optical observations
  94. GRB000301c, near-infrared observations
  95. GRB000301C
  96. GRB 000301C : Optical Candidate
  97. GRB000301C: RXTE/ASM and IPN localizations
  98. GRB000226 [IPN Position]
  99. HST Observations of GRB 990712
  100. GRB 000214 near-IR observations

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