Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to https://gcn.nasa.gov.
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 020418: Optical observations
  2. IPN triangulation of GRB020418
  3. GRB020405: VLT observations of the OT environment
  4. GRB020410: BeppoSAX NFI observations refined analysis
  5. GRB 020409: Optical Observations
  6. Mars Odyssey joins the IPN
  7. IPN triangulation of GRB020413
  8. GRB 020409, 2-nd epoch optical observations at Terskol.
  9. GRB020405: predicted break
  10. GRB 020409: Optical observations
  11. GRB 020409, No Optical Detection to R = 22
  12. GRB020410: second BeppoSAX NFI observation
  13. GRB 020409: No Evidence for an Optical Afterglow
  14. GRB 020409, 2nd epoch optical observations
  15. GRB 020331 Kyoto observation on March 31
  16. GRB 020409
  17. GRB 020409 SARA Observations
  18. GRB "020411"
  19. GRB 020409, No Optical Detection to R = 20
  20. GRB020410: BeppoSAX NFI observation
  21. GRB 020409: Optical observations
  22. April 11 BeppoSAX event (GRB020411) is likely not a GRB
  23. GRB 020410, optical observations
  24. BeppoSAX ALERT: possible GRB020411
  25. GRB 020409, optical observations
  26. GRB 020409: Optical Observations
  27. GRB020406(?), optical observations
  28. GRB020410, optical observations
  29. BeppoSAX ALERT: possible GRB020410
  30. X-ray afterglow of GRB020321
  31. BeppoSAX GRB : GRB020409
  32. GRB020331: Confirmation of Afterglow Candidate with Magellan
  33. GRB020405: VLT optical observations and V band decay slope
  34. GRB020331 optical observations with RIMOTS
  35. GRB020124 optical observations with RIBOTS/RIMOTS
  36. GRB 020321: Candidate X-ray Counterparts
  37. ASM GRB candidate 020406 refined error box
  38. GRB 020405: Moderate-resolution spectroscopy
  39. GRB020331: Optical Observations of Afterglow Candidate
  40. GRB020406(?), optical observations
  41. GRB020405: VLT optical observations
  42. Revised Photometry of the Optical Afterglow of GRB 020405
  43. GRB020405: OT observations
  44. GRB 020331: Candidate Optical Afterglow
  45. GRB 020405: Decay index
  46. Short RXTE/ASM transient 020406; may be a GRB
  47. GRB020405, Radio Observations
  48. GRB020405: VLT spectroscopy
  49. Fading Optical Afterglow and Possible Host Galaxy of GRB 020405
  50. V band observations of GRB020405
  51. GRB 020405, U-band observations
  52. GRB 020405: Optical afterglow candidate
  53. IPN localization of GRB020405
  54. GRB011212: Optical Observations
  55. GRB 020331: NIR Observations
  56. GRB 020331: NIR Observations
  57. GRB020331 NIR observation at KPNO (re-submission)
  58. GRB02033 NIR observation at KPNO
  59. GRB020331 field photometry
  60. GRB 020331 Optical Observations
  61. GRB 020331, NIR observations
  62. GRB 020331: Optical observations
  63. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  64. GRB 020321: Infrared observations
  65. GRB 020322: BeppoSAX observations of the X-ray afterglow
  66. SN 2002ap - peak brightness date (SN/GRB?)
  67. GRB011211: HST Observations of Optical Afterglow and Host Galaxy
  68. GRB 020322, Radio observations
  69. Near-Infrared Observations of GRB020322 at TIRGO
  70. GRB 020321, Radio Observations
  71. GRB 020322: Optical Observations
  72. GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow
  73. GRB 020321: Optical observations
  74. GRB020317 BVRI field photometry
  75. GRB011211 revised BVRI field photometry
  76. GRB020305 BVRI field photometry
  77. GRB020322 BVRI field photometry
  78. GRB 020322 optical observations
  79. GRB020322: Candidate Optical Afterglow
  80. GRB 020322 optical observation
  81. GRB020317 : Near IR Observations from Mt Abu Observatory
  82. GRB 020322: Optical Sources and Improved Astrometry
  83. GRB020322, optical observations
  84. GRB 020322: Optical candidate
  85. XMM-Newton observation of GRB020322
  86. GRB020322: Optical Observations
  87. GRB020322: BeppoSAX/NFI Observations
  88. Bepposax GRB020322 The second springtime BSAX GRB
  89. GRB 020321: Optical observations
  90. GRB 011121: Fourth Epoch of HST Imaging
  91. GRB020317: optical observations
  92. GRB020321 optical observations
  93. GRB020321: BeppoSAX/NFI Observations
  94. GRB020321: a faint BeppoSAX detection
  95. GRB020305: NIR observations
  96. GRB 020317 : KISO Optical Observations
  97. BeppoSAX ALERT: GRB020321, the "Springtime Burst"
  98. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  99. GRB 020305: Optical Observations
  100. GRB020317, 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