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"

37746 results found.

  1. IPN triangulation of GRB030422 (two large error boxes)
  2. GRB 030329 3.5 and 6 cm radio observations at RTF-32 telescope
  3. IPN triangulation of GRB030421 (annulus)
  4. MASTER:optical observations GRB030418
  5. MASTER:optical observations probable GRB030414
  6. GRB030329: 444 AAVSO Measurements
  7. IPN triangulation of GRB030419 (annulus)
  8. MASTER:optical observations GRB030416
  9. ROTSE-III prompt optical detections of GRB 030418
  10. GRB030418: Upper limits from recent and historical observations.
  11. GRB030418: Kiso near infrared observations
  12. GRB 030418: Optical afterglow
  13. GRB 030418: Finder for afterglow candidate
  14. GRB 030418: Optical afterglow candidate
  15. GRB 030329 OT position
  16. OT GRB 030329: early UBVRcIc spectral evolution
  17. GRB030329, UBVRI polarimetry, R-polarization
  18. GRB 030329: SARA Optical Observations
  19. OT GRB 030329: early spectrum
  20. GRB030329: VR Photometry at TNG
  21. GRB030324: Candidate Optical Afterglow (Erratum)
  22. GRB030324: Candidate Optical Afterglow
  23. IPN triangulation of GRB030414 (small error box)
  24. GRB 030413: Optical Observations
  25. GRB 030329 Rc observations
  26. IPN triangulation of GRB030413 (small error box)
  27. IPN triangulation of GRB030410 (annulus)
  28. Superluminal motion in GRB 030329 (Correction)
  29. Superluminal motion in GRB 030329
  30. GRB 030329 and SN 2003dh
  31. GRB030329, optical position
  32. GRB 030329 VLBA Observations
  33. IPN triangulation of GRB030406 (small error box)
  34. IPN triangulation of GRB050403 (small error box)
  35. IPN triangulation of GRB030403 (annulus)
  36. GRB 030329: BVRI photometry at Asiago
  37. GRB 030329, light curve flattens
  38. GRB 030329: VLT V-band photometry
  39. If the SN/GRB connection confirmed
  40. GRB 030329: Supernova Confirmed
  41. GRB030329: RTT150 optical observations
  42. GRB030329: Near Infrared Observations at Gunma
  43. GRB030329: HET spectroscopic monitoring
  44. Kiso observation of the GRB030329 at April 6
  45. GRB 030329, color evolution
  46. GRB030328, UBVRcIc field photometry
  47. GRB 030329 Optical observations
  48. GRB 030329, color evolution
  49. GRB 030329: possible color change
  50. GRB030329: RTT150 optical observations
  51. GRB 030329: Supernova Spectrum Emerging
  52. GRB030329: Kiso B and R band observations
  53. GRB030329: RTT150 optical observation
  54. GRB030329: More AAVSO VR obs
  55. GRB030328: R upper limit after 6 hours by MASTER
  56. GRB 030329: BV photographic observations
  57. GRB 030329: SARA Optical Observations
  58. GRB 030329: SARA Optical Observations
  59. GRB030329, fading resumes
  60. GRB 030329, BVRI photometry
  61. SDSS 0.5m PT observations of GRB030329 (correction)
  62. SDSS 0.5m PT observations of GRB030329
  63. GRB 030329, Optical observations
  64. GRB 030329, nearby galaxies
  65. GRB030329, cessation of fading
  66. GRB030329 Radio 23/43/90 GHz observations at Nobeyama
  67. GRB 030329: Sub-millimeter detection
  68. GRB 030329: SARA Optical Observations
  69. GRB 030329: SARA Optical Observations
  70. OT GRB light curves and SN predictions
  71. GRB030329, optical observation
  72. GRB030329, new UBVRcIc field photometry
  73. GRB 030329, light curve and SN prediction
  74. GRB030329: optical observations at Tokyo Tech
  75. GRB 030329: optical observations
  76. GRB030329: multiple re-brightening phases
  77. GRB 030329, BRI photometry
  78. GRB 030329 , SPM optical observations
  79. GRB 030329: Radio observations at GMRT
  80. Further AAVSO V,B,R observations of GRB030329
  81. GRB 030329: Additional Mt. Laguna Optical Observations
  82. GRB 030329: SARA Optical Observations
  83. GRB 030329: Observations with ANDICAM
  84. GRB030329: further optical photometry and evidence for a light curve discontinuity
  85. GRB 030329: Correction to GCN 2056
  86. GRB 030329: fitting parameters and re-brightening
  87. GRB 030329: KAIT optical photometry
  88. GRB030329 Further RBO Optical Observations
  89. triangulation of GRB 030331 (single error box)
  90. GRB030329 - OT rebrightens
  91. GRB 030329: SARA Optical Observations
  92. AAVSO V & R observations of GRB030329
  93. IPN triangulation of GRB030331 (annulus)
  94. GRB 030329: optical observations
  95. IPN triangulation of GRB030329b (large error box)
  96. GRB 030329: beginning of the new fading phase in optical band
  97. GRB 030329, optical spectroscopy
  98. GRB 030329: fading X-ray afterglow with RXTE
  99. GRB 030329: optical photometry
  100. Photometry of GRB030329 - Constant OT Magnitude

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