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"

32502 results found.

  1. GRB030501B triangulation (single error box)
  2. GRB 030329 Optical Observations
  3. GRB030328, optical observation
  4. GRB 030329, BVRI photometry
  5. GRB030429: Optical Observations
  6. GRB030501: TAROT candidate afterglow present in archival images
  7. GRB 030501: TAROT possible candidate counterpart
  8. IPN triangulation of GRB030501 (IBIS event; annulus)
  9. GRB 030429: confirmation of afterglow candidate
  10. GRB030425: CrAO optical observation
  11. GRB 030329 Oprical observations in Rozhen observatory
  12. GRB 030324: Radio Observations
  13. GRB030329 observed as a sudden ionospheric disturbance (SID)
  14. GRB030329, SPM optical observations
  15. GRB 030329, the review of the sky area in plate archive (1950-1998)
  16. GRB 030329: Spectral Evolution of SN 2003dh
  17. GRB 030329: optical spectropolarimetry at VLT
  18. GRB030329: optical polarization
  19. GRB030329, optical observation
  20. GRB030329: 444 AAVSO Measurements
  21. ROTSE-III prompt optical detections of GRB 030418
  22. GRB030418: Upper limits from recent and historical observations.
  23. GRB 030418: Optical afterglow
  24. GRB 030418: Finder for afterglow candidate
  25. GRB 030329 OT position
  26. GRB030329: Optical Observations
  27. OT GRB 030329: early UBVRcIc spectral evolution
  28. GRB030329, UBVRI polarimetry, R-polarization
  29. GRB 030329: SARA Optical Observations
  30. OT GRB 030329: early spectrum
  31. GRB030329: VR Photometry at TNG
  32. GRB030324: Candidate Optical Afterglow
  33. GRB 030413: Optical Observations
  34. GRB 030329 Rc observations
  35. Superluminal motion in GRB 030329 (Correction)
  36. Superluminal motion in GRB 030329
  37. GRB 030329 and SN 2003dh
  38. GRB030329, optical position
  39. GRB 030329 VLBA Observations
  40. GRB 030329: BVRI photometry at Asiago
  41. GRB 030329, light curve flattens
  42. GRB 030329: VLT V-band photometry
  43. If the SN/GRB connection confirmed
  44. GRB 030329: Supernova Confirmed
  45. GRB030329: RTT150 optical observations
  46. GRB030329: Near Infrared Observations at Gunma
  47. GRB030329: HET spectroscopic monitoring
  48. GRB 030329, color evolution
  49. GRB030328, UBVRcIc field photometry
  50. GRB030329: Optical observcations
  51. GRB030329: BV photographic observations
  52. GRB 030329 Optical observations
  53. GRB 030329, color evolution
  54. GRB 030329: possible color change
  55. GRB030329: RTT150 optical observations
  56. GRB 030329: Supernova Spectrum Emerging
  57. GRB030329: RTT150 optical observation
  58. GRB030329: More AAVSO VR obs
  59. GRB030328: R upper limit after 6 hours by MASTER
  60. GRB 030329: BV photographic observations
  61. GRB 030329: SARA Optical Observations
  62. GRB 030329: SARA Optical Observations
  63. GRB030329, fading resumes
  64. GRB 030329, BVRI photometry
  65. GRB030329: Optical observations
  66. SDSS 0.5m PT observations of GRB030329 (correction)
  67. SDSS 0.5m PT observations of GRB030329
  68. GRB 030329, Optical observations
  69. GRB 030329, nearby galaxies
  70. GRB030329, cessation of fading
  71. GRB030329: final R-band light curve by MASTER
  72. GRB030329 Radio 23/43/90 GHz observations at Nobeyama
  73. GRB 030329: Sub-millimeter detection
  74. GRB 030329: SARA Optical Observations
  75. GRB 030329: SARA Optical Observations
  76. OT GRB light curves and SN predictions
  77. GRB030329, optical observation
  78. GRB030329, optical observation
  79. GRB030329, new UBVRcIc field photometry
  80. GRB 030329, light curve and SN prediction
  81. GRB030329: optical observations at Tokyo Tech
  82. GRB 030329: optical observations
  83. GRB030329: multiple re-brightening phases
  84. GRB 030329, BRI photometry
  85. GRB030329: Optical observations at Teramo
  86. GRB030329: more 15GHz observations
  87. Further AAVSO V,B,R observations of GRB030329
  88. GRB 030329: Additional Mt. Laguna Optical Observations
  89. GRB 030329: SARA Optical Observations
  90. GRB 030329: Observations with ANDICAM
  91. GRB030329: Optical observations
  92. GRB 030329: Correction to GCN 2056
  93. GRB 030329: fitting parameters and re-brightening
  94. GRB 030329: KAIT optical photometry
  95. GRB030329 Further RBO Optical Observations
  96. triangulation of GRB 030331 (single error box)
  97. GRB030329 - OT rebrightens
  98. GRB 030329: SARA Optical Observations
  99. AAVSO V & R observations of GRB030329
  100. GRB 030329: optical 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