Skip to main content
Announcing GCN Classic Migration Survey, End of Legacy Circulars Email. 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').
  1. GRB980613 observations from Palomar
  2. GRB980613 BeppoSAX-NFI follow up
  3. GRB 980613 new optical/IR observations
  4. GRB 980613 optical/IR obs.
  5. GRB980613 Near Infra-Red Observations
  6. GRB980611
  7. GRB980613, BeppoSAX WFC positions
  8. GRB971214 Secondary Standards
  9. SGR 1900+14
  10. GRB980519 Secondary Standards
  11. SGR1900+14
  12. SGR1900+14
  13. BATSE on-board GRB trigger change
  14. GRB 980519 Optical Observations
  15. GRB980519 optical observations
  16. GRB980519 I-band observations
  17. GRB 980519
  18. GRB980519 optical observations
  19. GRB 980519 Optical Observations
  20. GRB980519 BATSE Observations
  21. GRB970519, optical follow-up at Schmidt Calern
  22. GRB980519 optical observations
  23. GRB980519 Optical Observations
  24. GRB980519 Optical Observations
  25. GRB980519 IPN POSITION
  26. GRB980519 Optical Observations
  27. GRB 980519 Optical Observations
  28. GRB980519 optical observations
  29. GRB980515, BeppoSAX IAUC to be submitted
  30. BATSE on-board GRB trigger change
  31. GRB980519, BeppoSAX-WFC updated position
  32. GRB980519, BeppoSAX-WFC position
  33. GRB980515: SAX-WFC updated position
  34. BeppoSAX GRB ALERT: updated position of grb980515
  35. GRB 980425 Radio Light Curve
  36. GRB 980425 Brightness Temperature
  37. BSAX Observations of GRB980425 field
  38. IPN web site of GRBs
  39. GRB980425 BATSE observations
  40. SAX J0840.7+2248 Optical Observations
  41. GRB 980425 optical observations
  42. GRB980425: optical obs.
  43. GRB980425: Radio Observations
  44. GRB 980425 optical observations
  45. report on BSAX observations of GRB980425
  46. GRB 980425 optical observations
  47. GRB 980329 ROSAT observation
  48. GRB980326 X-ray Observations
  49. GRB980326, optical observations
  50. GRB980326, optical observations
  51. GRB980329, Fading IR counterpart to radio source
  52. GRByymmdd, Announcement of automation
  53. GRB980326 IPN annulus
  54. GRB980329
  55. GRB980329 Keck K-band observations
  56. GRB980329 sub-millimeter observations
  57. GRB980329 IPN annulus
  58. GRB980329 optical observations
  59. GRB980329 near-IR observations
  60. GRB980329 near-IR observations
  61. GRB980329 optical observations
  62. GRB980329 infrared observations
  63. GRB980329 optical observations
  64. GRB980326 optical observations
  65. GRB980329 optical observations
  66. GRB980329 VLA observations
  67. GRB980329 near IR observations
  68. GRB980329 optical observations
  69. GRB980329 optical observations
  70. GRB980329 optical observations
  71. GRB980326 optical observations
  72. GRB980326 optical observations
  73. GRB980326 optical observations
  74. GRB980326 optical observations
  75. GRB970508 SAO RAS optical observations
  76. Optical Observations of GRB 970508
  77. GRB 971214: Redshift from Keck Observations
  78. Near-IR follow-up on GRB 971227
  79. GRB971214: Keck R & I-band Observations
  80. GRB 971227: Optical Observations
  81. Optical Observations of the GRB 971227 field
  82. Optical Observations on GRB 971227
  83. GRB971227: Plaskett R-band observations
  84. GRB 971227: Optical clarifications
  85. Optical Observations for GRB 971227
  86. GRB971227: Further CAHA R-band images
  87. GRB971227: LOTIS observations
  88. GRB 971227: CAHA R-band images
  89. GRB 971227: Optical observations
  90. GRB971214: Optical Observations and Calibrations
  91. Sub-millimeter Observations of GRB 971214 at the JCMT
  92. GRB 971214: EUVE Observations
  93. GRB 971214: Redshift from Keck Optical Observations
  94. GRB 971214: Redshift from Keck Optical Observations
  95. GRB 971214: Apache Point Observatory Optical Observations
  96. GRB 971214: KPNO Optical Observations
  97. Optical Observations of GRB 971214 at Keck
  98. GRB 971214: Optical Observations
  99. Radio Observations of GRB 971214 at the VLA
  100. GRB 971214: USNOFS Observations Summary

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