gcn.nasa.gov (effective April 17, 2023)

The modernized GCN Circulars experience is part of the new GCN web site, where you can:

Browse and search Circulars in our all-new archive.
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Submit Circulars with our new Web form, or continue to submit by email.

This legacy GCN Classic Circulars service has been disabled.

All legacy accounts are transferred to the new system.
The legacy archive is frozen.
Email submissions to the old address will be forwarded to the new system and processed normally. We encourage use of the new submission address.

For questions, please contact the GCN Team.

Burst-n-Transient Information (Current and Archives)

CIRCULARS (current)

Circulars grouped by GRB/transient (updated in real-time)

Links to pages that hall athe circulars for a iven event on a single page.

Circulars (updated in real-time)

A sequential archive in serial number order of all GCN Circulars.

Reports (Active: 2006-2014, no longer supported: >2014)

A sequential archive in serial number order of all GCN Reports.

NOTICES (active missions; semi sorted with newest at top down to the oldest at the bottom)

LIGO/Virgo Notices (updated in real-time)

This table contains the GCN/LVC Notices.

ICECUBE_ASTROTRACK_GOLD/_BRONZE Notices (updated in real-time) and

HAWC_BURST_MONITOR Notices (updated in real-time)

AMON_NU_EM_COINC Notices (updated in real-time)

AMON_CASCADE Notices (updated in real-time)

These tables contain the GCN/AMON_ICECUBE GOLD/BRONZE, HAWC BURST, AMON_NU_EM_COINC, and CASCADE neutrino event Notices.

GECAM GRB Information (updated in real-time)

These tables contain the results of the real-time processing and the off-line ground processing of the GECAM triggers (bursts and non-bursts).

CALET Lightcurves of tranients (updated in real-time)

This table contains lightcurve information from detections by CALET-GBM.

MAXI GRB/Unknown/Known Information (updated in real-time)

This table contains information about detections by MAXI (GRBs and other Unknowun sources, and previously Known sources).

Fermi GRB Information (updated in real-time) and

LAT Monitor and Transient Information (notices updated in real-time, but the analysis takes 1-7 days)

These tables contain information about GRBs, flares from known sources, and new sources detected by Fermi.

Swift GRB Information (updated in real-time, 10-200 sec) and Ground-processed (1-6 hrs delay)

These tables contain the results of the real-time processing and the off-line ground processing of the Swift triggers (bursts and non-bursts).

Swift-BAT SubSub_Threshold and Known_Source Trigger Information (updated once per 18-30 hrs)

This page contains two tables of daily compliations of the BAT SubSubThreshold triggers and the Known-Source detections.

Swift-BAT Monitor Information (updated in near real-time, 1-6 hrs)

This table contains the results of the near-real-time automated processing of the Swift-BAT All-Sky Monitor program.

INTEGRAL GRB Positions (updated in real-time) and SPI-ACS Triggers, Lightcurves (updated in real-time)

These tables contains information about GRBs/Transients/noise detected by INTEGRAL.

AGILE GRB Information (updated in real-time) and AGILE MCAL Information (updated in real-time)

This table contains information about GRBs detected by the SuperAGILE instrument, and detections and lightcurves by the MCAL instrument on the AGILE spacecraft.

Counterpart (updated in real-time)

This table contains the GCN/COUNTERPART notices submitted by follow-up observers on detections of counterparts to GRBs.

IPN_Raw Notices (updated in real-time) and IPN_Position Notices (discontinued 2003) and IPN_Segment Notices (archive)

These tables contain the GCN/IPN Position, Segment , and Lightcurve Notices.

Wind-KONUS Notices (updated in real-time)

This table contains the GCN/KONUS Notices (light curves from 1994 to current).

MOA Notices (updated in real-time)

This table contains the GCN/MOA gravitational lensing event Notices.

SNEWS Notices (updated in real-time)

This table contains the GCN/SNEWS neutrino event Notices.

SK_SN Notices (updated in real-time)

This table contains the GCN/SK_SN neutrino event Notices.

NOTICES (discontinued missions or notice types)

AMON_ICECUBE_HESE Notices and EHE Notices

This table contains the GCN/AMON_ICECUBE HESE and EHE neutrino event Notices (archive: Mmm YYYY to Mmm YYYY).

Suzaku Notices (archive: Jan 2013 - May 2015)

This table contains the GCN/SUZAKU Lightcurve Notices.

RXTE GRB Information (archive)

This table contains information about observations (or attempted observations) by RXTE (PCA and ASM) on GRBs.

HETE GRB Information (archive)

This table contains information about observations by HETE (WMM and SXC) on GRBs (Feb 2001 to Aug 2006).

MILAGRO Notices (archive)

This table contains the GCN/MILAGRO Notices on transients (Nov 2005 to May 2008).

BeppoSAX GRB Information (archive)

This table contains information about observations by SAX (WFC and NFI) on GRBs (Dec 1998 to Apr 2002).

NEAR-XGRS Notices (archive)

This table contains the GCN/NEAR Light curves (Feb 1999 to Feb 2001).

ALEXIS extreme-UV Transient Information (archive)

This table contains information about detection by ALEXIS in the extreme-UV bandpass (1995-1999).

BATSE Triggers Information (archive)

This table contains information about each BATSE trigger (locations, peak intensities, fluences, light curves, etc).

COMPTEL GRB Information (archive)

This table contains information about GRBs detected (and not detected) by CGRO-COMPTEL (Nov 1997 to May 2000).

GRO SSC Status Reports (archive)

These reports contain the current status of the Compton-GRO spacecraft and the individual instruments, any changes made to the observing program (because of ToO's, etc), and timely information about the C-GRO program (GI proposal information, etc). They are issued by the CGRO - Science Support Center.