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GCN Circular 32745

GRB221009A: Ionospheric disturbance observed in India
2022-10-13T21:48:26Z (2 years ago)
Doug Welch at McMaster University <>
Authors: A. Guha (Centre for Lightning and Thunderstorm Studies (CeLTS), 
Department of Physics, Tripura University, India.), P. Nicholson 
(Todmorden, UK)

We report the observation of a sudden disturbance of radio propagation 
in the very low frequency (VLF) band between 18kHz and 23kHz coincident with
GRB221009A. Affected were phase and amplitude of MSK ("Minimum Shift 
Keying") signals from naval transmitters monitored by the Indian 
Lightning Detection Network.

The GRB221009A exceeded 70 degrees elevation at all receiver sites.

The Indian Lightning Detection Network (ILDN) is an experimental network 
of 10 VLF receivers operated by collaborating institutions for lightning 
location and observation of other VLF phenomena on the Indian subcontinent.
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