<p>Many examples of ionospheric perturbations observed during large seismic events were recorded by the low-altitude satellite DEMETER. However. there are also ionospheric variations without seismic activity. The present study is devoted to a statistical analysis of the night-time ion density variations. https://www.hindigyanvishv.com/best-flash-CoQ-Clear-100-Ubiquinol-60-Softgels-Citrus-deal-zone/