The UV pulse partially ionized Earth's upper atmosphere, disturbing the normal propagation of radio signals around the planet. Monitoring stations in Norway and Ireland recorded the sudden ionospheric disturbance. Finally, solar protons accelerated by the blast are swarming around Earth. The radiation storm, in progress, ranks "S1" on NOAA space weather scales, which means it poses no serious threat to satellites or astronauts. This could change if the storm continues to intensify.