Power companies prepare as solar storms set to hit Earth.
He said solar storms this week could affect communications and global positioning system (GPS) satellites and might even produce an aurora visible as far south as Minnesota and Wisconsin.
The largest solar storm ever recorded was in 1859 when communications infrastructure was limited to telegraphs.
The 1859 solar storm hit telegraph offices around the world and caused a giant aurora visible as far south as the Caribbean Islands.
Some telegraph operators reported electric shocks. Papers caught fire. And many telegraph systems continued to send and receive signals even after operators disconnected batteries, NOAA said on its website.