A severe solar storm is headed to Earth that could stress power grids even more as the U.S. deals with major back-to-back hurricanes, space weather forecasters said Wednesday.

The same solar region that brought an outburst of night-time beauty in early May is coming back around. But things have changed, a space weather expert tells NPR.

The solar storm that's pushing sightings of the Northern Lights to lower latitudes is forecast to continue into the coming days, but its impact has likely peaked.

The National Oceanic and Atmospheric Administration says there have been measurable effects and impacts from the biggest geomagnetic storm in decades.

We are at the height of the Sun's activity in its eleven year cycle, known to astronomers as the solar maximum. This means that over the next several months there's going to be a lot of solar activity. It's got us thinking back to 1859. That's when astronomer Richard Carrington was studying the Sun when he witnessed the most intense geomagnetic storm recorded in history. The storm, triggered by a giant solar flare, sent brilliant auroral displays across the globe causing electrical sparking and fires in telegraph stations. This encore episode, Regina talks to solar physicist Dr. Samaiyah Farid about what's now known as the Carrington event and about what may happen the next time a massive solar storm hits Earth.

Want to hear us cover other parts of the solar system? Email the show at shortwave@npr.org to let us know!

The dark patches, known as coronal holes, are regions where solar wind escapes more quickly and readily into space. Geomagnetic storms can disrupt GPS and hurt the power grid.