Tonight’s Historic Geomagnetic Storm: Look Out for Aurorae

A rare severe geomagnetic storm hitting Earth could allow viewers as far south as Alabama to witness aurora tonight.

An image of an aurora captured in Norway in 2019. Credit: Matt Houghton on Unsplash.

On May 9th, 2024, the National Oceanic and Atmospheric Administration’s Space and Weather Center announced a Level 4 (severe) geomagnetic storm watch. The watch was upgraded from a Level 3 (moderate) after several solar flares combined on their way to Earth.

This is the first time since 2005 that the agency has put out a severe geomagnetic storm watch, as these types of events are extremely rare.

The upcoming geomagnetic storm began as two large sunspots merging, sending out at least two X-class and several M-class solar flares. The new sunspot now has a diameter 16 times that of Earth’s. This all culminated in several coronal mass ejections (CMEs), which are expected to merge and hit Earth late tonight or early tomorrow.

Sunspots on the surface of the Sun. Credit: NASA.

Solar storms are typically caught in the Earth’s magnetosphere, a layer of the upper atmosphere that protects us from dangerous radiation. The charged particles from CMEs headed towards Earth…