Rare Solar Storm May Make Northern Lights Visible Across US

Stunning Auroras Expected Across US as Solar Storms Merge

A trio of coronal mass ejections (CMEs) that burst forth from the sun’s scorching outer atmosphere on Wednesday are expected to trigger breathtaking auroras across a significant portion of the United States and potentially paint the skies with vibrant hues as far south as Florida this weekend.

Solar Storms’ Journey to Earth

The three CMEs, traveling at a staggering speed of over 1.5 million miles per hour, have coalesced into a single pulse of plasma and magnetic field during their 60-hour voyage from the sun’s atmosphere to our own. Experts at the National Oceanic and Atmospheric Administration’s Space Weather Prediction Center have issued a “severe geomagnetic storm watch” in anticipation of its arrival, marking the first such alert in nearly two decades.

Potential Impact on Auroras and Technology

As a result of this anticipated storm, visible auroras may grace the skies across a wide swath of the United States. An event of this magnitude also has the potential to disrupt radios, satellites, and possibly even some power grids, although most people need not be alarmed.

The Origin: A Massive Sunspot

The genesis of this weekend’s aurora potential lies in a sunspot more than ten times the size of Earth. This sunspot is so enormous that it can be seen with the naked eye through a pair of leftover eclipse glasses, as demonstrated in this tweet. Sunspots are often associated with solar flares and CMEs, and larger, more intense spots can lead to more frequent and powerful releases of matter from the sun’s atmosphere.

Timing and Visibility of Auroras

If the event remains on course, a memorable series of auroras may adorn the night skies over much of the United States during the overnight hours from Friday into early Saturday morning. The event’s timing places the likely peak disruption in the middle of the night across the US, offering a prime viewing opportunity for most of the country.

A geomagnetic storm of this intensity could make the aurora visible overhead from Seattle to Chicago to New York and Washington, DC, with auroras possible as far south as Oklahoma City and Raleigh, North Carolina. Colors may even be visible on the northern horizon as far south as northern Florida. To maximize the chances of seeing any colors in the sky, it is best to escape city lights and cloud cover. The darker and clearer the conditions, the better.

Potential Side Effects and Disruptions

While an aurora is the most visible and eagerly anticipated effect of this solar spectacle, it could also have some unwanted side effects. Scientists rate the intensity of geomagnetic storms on the G-scale, which ranges from G1 (minor) to G5 (extreme). High-end storms are relatively uncommon, with the Space Weather Prediction Center not issuing a G4-level watch since January 2005.

Most geomagnetic storms are relatively weak and only cause auroras and intermittent disruptions for communities at the highest latitudes. Stronger events can produce auroras deep into the southern latitudes and significantly affect power grids and modern technology. However, the potential disruptions this weekend are likely nothing the average person would even notice, much less have to worry about. A G4 geomagnetic storm like the one predicted could hamper long-range radio frequencies and affect satellite communications. The surge of energy into the upper atmosphere could also affect the precision of GPS satellite signals.

The Carrington Event: A Historical Perspective

The strongest geomagnetic storm in modern history was the Carrington Event, the result of an immense CME that reached Earth at the beginning of September 1859. Intense auroras lit up the sky like daylight for much of the US, with northern lights visible all the way into the tropics. The electrical currents induced by magnetic disruptions during the Carrington Event caused power surges throughout telegraph systems, with operators across the US and Europe reporting fires, sparks, and even electrical shocks during the event.

Modern power grids are designed with safety systems to protect equipment in the event of an electrical surge like the one induced by a strong geomagnetic storm. However, if a Carrington-level disruption happened today, it could lead to life-altering and long-lasting blackouts around the globe.