(NEXSTAR) – Coronal mass ejections — or explosive accelerations of plasma and magnetic material from the Sun — can be strong enough to disturb the Earth’s magnetosphere, producing geomagnetic storms powerful enough to cause both the northern lights and widespread telecommunications disruptions.
Could a CME actually wipe out life on Earth, though?
No, it can’t, according to experts. But a strong storm could still have devastating consequences.
Coronal mass ejections, or CMEs for short, are observed around once per week during a solar minimum (the sun’s less-active phase) and up to several times per day during a solar maximum. But rarely does a CME event affect the day-to-day operations of Earth’s inhabitants. It’s also “not considered possible” that a CME would destroy life on our planet, a space weather forecaster told Nexstar.
“Earth is very well protected by our atmosphere and our protective magnetic barrier,” Shawn Dahl, a forecaster with the National Oceanic and Atmospheric Administration’s Space Weather Prediction Center (SWPC), said.
That doesn’t mean CMEs can’t be disruptive or extremely detrimental to our infrastructure, though.
A solar flare observed in 1859 is thought to have fueled a CME that produced the Carrington Event, a geomagnetic storm regarded as the most intense in recorded history. Impacts included outages to telegraph services worldwide, with telegraph lines sparking and, in some cases, causing shocks to the telegraph operators and fires at their stations.
There were also dazzling auroras observed in both the northern and southern hemispheres, illuminating the sky enough to allow viewers to read newspapers, according to recounts compiled by NASA. But they also caused awe and distress.
“Many took it to be a sign of some great disaster or important event, citing numerous instances when such warnings have been given,” the New Orleans Daily Picayune wrote at the time, NASA noted.
Electrical and telecommunications companies today are working to install systems to mitigate the effects of a similar geomagnetic storm. But still, such an event could have serious consequences, especially since there are more technological systems at risk than in 1859.
“If the Carrington Event happened today, it would have even more severe impacts, such as widespread electrical disruptions, persistent blackouts, and interruptions to global communications,” Vanessa Thomas, a science writer for NASA, wrote in 2023. “Such technological chaos could cripple economies and endanger the safety and livelihoods of people worldwide.”
Only a few storms even approaching the level of the Carrington Event have been observed in the years since, including one that knocked out power to the entire Canadian province of Quebec in 1989, and another series of storms in 2003 that knocked out some satellites, GPS and airline radio communications systems.
But the Earth also dodged a celestial bullet in July 2012, when a CME at least as powerful as the one that caused the Carrington Event accelerated into our planet’s orbit, but narrowly missing the Earth.
“If it had hit, we would still be picking up the pieces,” said Daniel Baker, a space researcher and distinguished professor at the University of Colorado, in a 2014 article. Baker, together with NASA scientists, theorized that the event would have caused widespread blackouts, damage to major transformer systems, and trillions in damage. NASA even wrote that it could have “knock[ed] modern civilization back to the 18th century.”
Thankfully, the odds of a CME causing a storm of that magnitude are relatively low. Data on previous CME events (using evidence found in arctic ice) indicates that such a storm occurs once every 500 years or so. And in a 2021 study by UC Irvine researcher Sangeetha Abdu Jyoth, the author cited astrophysicists who estimated the likelihood of even an internet-disrupting event at between 1.6% and 12% per decade.
Even still, human life is in no direct danger from an especially powerful CME striking Earth.
“The most intense storms can disrupt technology (like satellites in space, or power grids on Earth), threaten the health of astronauts in space, or even increase radiation exposure for high-altitude aircraft near the poles,” a NASA scientist told Nexstar in an emailed statement. “However, people on the surface of the Earth are not in danger from the effects of solar storms.”