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A series of solar flares and coronal mass ejections from the sun have the potential to create dazzling auroras that can be seen as far south as Alabama and northern California, but also disrupt communications on Earth tonight and into the weekend, according to National Oceanic and Atmospheric Administration’s Space Weather Prediction Center.
The center, which is a division of the National Weather Service, has issued a severe geomagnetic storm watch for Friday evening. It is the first such watch to be released since January 2005.
As of Friday afternoon, scientists at the center were observing a major disturbance in Earth’s magnetic field known as a G4, or strong geomagnetic storm. This is a severity level 4 out of 5.
Conditions indicative of a strong geomagnetic storm were first observed by the Space Weather Prediction Center at 12:37 a.m. ET, after traveling from the sun and reaching satellites that monitor space weather 1 million miles (1.6 million kilometers ) from the ground.
As the sun approaches peak activity in its 11-year cycle, known as solar maximum, later this year, researchers have observed increasingly intense solar flares erupting from the fireball.
Increased solar activity causes auroras that dance around Earth’s poles, known as the northern lights, or aurora borealis, and the southern lights, or australis. When energized particles from a coronal mass ejection reach Earth’s magnetic field, they interact with gases in the atmosphere to create different colored light in the sky.
The Space Weather Prediction Center has tracked multiple powerful flares emanating from a large sunspot cluster on the sun’s surface since Wednesday. The cluster is 16 times the diameter of Earth.
Scientists also observed at least seven coronal mass ejections, or large clouds of ionized gas called plasma and magnetic fields, erupting from the sun’s outer atmosphere, breaking free from the sun toward Earth. These significant outbursts are expected to continue through Sunday.
NASA/SDO
NASA’s Solar Dynamics Observatory captured this image of a solar flare in extreme ultraviolet light on May 2. The flare is the bright flash to the upper middle zone of the sun.
The center’s space weather scale covers three categories: solar flares that cause radio frequency disruptions, geomagnetic storms, and solar radiation storms.
Current solar activity is capable of producing a solar radiation storm, according to Sean Dahl, service coordinator for the Space Weather Prediction Center.
“This is the lowest end of our scale,” Dahl said. “It does mean things for some missile launch operations and satellite operators. But at this point it’s nothing that can’t be handled as far as we understand it. The potential for stronger events is certainly there and we will see if it materializes.”
The peak of geomagnetic storm activity for Earth could occur between 2 a.m. and 5 a.m. ET on Saturday, the center predicted.
The center described this as an “unusual event”. There have been three geomagnetic storms since December 2019, but all were considered weak, according to the center.
Geomagnetic storms triggered by the sun in recent months have led to visible auroras in places where they are rarely seen, including as far south as New Mexico, Missouri, North Carolina and California in the United States and southeast England and other parts of the United Kingdom .
The solar storm caused a dazzling aurora to light up the sky over New Zealand around 6:20am local time.
Courtesy of Andrew Dixon
Andrew Dixon captured an image of the aurora over Central Otago, New Zealand’s South Island, using his iPhone 13 plus with a three-second exposure.
Depending on the location, the auroras may not always be visible from above, but keep an eye on the horizon, experts say, because they can create a colorful image there, too.
Even if the auroras aren’t visible in the sky, experts at the center recommend taking pictures of the sky with your phone because the images can capture what you can’t see with the naked eye.
“A strong storm would mean the aurora would likely be visible in southern Michigan,” Michael Limon, a professor of climate and space science and engineering at the University of Michigan in Ann Arbor, said in a statement. “Get away from the city lights to a place with clear skies and you should be able to see the green or red glow of the aurora in the sky.”
Courtesy of Andrew Dixon
Dixon lives in a rural area with “virtually no light pollution,” he told CNN.
When coronal mass ejections are directed toward Earth, they can cause geomagnetic storms, or large disturbances in Earth’s magnetic field.
“Geomagnetic storms can affect infrastructure in Earth orbit and on Earth’s surface, potentially disrupting communications, power grids, navigation, radio and satellite operations,” according to the Space Weather Prediction Center. “(The center) has notified the operators of these systems so they can take protective action.”
The Center has notified operators in these areas to take action to mitigate the potential for any impacts, which include the possibility of increased and more frequent voltage control problems. Other aspects that operators will monitor include the likelihood of anomalies or impacts on satellite operations and frequent or longer periods of GPS degradation.
In turn, operators also make sure power lines are working as expected, ensure alternate equipment is available and functioning and any maintenance is down, Dahl said.
“But the key element here is that they know what’s causing something if the situation develops, which will allow us to be able to take the right steps to mitigate and control any issues that develop,” Dahl said.
When coronal mass ejections arrive, they bring their own magnetic field that can overcome power lines and trigger electrical currents, so operators will be watching for any signs of such activity, said Rob Steinberg, a space scientist at the Center for Space Weather Prediction.
“When we talk about impacts on the power grid, we’re talking about high-voltage transmission lines. That’s where these currents can develop. There is no line whatsoever running from a small transformer to their home,” Dahl said. “It really only develops on the high-voltage transmission lines, which creates problems for the main transformers that control the distribution.”
Solar storms generated by the sun can also cause radio outages and even pose a risk to manned space missions.
NASA’s Space Radiation Analysis Group is dedicated to monitoring conditions for astronauts aboard the International Space Station. If there appears to be an increased risk of radiation, astronauts can move to parts of the station that are better shielded.
The center warned that additional solar activity could cause geomagnetic storm conditions to continue through the weekend.
So far, researchers have observed only three severe geomagnetic storms during the current solar cycle, which began in December 2019, according to the center.
A G5 or extreme geomagnetic storm occurred before that in October 2003, causing blackouts in Sweden and damaged power transformers in South Africa, according to the center.
Experts at the center say they are “a little concerned,” but mainly because such events are rare.
The team likened it to preparing for a summer storm: Keep batteries and a weather radio handy in case of a power outage, but said people shouldn’t “do anything unusual” to prepare for space weather. No disruption to internet or mobile services is expected. And any GPS outage is not expected to be prolonged, as long as providers can quickly re-lock to satellite signals, according to experts at the center.
Every 11 years or so, the sun experiences periods of low and high solar activity, which is related to the amount of sunspots on its surface. The sun’s strong and ever-changing magnetic fields govern these dark regions, some of which can be Earth-sized or larger.
In the course of the solar cycle, the sun will go from a calm to an intense and active period. During the peak of activity, called solar maximum, the sun’s magnetic poles reverse. The sun will then set again during solar minimum.
The solar maximum is expected to peak in mid-to-late 2024, but the sun will remain active for several years after that.
Teams at the Center for Space Weather Prediction use data from ground-based and space-based observatories, magnetic maps of the solar surface, and ultraviolet observations of the sun’s outer atmosphere to determine when the sun is most likely to send solar flares, coronal mass ejections, and more space weather that can affect Earth.
Solar flares can affect communications and GPS almost immediately because they disrupt Earth’s ionosphere or part of the upper atmosphere.
Energetic particles released from the sun can also disrupt spacecraft electronics and affect astronauts without proper protection within 20 minutes to several hours.
Material sent flying away from the sun during a coronal mass ejection can arrive at Earth between 30 and 72 hours later, causing geomagnetic storms that affect satellites and create electrical currents in the upper atmosphere that pass through the ground and can have an impact on the electrical energy grids.
The storms also affect the flight patterns of commercial airlines, which are instructed to stay away from Earth’s poles during geomagnetic storms due to loss of communications or navigational capabilities.
Extreme storms have happened before, such as the one that knocked out the Quebec power grid in 1989 and the Carrington event of 1859. The latter remains the most intense geomagnetic storm ever recorded, causing sparks and fires at telegraph stations.
If such an event were to occur today, it could cause trillions of dollars worth of damage and cause some power grids to fail for a significant period of time.
Correction: A previous version of this story misstated the date of an earlier G5 storm.
