Brian McDonald
A strong G4 geomagnetic storm could emerge on Friday, triggering surveillance of a storm of this magnitude by NOAA officials for the first time in nearly 20 years. The clock comes after days of solar activity that apparently sent multiple bursts of plasma and magnetic fields toward Earth.
G4 are the second strongest form of geomagnetic storms and are known to cause widespread voltage control problems. According to NOAA, they can also cause some protection systems to “exclude important assets from the network,” as well as spacecraft guidance problems. Northern Lights, also known as the Aurora Borealis, can be seen as far south as Alabama and as far north as California.
On a Press release on Thursday, NOAA said the most recent series of solar events began on May 8, when a large sunspot cluster produced “several moderate to strong solar flares.” Solar flares are radiation blasts known to be the largest explosive events in the solar system, according to NASA. The area where the recent flares occurred is 16 times the diameter of Earth, NOAA said, and more solar activity is expected.
There have also been a series of coronal mass ejections (CMEs), which are explosions of plasma and magnetic fields coming out of the solar corona, the outermost part of the solar atmosphere. At least five CMEs appear to be headed toward Earth and could arrive as early as midday Friday and persist through Sunday, the agency said.
“This is an unusual event,” NOAA said.
NOAA
“Geomagnetic storms can impact infrastructure in near-Earth orbit and at the Earth’s surface, potentially disrupting communications, the electrical power grid, navigation, radio and satellite operations,” NOAA said. “[The Space Weather Prediction Center] notified the operators of these systems so they can take protective measures.”
NOAA said this is the first time a storm warning was issued for a G4 since January 2005. There is an average of 100 severe geomagnetic storms in each solar cycle, but so far, only three have been observed in the most recent cycle that began in December 2019. The most recent occurred on March 23. The last time there was a G5 or extreme geomagnetic storm was in October 2003, when it caused power outages in Sweden and damaged transformers in South Africa.
Li Cohen
