The northern lights, also known as the aurora borealis, are natural light caused by the solar wind. … [+]
“Interplanetary shocks” that hit Earth’s magnetic field head-on are what scientists need to predict to protect any infrastructure that conducts electricity, according to new research published today in Frontiers in Astronomy and Space Sciences.
The appearance of magnificent displays of green, red, purple and blue glow – like the global geomagnetic storm on May 10 – can signal the arrival on Earth of strong currents that can potentially damage power lines, oil and gas pipelines, railways and submarine cables.
Interplanetary turmoil
An interplanetary shock that can lead to the observation of the beautiful Northern and Southern Lights is a disruption of the solar wind. It is caused by a coronal mass ejection from the sun. A CME is a cloud of magnetic fields and charged particles from the sun that flows into space at speeds of up to 1,900 miles (3,000 kilometers) per second.
The disturbance causes Earth’s protective magnetic bubble to compress, often causing the aurora borealis. However, the impact angle of interplanetary impacts is key to the strength of the currents, the study says.
It’s important because interplanetary shocks are much more common during solar maximum, which scientists believe is happening now.
Geomagnetically induced currents can damage infrastructure that conducts electricity. The more powerful the interplanetary impact, the more powerful the currents and auroras. If scientists can predict that an incoming interplanetary shock will be a head-on rather than a blip, it will help protect infrastructure before impact, the researchers say.
Magnetosphere or magnetic field around the Earth.
Higher peaks
The paper found that shocks that strike the Earth head-on, rather than at an angle, produce the strongest geomagnetically induced currents. Using a database of interplanetary shocks and comparing it to readings of geomagnetically induced currents from a natural gas pipeline in Mäntsälä, Finland – in the “Aurora Zone” – the scientists found that frontal shocks cause higher peaks in geomagnetically induced currents. This is because they compress the magnetic field more.
They also found that the most intense peaks occur around “magnetic midnight,” the time of night (around actual midnight, local time) when the north pole is between the sun and Mäntsälä on Earth’s night side.
Space time
“Auroras and geomagnetically induced currents are caused by similar drivers of space weather,” said Dr. Danny Oliveira of NASA’s Goddard Space Flight Center, the lead author. Space weather is the flow of charged particles from the sun – the solar wind. “The aurora borealis is a visual warning that electrical currents in space can generate these geomagnetically induced currents on earth.”
The appearance of aurora on May 10 was particularly intense. The aurora appears as an oval around the polar regions, but on this date the arrival of several CMEs caused the oval to widen. “The auroral region can significantly expand during severe geomagnetic storms,” Oliveira said. “Normally its southernmost limit is around 70 degrees latitude, but during extreme events it can drop to 40 degrees or even more, which certainly happened during the May 2024 Storm — the worst storm over the past two decades.”
Wishing you clear skies and wide-open eyes.
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