The Northern Lights, also known as the aurora, are a natural light display caused by the solar wind. … [+]
“Interplanetary shocks” that strike Earth’s magnetic field are what scientists need to anticipate in order to protect any infrastructure that conducts electricity, according to a new study published today in Frontiers in Astronomy and Space Sciences.
The appearance of spectacular displays of green, red, purple and blue aurora — such as the global geomagnetic storm on May 10 — could signal the arrival of strong currents on Earth that could potentially damage power transmission lines, oil pipelines and gas, railways and submarine cables.
Interplanetary strike
An interplanetary strike – which can lead to seeing the beautiful Northern Lights and Southern Lights – is a disruption in the solar wind. It is caused by coronal mass ejections from the sun. A CME is a cloud of magnetic fields and charged particles from the sun streaming through space at up to 1,900 miles (3,000 kilometers) per second.
The disturbance causes Earth’s protective magnetic bubble to contract, often causing the aurora. However, it is the impact angle of interplanetary shocks that is key to the strength of the jets, the research says.
It’s important because interplanetary collisions are much more common during solar maximum, which scientists think is happening now.
Geomagnetically induced currents can damage infrastructure that conducts electricity. The more powerful an interplanetary shock, the more powerful the currents and auroras. If scientists can predict that an incoming interplanetary strike will be head-on, rather than a sighting strike, it will help protect infrastructure before impact, researchers say.
The magnetosphere or magnetic field around the Earth.
High Peaks
The paper found that shocks that hit Earth head-on, rather than at an angle, trigger the strongest geomagnetically induced currents. Using a database of interplanetary shocks and cross-referencing it with readings of geomagnetically induced currents from a natural gas pipeline in Mäntsälä, Finland—in the “aurora zone”—scientists found that frontal shocks cause higher peaks in the currents induced geomagnetic. This is because they compress the magnetic field more.
They also found that the most intense peaks occurred around “magnetic midnight,” the time of night (around current midnight, local time) when the north pole was between the sun and Mäntsälä on Earth’s night side.
Space weather
“Auroras and geomagnetically induced currents are caused by similar drivers of space weather,” said Dr. Denny Oliveira of NASA’s Goddard Space Flight Center, lead author. Space weather is the flow of charged particles from the sun – the solar wind. “The aurora is a visual warning that electric currents in space can generate these induced geomagnetic currents on Earth.”
The aurora display on May 10 was particularly intense. The aurora appears as an oval around the polar regions, but on that date, the arrival of several CMEs caused the oval to widen. “The auroral region can expand greatly during strong geomagnetic storms,” Oliveira said. “Usually, its southernmost limit is around latitudes of 70 degrees, but during extreme events, it can drop to 40 degrees or even further, which certainly happened during the May 2024 storm – the strongest storm in two the last decades.
I wish you clear skies and open eyes.
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