Professor Negreiros on the “Power and Beauty of Geomagnetic Storms”

You may have heard that the Earth recently underwent a very strong geomagnetic storm, the strongest one in about two decades.

Most geomagnetic storms are caused by several eruptions on the sun, known as “coronal mass ejections” (or CME for short). These eruptions are the forceful release of magnetic field lines and solar plasma from the Sun’s outer layer into space. These intense explosions send out a lot of electrons and protons that travel across the solar system at amazing speeds that can be as high as thousands of miles per second! At such high speeds a blast of solar particles from a coronal explosion can arrive at earth in about 10 to 20 hours.

Geomagnetic storms are a stunning and formidable display of the universe’s strength that makes us feel awe and motivates us to keep exploring the mysteries of the cosmos!

When a geomagnetic storm increases the number of particles hitting Earth, Earth’s magnetic field struggles to cope with it! This makes the stunning northern lights more frequent and visible in lower latitudes! However, we also need to be cautious during these events, as these charged particles can damage electric and electronic equipment, especially affecting communication satellites and power grids!

Most of the charged particles that strike Earth are repelled by its magnetic fields, but some of them get caught in the field and follow the field lines. They create the stunning lights of the phenomenon called Aurora Borealis, or Northern Lights, because they are more common at higher latitudes where the earth’s magnetic fields are nearer to the surface, due to the magnetic north pole. 

We are fortunate that our planet has a natural protection: its magnetic field! Earth’s magnetic field works as a shield, blocking most of the high energy charged particles that come from the sun (and from other sources in the universe). During times of high solar activity, like we have seen recently, Earth’s magnetic field had to do more work, because the number and energy of the charged particles from the sun are much higher.