The strongest activity of the Sun in the last 11 years is expected! The consequences could be dire

Recently, many more people around the world have been able to see the northern and southern lights with the naked eye than usual.
This unusual experience was caused by a powerful solar storm that affected the Earth’s magnetic field. The Sun has reached its peak activity in its 11-year cycle, which means we can expect more explosive bursts of particles.

Under normal conditions, this creates beautiful auras in the sky and geomagnetic storms that can damage infrastructure such as power grids and orbiting satellites. What actually happens to cause these phenomena? The northern and southern lights are usually only visible at very high and very low latitudes.

High-energy particles from the Sun come toward Earth guided by the Sun’s magnetic field. They are transferred into the Earth’s magnetic field in a process known as reconnection, Science Alert reports.

Why did the Aurora Borealis come about?

These very fast and hot particles then travel along Earth’s magnetic field lines – the path through which the magnetic force works – until they hit neutral, cool atmospheric particles like oxygen, hydrogen or nitrogen. At this moment, part of the energy is lost – by heating the local environment.

Atmospheric particles do not want to be too energetic, so they release some of that energy in the form of visible light. Depending on which element is overheated, you will see different sets of wavelengths – and colors – emitted in the visible light range of the electromagnetic spectrum.

This is the source of the aurora borealis that we can see at high latitudes, and during strong solar events at lower latitudes. The blue and purple colors in the aura come from nitrogen, while the green and red come from oxygen. This process happens continuously, but due to the shape of the Earth’s magnetic field, the area fed by the incoming particles is located at very high and low latitudes (the Arctic or Antarctica in general).

What happened to allow us to see the aurora borealis much further south in the Northern Hemisphere?

You may remember in school placing iron filings over magnets to see how they align with the magnetic field. You can repeat that experiment multiple times and see the same shape each time. Earth’s magnetic field is also constant, but it can compress and release depending on the strength of the Sun. Simply put, imagine two half-inflated balloons pressed together.

When you inflate a balloon, by adding more gas to it, the pressure will increase and push the smaller balloon back. When you release that extra gas, the smaller balloon relaxes and pushes back. The stronger the pressure, the closer to the equator the relevant magnetic field lines are pushed, meaning that auroras can be seen.

This is where the potential problems arise: a moving magnetic field can generate current in anything that conducts electricity.

Transmission lines the most vulnerable

For modern infrastructure, the largest currents are generated in power lines, railways and underground pipelines. The speed of this movement is also important and is monitored by measuring how much the magnetic field is perturbed from “normal”. One such measure used by researchers is called the Storm Disturbance Index.

By this measure, the geomagnetic storms of May 10 and 11 were extremely strong. With such a strong storm there is a potential danger of electrocution. Power lines are most at risk, but they benefit from the protection built into power plants. They have been in focus since the 1989 geomagnetic storm.