Auroral wonders: The stunning science and potential hazards

In the past week, there have been particularly strong ejections of matter (so-called CMEs, or coronal mass ejections), which are of the highest class, X. Those directed towards us caused the strongest geomagnetic storm since 2003. Since April 9th, we have been observing exceptionally high auroral activity in the sky.

The Earth's protective system, the magnetic field, reacts in various ways to the stream of solar radiation reaching the Earth. It usually functions efficiently as an insulator, but during a geomagnetic storm, this function can be disrupted. Then the plasma (mainly charged electrons, sometimes protons) previously ejected by the Sun, is directed from space towards the Earth towards its polar regions.

An oval zone forms around the pole, where radiation excites oxygen and nitrogen molecules high above the surface, and they, returning to their natural state, emit multicolored radiation creating the auroras. The red color is due to atomic oxygen and molecular nitrogen excited at about 200,000 meters, green is the glow of molecular oxygen from about 100 to 300,000 meters. There are also blue auroras, as well as pink, when radiation reaches less than about 100,000 meters and excites nitrogen to glow. Some colors, like yellow, are the result of mixing other colors.

The shape of the aurora varies and depends on how radiation breaks through to the atmosphere. Auroras can be spectacular light pillars or waving bands, but they can also be ordinary glows. The stronger the geomagnetic storm, the more southward the area where the aurora is visible to the naked eye extends. Auroras can even reach the equator, but these are very rare cases known only from historical records.

Humans are constructed so that the beauty of natural processes, such as the auroras, makes them wonder if there is a hidden danger in this charm.

The aurora itself has no impact on the functioning of our civilization because it is merely a beautiful light phenomenon. However, the radiation causing it, which Earth's magnetic field does not effectively block, can cause real damage. However, these are primarily large-scale problems, especially for devices high above the Earth's surface. At the same time, it should be noted that the impact of a geomagnetic storm concerns those aspects of human civilization that are related to electricity.

Therefore, during increased solar activity, there can be, for example, satellite failures in orbit, disruptions in the Earth's power network and communications, and even increased wear of structures such as pipelines. The consequences also affect radio transmissions (including GPS systems).

Regarding the strength of the geomagnetic storm, we do not have to worry about the direct negative impact of the aurora borealis on the body's function, as is the case with pigeons relying on biological compasses. The energetic radiation that still reaches Earth, even if it affects the operation of devices such as pacemakers, will not disrupt their function in a way that is dangerous to health. More damage may be caused by indirect effects, disruptions of navigation, and cell phone communications.

The impact on our well-being is a matter of more individual subconscious reactions, but even here, there is no direct correlation. However, science does not fully rule out a connection between episodes of auroral occurrences and what happens in humans in the nervous and circulatory systems. However, this would be related to a radiation dose significantly smaller than we receive, for example, during an X-ray examination and even more invasive procedures like CT scans. Astronauts in space face real danger from geomagnetic storms, hence there are warning systems to enable them to hide in well-insulated rooms. Usually, these are vehicles in which humans travel into space.